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/*!
\page designer-manual.html
\title Qt Designer Manual
\ingroup qttools
\keyword Qt Designer
\QD is Qt's tool for designing and building graphical user
interfaces (GUIs) from Qt components. You can compose and customize your
widgets or dialogs in a what-you-see-is-what-you-get (WYSIWYG) manner, and
test them using different styles and resolutions.
Widgets and forms created with \QD integrated seamlessly with programmed
code, using Qt's signals and slots mechanism, that lets you easily assign
behavior to graphical elements. All properties set in \QD can be changed
dynamically within the code. Furthermore, features like widget promotion
and custom plugins allow you to use your own components with \QD.
If you are new to \QD, you can take a look at the
\l{Getting To Know Qt Designer} document. For a quick tutorial on how to
use \QD, refer to \l{A Quick Start to Qt Designer}.
\image designer-multiple-screenshot.png
For more information on using \QD, you can take a look at the following
links:
\list
\o \l{Qt Designer's Editing Modes}
\list
\o \l{Qt Designer's Widget Editing Mode}{Widget Editing Mode}
\o \l{Qt Designer's Signals and Slots Editing Mode}
{Signals and Slots Editing Mode}
\o \l{Qt Designer's Buddy Editing Mode}
{Buddy Editing Mode}
\o \l{Qt Designer's Tab Order Editing Mode}
{Tab Order Editing Mode}
\endlist
\o \l{Using Layouts in Qt Designer}
\o \l{Saving, Previewing and Printing Forms in Qt Designer}
\o \l{Using Containers in Qt Designer}
\o \l{Creating Main Windows in Qt Designer}
\o \l{Editing Resources with Qt Designer}
\o \l{Using Stylesheets with Qt Designer}
\o \l{Using a Designer UI File in Your Application}
\endlist
For advanced usage of \QD, you can refer to these links:
\list
\o \l{Customizing Qt Designer Forms}
\o \l{Using Custom Widgets with Qt Designer}
\o \l{Creating Custom Widgets for Qt Designer}
\o \l{Creating Custom Widget Extensions}
\o \l{Qt Designer's UI File Format}
\endlist
\section1 Legal Notices
Some source code in \QD is licensed under specific highly permissive
licenses from the original authors. The Qt team gratefully acknowledges
these contributions to \QD and all uses of \QD should also acknowledge
these contributions and quote the following license statements in an
appendix to the documentation.
\list
\i \l{Implementation of the Recursive Shadow Casting Algorithm in Qt Designer}
\endlist
*/
/*!
\page designer-to-know.html
\contentspage {Qt Designer Manual}{Contents}
\title Getting to Know Qt Designer
\tableofcontents
\image designer-screenshot.png
\section1 Launching Designer
The way that you launch \QD depends on your platform:
\list
\i On Windows, click the Start button, under the \gui Programs submenu,
open the \gui{Qt 4} submenu and click \gui Designer.
\i On Unix or Linux, you might find a \QD icon on the desktop
background or in the desktop start menu under the \gui Programming
or \gui Development submenus. You can launch \QD from this icon.
Alternatively, you can type \c{designer} in a terminal window.
\i On Mac OS X, double click on \QD in \gui Finder.
\endlist
\section1 The User Interface
When used as a standalone application, \QD's user interface can be
configured to provide either a multi-window user interface (the default
mode), or it can be used in docked window mode. When used from within an
integrated development environment (IDE) only the multi-window user
interface is available. You can switch modes in the \gui Preferences dialog
from the \gui Edit menu.
In multi-window mode, you can arrange each of the tool windows to suit your
working style. The main window consists of a menu bar, a tool bar, and a
widget box that contains the widgets you can use to create your user
interface.
\target MainWindow
\table
\row
\i \inlineimage designer-main-window.png
\i \bold{Qt Designer's Main Window}
The menu bar provides all the standard actions for managing forms,
using the clipboard, and accessing application-specific help.
The current editing mode, the tool windows, and the forms in use can
also be accessed via the menu bar.
The tool bar displays common actions that are used when editing a form.
These are also available via the main menu.
The widget box provides common widgets and layouts that are used to
design components. These are grouped into categories that reflect their
uses or features.
\endtable
Most features of \QD are accessible via the menu bar, the tool bar, or the
widget box. Some features are also available through context menus that can
be opened over the form windows. On most platforms, the right mouse is used
to open context menus.
\target WidgetBox
\table
\row
\i \inlineimage designer-widget-box.png
\i \bold{Qt Designer's Widget Box}
The widget box provides a selection of standard Qt widgets, layouts,
and other objects that can be used to create user interfaces on forms.
Each of the categories in the widget box contain widgets with similar
uses or related features.
\note Since Qt 4.4, new widgets have been included, e.g.,
QPlainTextEdit, QCommandLinkButton, QScrollArea, QMdiArea, and
QWebView.
You can display all of the available objects in a category by clicking
on the handle next to the category label. When in
\l{Qt Designer's Widget Editing Mode}{Widget Editing
Mode}, you can add objects to a form by dragging the appropriate items
from the widget box onto the form, and dropping them in the required
locations.
\QD provides a scratch pad feature that allows you to collect
frequently used objects in a separate category. The scratch pad
category can be filled with any widget currently displayed in a form
by dragging them from the form and dropping them onto the widget box.
These widgets can be used in the same way as any other widgets, but
they can also contain child widgets. Open a context menu over a widget
to change its name or remove it from the scratch pad.
\endtable
\section1 The Concept of Layouts in Qt
A layout is used to arrange and manage the elements that make up a user
interface. Qt provides a number of classes to automatically handle layouts
-- QHBoxLayout, QVBoxLayout, QGridLayout, and QFormLayout. These classes
solve the challenge of laying out widgets automatically, providing a user
interface that behaves predictably. Fortunately knowledge of the layout
classes is not required to arrange widgets with \QD. Instead, select one of
the \gui{Lay Out Horizontally}, \gui{Lay Out in a Grid}, etc., options from
the context menu.
Each Qt widget has a recommended size, known as \l{QWidget::}{sizeHint()}.
The layout manager will attempt to resize a widget to meet its size hint.
In some cases, there is no need to have a different size. For example, the
height of a QLineEdit is always a fixed value, depending on font size and
style. In other cases, you may require the size to change, e.g., the width
of a QLineEdit or the width and height of item view widgets. This is where
the widget size constraints -- \l{QWidget::minimumSize()}{minimumSize} and
\l{QWidget::maximumSize()}{maximumSize} constraints come into play. These
are properties you can set in the property editor. For example, to override
the default \l{QWidget::}{sizeHint()}, simply set
\l{QWidget::minimumSize()}{minimumSize} and \l{QWidget::maximumSize()}
{maximumSize} to the same value. Alternatively, to use the current size as
a size constraint value, choose one of the \gui{Size Constraint} options
from the widget's context menu. The layout will then ensure that those
constraints are met. To control the size of your widgets via code, you can
reimplement \l{QWidget::}{sizeHint()} in your code.
The screenshot below shows the breakdown of a basic user interface designed
using a grid. The coordinates on the screenshot show the position of each
widget within the grid.
\image addressbook-tutorial-part3-labeled-layout.png
\note Inside the grid, the QPushButton objects are actually nested. The
buttons on the right are first placed in a QVBoxLayout; the buttons at the
bottom are first placed in a QHBoxLayout. Finally, they are put into
coordinates (1,2) and (3,1) of the QGridLayout.
To visualize, imagine the layout as a box that shrinks as much as possible,
attempting to \e squeeze your widgets in a neat arrangement, and, at the
same time, maximize the use of available space.
Qt's layouts help when you:
\list 1
\i Resize the user face to fit different window sizes.
\i Resize elements within the user interface to suit different
localizations.
\i Arrange elements to adhere to layout guidelines for different
platforms.
\endlist
So, you no longer have to worry about rearranging widgets for different
platforms, settings, and languages.
The example below shows how different localizations can affect the user
interface. When a localization requires more space for longer text strings
the Qt layout automatically scales to accommodate this, while ensuring that
the user interface looks presentable and still matches the platform
guidelines.
\table
\header
\i A Dialog in English
\i A Dialog in French
\row
\i \image designer-english-dialog.png
\i \image designer-french-dialog.png
\endtable
The process of laying out widgets consists of creating the layout hierarchy
while setting as few widget size constraints as possible.
For a more technical perspective on Qt's layout classes, refer to the
\l{Layout Management} documentation.
*/
/*!
\page designer-quick-start.html
\contentspage {Qt Designer Manual}{Contents}
\title A Quick Start to Qt Designer
Using \QD involves \bold four basic steps:
\list 1
\o Choose your form and objects
\o Lay the objects out on the form
\o Connect the signals to the slots
\o Preview the form
\endlist
\image rgbController-screenshot.png
Suppose you would like to design a small widget (see screenshot above) that
contains the controls needed to manipulate Red, Green and Blue (RGB) values
-- a type of widget that can be seen everywhere in image manipulation
programs.
\table
\row
\i \inlineimage designer-choosing-form.png
\i \bold{Choosing a Form}
You start by choosing \gui Widget from the \gui{New Form} dialog.
\endtable
\table
\row
\i \inlineimage rgbController-arrangement.png
\i \bold{Placing Widgets on a Form}
Drag three labels, three spin boxes and three vertical sliders on to your
form. To change the label's default text, simply double-click on it. You
can arrange them according to how you would like them to be laid out.
\endtable
To ensure that they are laid out exactly like this in your program, you
need to place these widgets into a layout. We will do this in groups of
three. Select the "RED" label. Then, hold down \key Ctrl while you select
its corresponding spin box and slider. In the \gui{Form} menu, select
\gui{Lay Out in a Grid}.
\table
\row
\i \inlineimage rgbController-form-gridLayout.png
\i \inlineimage rgbController-selectForLayout.png
\endtable
Repeat the step for the other two labels along with their corresponding
spin boxes and sliders as well.
The next step is to combine all three layouts into one \bold{main layout}.
The main layout is the top level widget's (in this case, the QWidget)
layout. It is important that your top level widget has a layout; otherwise,
the widgets on your window will not resize when your window is resized. To
set the layout, \gui{Right click} anywhere on your form, outside of the
three separate layouts, and select \gui{Lay Out Horizontally}.
Alternatively, you could also select \gui{Lay Out in a Grid} -- you will
still see the same arrangement (shown below).
\image rgbController-final-layout.png
\note Main layouts cannot be seen on the form. To check if you have a main
layout installed, try resizing your form; your widgets should resize
accordingly. Alternatively, you can take a look at \QD's
\gui{Object Inspector}. If your top level widget does not have a layout,
you will see the broken layout icon next to it,
\inlineimage rgbController-no-toplevel-layout.png
.
When you click on the slider and drag it to a certain value, you want the
spin box to display the slider's position. To accomplish this behavior, you
need to connect the slider's \l{QAbstractSlider::}{valueChanged()} signal
to the spin box's \l{QSpinBox::}{setValue()} slot. You also need to make
the reverse connections, e.g., connect the spin box's \l{QSpinBox::}
{valueChanged()} signal to the slider's \l{QAbstractSlider::value()}
{setValue()} slot.
To do this, you have to switch to \gui{Edit Signals/Slots} mode, either by
pressing \key{F4} or selecting \gui{Edit Signals/Slots} from the \gui{Edit}
menu.
\table
\row
\i \inlineimage rgbController-signalsAndSlots.png
\i \bold{Connecting Signals to Slots}
Click on the slider and drag the cursor towards the spin box. The
\gui{Configure Connection} dialog, shown below, will pop up. Select the
correct signal and slot and click \gui OK.
\endtable
\image rgbController-configure-connection1.png
Repeat the step (in reverse order), clicking on the spin box and dragging
the cursor towards the slider, to connect the spin box's
\l{QSpinBox::}{valueChanged()} signal to the slider's
\l{QAbstractSlider::value()}{setValue()} slot.
You can use the screenshot below as a guide to selecting the correct signal
and slot.
\image rgbController-configure-connection2.png
Now that you have successfully connected the objects for the "RED"
component of the RGB Controller, do the same for the "GREEN" and "BLUE"
components as well.
Since RGB values range between 0 and 255, we need to limit the spin box
and slider to that particular range.
\table
\row
\i \inlineimage rgbController-property-editing.png
\i \bold{Setting Widget Properties}
Click on the first spin box. Within the \gui{Property Editor}, you will
see \l{QSpinBox}'s properties. Enter "255" for the
\l{QSpinBox::}{maximum} property. Then, click on the first vertical
slider, you will see \l{QAbstractSlider}'s properties. Enter "255" for
the \l{QAbstractSlider::}{maximum} property as well. Repeat this
process for the remaining spin boxes and sliders.
\endtable
Now, we preview your form to see how it would look in your application -
press \key{Ctrl + R} or select \gui Preview from the \gui Form menu. Try
dragging the slider - the spin box will mirror its value too (and vice
versa). Also, you can resize it to see how the layouts that are used to
manage the child widgets, respond to different window sizes.
*/
/*!
\page designer-editing-mode.html
\previouspage Getting to Know Qt Designer
\contentspage {Qt Designer Manual}{Contents}
\nextpage Using Layouts in Qt Designer
\title Qt Designer's Editing Modes
\QD provides four editing modes: \l{Qt Designer's Widget Editing Mode}
{Widget Editing Mode}, \l{Qt Designer's Signals and Slots Editing Mode}
{Signals and Slots Editing Mode}, \l{Qt Designer's Buddy Editing Mode}
{Buddy Editing Mode} and \l{Qt Designer's Tab Order Editing Mode}
{Tab Order Editing Mode}. When working with \QD, you will always be in one
of these four modes. To switch between modes, simply select it from the
\gui{Edit} menu or the toolbar. The table below describes these modes in
further detail.
\table
\header \i \i \bold{Editing Modes}
\row
\i \inlineimage designer-widget-tool.png
\i In \l{Qt Designer's Widget Editing Mode}{Edit} mode, we can
change the appearance of the form, add layouts, and edit the
properties of each widget. To switch to this mode, press
\key{F3}. This is \QD's default mode.
\row
\i \inlineimage designer-connection-tool.png
\i In \l{Qt Designer's Signals and Slots Editing Mode}
{Signals and Slots} mode, we can connect widgets together using
Qt's signals and slots mechanism. To switch to this mode, press
\key{F4}.
\row
\i \inlineimage designer-buddy-tool.png
\i In \l{Qt Designer's Buddy Editing Mode}{Buddy Editing Mode},
buddy widgets can be assigned to label widgets to help them
handle keyboard focus correctly.
\row
\i \inlineimage designer-tab-order-tool.png
\i In \l{Qt Designer's Tab Order Editing Mode}
{Tab Order Editing Mode}, we can set the order in which widgets
receive the keyboard focus.
\endtable
*/
/*!
\page designer-widget-mode.html
\previouspage Qt Designer's Editing Modes
\contentspage {Qt Designer Manual}{Contents}
\nextpage Qt Designer's Signals and Slots Editing Mode
\title Qt Designer's Widget Editing Mode
\image designer-editing-mode.png
In the Widget Editing Mode, objects can be dragged from the main window's
widget box to a form, edited, resized, dragged around on the form, and even
dragged between forms. Object properties can be modified interactively, so
that changes can be seen immediately. The editing interface is intuitive
for simple operations, yet it still supports Qt's powerful layout
facilities.
\tableofcontents
To create and edit new forms, open the \gui File menu and select
\gui{New Form...} or press \key{Ctrl+N}. Existing forms can also be edited
by selecting \gui{Open Form...} from the \gui File menu or pressing
\key{Ctrl+O}.
At any point, you can save your form by selecting the \gui{Save From As...}
option from the \gui File menu. The UI files saved by \QD contain
information about the objects used, and any details of signal and slot
connections between them.
\section1 Editing A Form
By default, new forms are opened in widget editing mode. To switch to Edit
mode from another mode, select \gui{Edit Widgets} from the \gui Edit menu
or press the \key F3 key.
Objects are added to the form by dragging them from the main widget box
and dropping them in the desired location on the form. Once there, they
can be moved around simply by dragging them, or using the cursor keys.
Pressing the \key Ctrl key at the same time moves the selected widget
pixel by pixel, while using the cursor keys alone make the selected widget
snap to the grid when it is moved. Objects can be selected by clicking on
them with the left mouse button. You can also use the \key Tab key to
change the selection.
### Screenshot of widget box, again
The widget box contains objects in a number of different categories, all of
which can be placed on the form as required. The only objects that require
a little more preparation are the \gui Container widgets. These are
described in further detail in the \l{Using Containers in Qt Designer}
chapter.
\target SelectingObjects
\table
\row
\i \inlineimage designer-selecting-widget.png
\i \bold{Selecting Objects}
Objects on the form are selected by clicking on them with the left
mouse button. When an object is selected, resize handles are shown at
each corner and the midpoint of each side, indicating that it can be
resized.
To select additional objects, hold down the \key Shift key and click on
them. If more than one object is selected, the current object will be
displayed with resize handles of a different color.
To move a widget within a layout, hold down \key Shift and \key Control
while dragging the widget. This extends the selection to the widget's
parent layout.
Alternatively, objects can be selected in the
\l{The Object Inspector}{Object Inspector}.
\endtable
When a widget is selected, normal clipboard operations such as cut, copy,
and paste can be performed on it. All of these operations can be done and
undone, as necessary.
The following shortcuts can be used:
\target ShortcutsForEditing
\table
\header \i Action \i Shortcut \i Description
\row
\i Cut
\i \key{Ctrl+X}
\i Cuts the selected objects to the clipboard.
\row
\i Copy
\i \key{Ctrl+C}
\i Copies the selected objects to the clipboard.
\row
\i Paste
\i \key{Ctrl+V}
\i Pastes the objects in the clipboard onto the form.
\row
\i Delete
\i \key Delete
\i Deletes the selected objects.
\row
\i Clone object
\i \key{Ctrl+drag} (leftmouse button)
\i Makes a copy of the selected object or group of objects.
\row
\i Preview
\i \key{Ctrl+R}
\i Shows a preview of the form.
\endtable
All of the above actions (apart from cloning) can be accessed via both the
\gui Edit menu and the form's context menu. These menus also provide
funcitons for laying out objects as well as a \gui{Select All} function to
select all the objects on the form.
Widgets are not unique objects; you can make as many copies of them as you
need. To quickly duplicate a widget, you can clone it by holding down the
\key Ctrl key and dragging it. This allows widgets to be copied and placed
on the form more quickly than with clipboard operations.
\target DragAndDrop
\table
\row
\i \inlineimage designer-dragging-onto-form.png
\i \bold{Drag and Drop}
\QD makes extensive use of the drag and drop facilities provided by Qt.
Widgets can be dragged from the widget box and dropped onto the form.
Widgets can also be "cloned" on the form: Holding down \key Ctrl and
dragging the widget creates a copy of the widget that can be dragged to
a new position.
It is also possible to drop Widgets onto the \l {The Object Inspector}
{Object Inspector} to handle nested layouts easily.
\endtable
\QD allows selections of objects to be copied, pasted, and dragged between
forms. You can use this feature to create more than one copy of the same
form, and experiment with different layouts in each of them.
\section2 The Property Editor
The Property Editor always displays properties of the currently selected
object on the form. The available properties depend on the object being
edited, but all of the widgets provided have common properties such as
\l{QObject::}{objectName}, the object's internal name, and
\l{QWidget::}{enabled}, the property that determines whether an
object can be interacted with or not.
\target EditingProperties
\table
\row
\i \inlineimage designer-property-editor.png
\i \bold{Editing Properties}
The property editor uses standard Qt input widgets to manage the
properties of jbects on the form. Textual properties are shown in line
edits, integer properties are displayed in spinboxes, boolean
properties are displayed in check boxes, and compound properties such
as colors and sizes are presented in drop-down lists of input widgets.
Modified properties are indicated with bold labels. To reset them, click
the arrow button on the right.
Changes in properties are applied to all selected objects that have the
same property.
\endtable
Certain properties are treated specially by the property editor:
\list
\o Compound properties -- properties that are made up of more than one
value -- are represented as nodes that can be expanded, allowing
their values to be edited.
\o Properties that contain a choice or selection of flags are edited
via combo boxes with checkable items.
\o Properties that allow access to rich data types, such as QPalette,
are modified using dialogs that open when the properties are edited.
QLabel and the widgets in the \gui Buttons section of the widget box
have a \c text property that can also be edited by double-clicking
on the widget or by pressing \gui F2. \QD interprets the backslash
(\\) character specially, enabling newline (\\n) characters to be
inserted into the text; the \\\\ character sequence is used to
insert a single backslash into the text. A context menu can also be
opened while editing, providing another way to insert special
characters and newlines into the text.
\endlist
\section2 Dynamic Properties
The property editor can also be used to add new
\l{QObject#Dynamic Properties}{dynamic properties} to both standard Qt
widgets and to forms themselves. Since Qt 4.4, dynamic properties are added
and removed via the property editor's toolbar, shown below.
\image designer-property-editor-toolbar.png
To add a dynamic property, clcik on the \gui Add button
\inlineimage designer-property-editor-add-dynamic.png
. To remove it, click on the \gui Remove button
\inlineimage designer-property-editor-remove-dynamic.png
instead. You can also sort the properties alphabetically and change the
color groups by clickinig on the \gui Configure button
\inlineimage designer-property-editor-configure.png
.
\section2 The Object Inspector
\table
\row
\i \inlineimage designer-object-inspector.png
\i \bold{The Object Inspector}
The \gui{Object Inspector} displays a hierarchical list of all the
objects on the form that is currently being edited. To show the child
objects of a container widget or a layout, click the handle next to the
object label.
Each object on a form can be selected by clicking on the corresponding
item in the \gui{Object Inspector}. Right-clicking opens the form's
context menu. These features can be useful if you have many overlapping
objects. To locate an object in the \gui{Object Inspector}, use
\key{Ctrl+F}.
Since Qt 4.4, double-clicking on the object's name allows you to change
the object's name with the in-place editor.
Since Qt 4.5, the \gui{Object Inspector} displays the layout state of
the containers. The broken layout icon ###ICON is displayed if there is
something wrong with the layouts.
\endtable
*/
/*!
\page designer-layouts.html
\previouspage Qt Designer's Widget Editing Mode
\contentspage
\nextpage Qt Designer's Signals and Slots Editing Mode
\title Using Layouts in Qt Designer
Before a form can be used, the objects on the form need to be placed into
layouts. This ensures that the objects will be displayed properly when the
form is previewed or used in an application. Placing objects in a layout
also ensures that they will be resized correctly when the form is resized.
\tableofcontents
\section1 Applying and Breaking Layouts
The simplest way to manage objects is to apply a layout to a group of
existing objects. This is achieved by selecting the objects that you need
to manage and applying one of the standard layouts using the main toolbar,
the \gui Form menu, or the form's context menu.
Once widgets have been inserted into a layout, it is not possible to move
and resize them individually because the layout itself controls the
geometry of each widget within it, taking account of the hints provided by
spacers. Instead, you must either break the layout and adjust each object's
geometry manually, or you can influence the widget's geometry by resizing
the layout.
To break the layout, press \key{Ctrl+0} or choose \gui{Break Layout} from
the form's context menu, the \gui Form menu or the main toolbar. You can
also add and remove spacers from the layout to influence the geometries of
the widgets.
\target InsertingObjectsIntoALayout
\table
\row
\i \inlineimage designer-layout-inserting.png
\i \bold{Inserting Objects into a Layout}
Objects can be inserted into an existing layout by dragging them from
their current positions and dropping them at the required location. A
blue cursor is displayed in the layout as an object is dragged over
it to indicate where the object will be added.
\endtable
\section2 Setting A Top Level Layout
The form's top level layout can be set by clearing the slection (click the
left mouse button on the form itself) and applying a layout. A top level
layout is necessary to ensure that your widgets will resize correctly when
its window is resized. To check if you have set a top level layout, preview
your widget and attempt to resize the window by dragging the size grip.
\table
\row
\i \inlineimage designer-set-layout.png
\i \bold{Applying a Layout}
To apply a layout, you can select your choice of layout from the
toolbar shown on the left, or from the context menu shown below.
\endtable
\image designer-set-layout2.png
\section2 Horizontal and Vertical Layouts
The simplest way to arrange objects on a form is to place them in a
horizontal or vertical layout. Horizontal layouts ensure that the widgets
within are aligned horizontally; vertical layouts ensure that they are
aligned vertically.
Horizontal and vertical layouts can be combined and nested to any depth.
However, if you need more control over the placement of objects, consider
using the grid layout.
\section3 The Grid Layout
Complex form layouts can be created by placing objects in a grid layout.
This kind of layout gives the form designer much more freedom to arrange
widgets on the form, but can result in a much less flexible layout.
However, for some kinds of form layout, a grid arrangement is much more
suitable than a nested arrangement of horizontal and vertical layouts.
\section3 Splitter Layouts
Another common way to manage the layout of objects on a form is to place
them in a splitter. These splitters arrange the objects horizontally or
vertically in the same way as normal layouts, but also allow the user to
adjust the amount of space allocated to each object.
\image designer-splitter-layout.png
Although QSplitter is a container widget, \QD treats splitter objects as
layouts that are applied to existing widgets. To place a group of widgets
into a splitter, select them
\l{Qt Designer's Widget Editing Mode#SelectingObjects}{as described here}
then apply the splitter layout by using the appropriate toolbar button,
keyboard shortcut, or \gui{Lay out} context menu entry.
\section3 The Form Layout
Since Qt 4.4, another layout class has been included -- QFormLayout. This
class manages widgets in a two-column form; the left column holds labels
and the right column holds field widgets such as line edits, spin boxes,
etc. The QFormLayout class adheres to various platform look and feel
guidelines and supports wrapping for long rows.
\image designer-form-layout.png
The UI file above results in the previews shown below.
\table
\header
\i Windows XP
\i Mac OS X
\i Cleanlooks
\row
\i \inlineimage designer-form-layout-windowsXP.png
\i \inlineimage designer-form-layout-macintosh.png
\i \inlineimage designer-form-layout-cleanlooks.png
\endtable
\section2 Shortcut Keys
In addition to the standard toolbar and context menu entries, there is also
a set of keyboard shortcuts to apply layouts on widgets.
\target LayoutShortcuts
\table
\header
\i Layout
\i Shortcut
\i Description
\row
\i Horizontal
\i \key{Ctrl+1}
\i Places the selected objects in a horizontal layout.
\row
\i Vertical
\i \key{Ctrl+2}
\i Places the selected objects in a vertical layout.
\row
\i Grid
\i \key{Ctrl+5}
\i Places the selected objects in a grid layout.
\row
\i Form
\i \key{Ctrl+6}
\i Places the selected objects in a form layout.
\row
\i Horizontal splitter
\i \key{Ctrl+3}
\i Creates a horizontal splitter and places the selected objects
inside it.
\row
\i Vertical splitter
\i \key{Ctrl+4}
\i Creates a vertical splitter and places the selected objects
inside it.
\row
\i Adjust size
\i \key{Ctrl+J}
\i Adjusts the size of the layout to ensure that each child object
has sufficient space to display its contents. See
QWidget::adjustSize() for more information.
\endtable
\note \key{Ctrl+0} is used to break a layout.
*/
/*!
\page designer-preview.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Using Layouts in Qt Designer
\nextpage Qt Designer's Buddy Editing Mode
\title Saving, Previewing and Printing Forms in Qt Designer
Although \QD's forms are accurate representations of the components being
edited, it is useful to preview the final appearance while editing. This
feature can be activated by opening the \gui Form menu and selecting
\gui Preview, or by pressing \key{Ctrl+R} when in the form.
\image designer-dialog-preview.png
The preview shows exactly what the final component will look like when used
in an application.
Since Qt 4.4, it is possible to preview forms with various skins - default
skins, skins created with Qt Style Sheets or device skins. This feature
simulates the effect of calling \c{QApplication::setStyleSheet()} in the
application.
To preview your form with skins, open the \gui Edit menu and select
\gui{Preferences...}
You will see the dialog shown below:
\image designer-preview-style.png
The \gui{Print/Preview Configuration} checkbox must be checked to activate
previews of skins. You can select the styles provided from the \gui{Style}
drop-down box.
\image designer-preview-style-selection.png
Alternatively, you can preview custom style sheet created with Qt Style
Sheets. The figure below shows an example of Qt Style Sheet syntax and the
corresponding output.
\image designer-preview-stylesheet.png
Another option would be to preview your form with device skins. A list of
generic device skins are available in \QD, however, you may also use
other QVFB skins with the \gui{Browse...} option.
\image designer-preview-deviceskin-selection.png
\section1 Viewing the Form's Code
Since Qt 4.4, it is possible to view code generated by the User Interface
Compiler (uic) for the \QD form.
\image designer-form-viewcode.png
Select \gui{View Code...} from the \gui{Form} menu and a dialog with the
generated code will be displayed. The screenshot below is an example of
code generated by the \c{uic}.
\image designer-code-viewer.png
\section1 Saving and Printing the Form
Forms created in \QD can be saved to an image or printed.
\table
\row
\i \inlineimage designer-file-menu.png
\i \bold{Saving Forms}
To save a form as an image, choose the \gui{Save Image...} option. The file
will be saved in \c{.png} format.
\bold{Printing Forms}
To print a form, select the \gui{Print...} option.
\endtable
*/
/*!
\page designer-connection-mode.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Using Layouts in Qt Designer
\nextpage Qt Designer's Buddy Editing Mode
\title Qt Designer's Signals and Slots Editing Mode
\image designer-connection-mode.png
In \QD's signals and slots editing mode, you can connect objects in a form
together using Qt's signals and slots mechanism. Both widgets and layouts
can be connected via an intuitive connection interface, using the menu of
compatible signals and slots provided by \QD. When a form is saved, all
connections are preserved so that they will be ready for use when your
project is built.
\tableofcontents
For more information on Qt's signals and sltos mechanism, refer to the
\l{Signals and Slots} document.
\section1 Connecting Objects
To begin connecting objects, enter the signals and slots editing mode by
opening the \gui Edit menu and selecting \gui{Edit Signals/Slots}, or by
pressing the \key F4 key.
All widgets and layouts on the form can be connected together. However,
spacers just provide spacing hints to layouts, so they cannot be connected
to other objects.
\target HighlightedObjects
\table
\row
\i \inlineimage designer-connection-highlight.png
\i \bold{Highlighted Objects}
When the cursor is over an object that can be used in a connection, the
object will be highlighted.
\endtable
To make a connectionn, press the left mouse button and drag the cursor
towards the object you want to connect it to. As you do this, a line will
extend from the source object to the cursor. If the cursor is over another
object on the form, the line will end with an arrow head that points to the
destination object. This indicates that a connection will be made between
the two objects when you release the mouse button.
You can abandon the connection at any point while you are dragging the
connection path by pressing \key{Esc}.
\target MakingAConnection
\table
\row
\i \inlineimage designer-connection-making.png
\i \bold{Making a Connection}
The connection path will change its shape as the cursor moves around
the form. As it passes over objects, they are highlighted, indicating
that they can be used in a signal and slot connection. Release the
mouse button to make the connection.
\endtable
The \gui{Configure Connection} dialog (below) is displayed, showing signals
from the source object and slots from the destination object that you can
use.
\image designer-connection-dialog.png
To complete the connection, select a signal from the source object and a
slot from the destination object, then click \key OK. Click \key Cancel if
you wish to abandon the connection.
\note If the \gui{Show all signals and slots} checkbox is selected, all
available signals from the source object will be shown. Otherwise, the
signals and slots inherited from QWidget will be hidden.
You can make as many connections as you like between objects on the form;
it is possible to connect signals from objects to slots in the form itself.
As a result, the signal and slot connections in many dialogs can be
completely configured from within \QD.
\target ConnectingToTheForm
\table
\row
\i \inlineimage designer-connection-to-form.png
\i \bold{Connecting to a Form}
To connect an object to the form itself, simply position the cursor
over the form and release the mouse button. The end point of the
connection changes to the electrical "ground" symbol.
\endtable
\section1 Editing and Deleting Connections
By default, connection paths are created with two labels that show the
signal and slot involved in the connection. These labels are usually
oriented along the line of the connection. You can move them around inside
their host widgets by dragging the red square at each end of the connection
path.
\target ConnectionEditor
\table
\row
\i \inlineimage designer-connection-editor.png
\i \bold{The Signal/Slot Editor}
The signal and slot used in a connection can be changed after it has
been set up. When a connection is configured, it becomes visible in
\QD's signal and slot editor where it can be further edited. You can
also edit signal/slot connections by double-clicking on the connection
path or one of its labels to display the Connection Dialog.
\endtable
\target DeletingConnections
\table
\row
\i \inlineimage designer-connection-editing.png
\i \bold{Deleting Connections}
The whole connection can be selected by clicking on any of its path
segments. Once selected, a connection can be deleted with the
\key Delete key, ensuring that it will not be set up in the UI
file.
\endtable
*/
/*!
\page designer-buddy-mode.html
\contentspage{Qt Designer Manual}{Contents}
\previouspage Qt Designer's Signals and Slots Editing Mode
\nextpage Qt Designer's Tab Order Editing Mode
\title Qt Designer's Buddy Editing Mode
\image designer-buddy-mode.png
One of the most useful basic features of Qt is the support for buddy
widgets. A buddy widget accepts the input focus on behalf of a QLabel when
the user types the label's shortcut key combination. The buddy concept is
also used in Qt's \l{Model/View Programming}{model/view} framework.
\section1 Linking Labels to Buddy Widgets
To enter buddy editing mode, open the \gui Edit menu and select
\gui{Edit Buddies}. This mode presents the widgets on the form in a similar
way to \l{Qt Designer's Signals and Slots Editing Mode}{signals and slots
editing mode} but in this mode, connections must start at label widgets.
Ideally, you should connect each label widget that provides a shortcut with
a suitable input widget, such as a QLineEdit.
\target MakingBuddies
\table
\row
\i \inlineimage designer-buddy-making.png
\i \bold{Making Buddies}
To define a buddy widget for a label, click on the label, drag the
connection to another widget on the form, and release the mouse button.
The connection shown indicates how input focus is passed to the buddy
widget. You can use the form preview to test the connections between
each label and its buddy.
\endtable
\section1 Removing Buddy Connections
Only one buddy widget can be defined for each label. To change the buddy
used, it is necessary to delete any existing buddy connection before you
create a new one.
Connections between labels and their buddy widgets can be deleted in the
same way as signal-slot connections in signals and slots editing mode:
Select the buddy connection by clicking on it and press the \key Delete
key. This operation does not modify either the label or its buddy in any
way.
*/
/*!
\page designer-tab-order.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Qt Designer's Buddy Editing Mode
\nextpage Using Containers in Qt Designer
\title Qt Designer's Tab Order Editing Mode
\image designer-tab-order-mode.png
Many users expect to be able to navigate between widgets and controls
using only the keyboard. Qt lets the user navigate between input widgets
with the \key Tab and \key{Shift+Tab} keyboard shortcuts. The default
\e{tab order} is based on the order in which widgets are constructed.
Although this order may be sufficient for many users, it is often better
to explicitly specify the tab order to make your application easier to
use.
\section1 Setting the Tab Order
To enter tab order editing mode, open the \gui Edit menu and select
\gui{Edit Tab Order}. In this mode, each input widget in the form is shown
with a number indicating its position in the tab order. So, if the user
gives the first input widget the input focus and then presses the tab key,
the focus will move to the second input widget, and so on.
The tab order is defined by clicking on each of the numbers in the correct
order. The first number you click will change to red, indicating the
currently edited position in the tab order chain. The widget associated
with the number will become the first one in the tab order chain. Clicking
on another widget will make it the second in the tab order, and so on.
Repeat this process until you are satisfied with the tab order in the form
-- you do not need to click every input widget if you see that the
remaining widgets are already in the correct order. Numbers, for which you
already set the order, change to green, while those which are not clicked
yet, remain blue.
If you make a mistake, simply double click outside of any number or choose
\gui{Restart} from the form's context menu to start again. If you have many
widgets on your form and would like to change the tab order in the middle or
at the end of the tab order chain, you can edit it at any position. Press
\key{Ctrl} and click the number from which you want to start.
Alternatively, choose \gui{Start from Here} in the context menu.
*/
/*!
\page designer-using-containers.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Qt Designer's Tab Order Editing Mode
\nextpage Creating Main Windows in Qt Designer
\title Using Containers in Qt Designer
Container widgets provide high level control over groups of objects on a
form. They can be used to perform a variety of functions, such as managing
input widgets, providing paged and tabbed layouts, or just acting as
decorative containers for other objects.
\image designer-widget-morph.png
\QD provides visual feedback to help you place objects inside your
containers. When you drag an object from the widget box (or elsewhere) on
the form, each container will be highlighted when the cursor is positioned
over it. This indicates that you can drop the object inside, making it a
child object of the container. This feedback is important because it is
easy to place objects close to containers without actually placing them
inside. Both widgets and spacers can be used inside containers.
Stacked widgets, tab widgets, and toolboxes are handled specially in \QD.
Normally, when adding pages (tabs, pages, compartments) to these containers
in your own code, you need to supply existing widgets, either as
placeholders or containing child widgets. In \QD, these are automatically
created for you, so you can add child objects to each page straight away.
Each container typically allows its child objects to be arranged in one or
more layouts. The type of layout management provided depends on each
container, although setting the layout is usually just a matter of
selecting the container by clicking it, and applying a layout. The table
below shows a list of available containers.
\table
\row
\i \inlineimage designer-containers-frame.png
\i \bold Frames
Frames are used to enclose and group widgets, as well as to provide
decoration. They are used as the foundation for more complex
containers, but they can also be used as placeholders in forms.
The most important properties of frames are \c frameShape,
\c frameShadow, \c lineWidth, and \c midLineWidth. These are described
in more detail in the QFrame class description.
\row
\i \inlineimage designer-containers-groupbox.png
\i \bold{Group Boxes}
Group boxes are usually used to group together collections of
checkboxes and radio buttons with similar purposes.
Among the significant properties of group boxes are \c title, \c flat,
\c checkable, and \c checked. These are demonstrated in the
\l{widgets/groupbox}{Group Box} example, and described in the QGroupBox
class documentation. Each group box can contain its own layout, and
this is necessary if it contains other widgets. To add a layout to the
group box, click inside it and apply the layout as usual.
\row
\i \inlineimage designer-containers-stackedwidget.png
\i \bold{Stacked Widgets}
Stacked widgets are collections of widgets in which only the topmost
layer is visible. Control over the visible layer is usually managed by
another widget, such as combobox, using signals and slots.
\QD shows arrows in the top-right corner of the stack to allow you to
see all the widgets in the stack when designing it. These arrows do not
appear in the preview or in the final component. To navigate between
pages in the stack, select the stacked widget and use the
\gui{Next Page} and \gui{Previous Page} entries from the context menu.
The \gui{Insert Page} and \gui{Delete Page} context menu options allow
you to add and remove pages.
\row
\i \inlineimage designer-containers-tabwidget.png
\i \bold{Tab Widgets}
Tab widgets allow the developer to split up the contents of a widget
into different labelled sections, only one of which is displayed at any
given time. By default, the tab widget contains two tabs, and these can
be deleted or renamed as required. You can also add additional tabs.
To delete a tab:
\list
\o Click on its label to make it the current tab.
\o Select the tab widget and open its context menu.
\o Select \gui{Delete Page}.
\endlist
To add a new tab:
\list
\o Select the tab widget and open its context menu.
\o Select \gui{Insert Page}.
\o You can add a page before or after the \e current page. \QD
will create a new widget for that particular tab and insert it
into the tab widget.
\o You can set the title of the current tab by changing the
\c currentTabText property in the \gui{Property Editor}.
\endlist
\row
\i \inlineimage designer-containers-toolbox.png
\i \bold{ToolBox Widgets}
Toolbox widgets provide a series of pages or compartments in a toolbox.
They are handled in a way similar to stacked widgets.
To rename a page in a toolbox, make the toolbox your current pange and
change its \c currentItemText property from the \gui{Property Editor}.
To add a new page, select \gui{Insert Page} from the toolbox widget's
context menu. You can add the page before or after the current page.
To delete a page, select \gui{Delete Page} from the toolbox widget's
context menu.
\row
\i \inlineimage designer-containers-dockwidget.png
\i \bold{Dock Widgets}
Dock widgets are floating panels, often containing input widgets and
more complex controls, that are either attached to the edges of the
main window in "dock areas", or floated as independent tool windows.
Although dock widgets can be added to any type of form, they are
typically used with forms created from the
\l{Creating Main Windows in Qt Designer}{main window template}.
\endtable
*/
/*!
\page designer-creating-mainwindows.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Using Containers in Qt Designer
\nextpage Editing Resources with Qt Designer
\title Creating Main Windows in Qt Designer
\QD can be used to create user interfaces for different purposes, and
it provides different kinds of form templates for each user interface. The
main window template is used to create application windows with menu bars,
toolbars, and dock widgets.
\omit
\image designer-mainwindow-example.png
\endomit
Create a new main window by opening the \gui File menu and selecting the
\gui{New Form...} option, or by pressing \key{Ctrl+N}. Then, select the
\gui{Main Window} template. This template provides a main application
window containing a menu bar and a toolbar by default -- these can be
removed if they are not required.
If you remove the menu bar, a new one can be created by selecting the
\gui{Create Menu Bar} option from the context menu, obtained by
right-clicking within the main window form.
An application can have only \bold one menu bar, but \bold several
toolbars.
\section1 Menus
Menus are added to the menu bar by modifying the \gui{Type Here}
placeholders. One of these is always present for editing purposes, and
will not be displayed in the preview or in the finished window.
Once created, the properties of a menu can be accessed using the
\l{Qt Designer's Widget Editing Mode#The Property Editor}{Property Editor},
and each menu can be accessed for this purpose via the
\l{Qt Designer's Widget Editing Mode#The Object Inspector}{The Object Inspector}.
Existing menus can be removed by opening a context menu over the label in
the menu bar, and selecting \gui{Remove Menu 'menu_name'}.
\target CreatingAMenu
\raw HTML
\endraw
\inlineimage designer-creating-menu1.png
\inlineimage designer-creating-menu2.png
\br
\inlineimage designer-creating-menu3.png
\inlineimage designer-creating-menu4.png
\raw HTML
\endraw
\section2 Creating a Menu
Double-click the placeholder item to begin editing. The menu text,
displayed using a line edit, can be modified.
Insert the required text for the new menu. Inserting an
ampersand character (&) causes the letter following it to be
used as a mnemonic for the menu.
Press \key Return or \key Enter to accept the new text, or press
\key Escape to reject it. You can undo the editing operation later if
required.
\raw HTML
\endraw
Menus can also be rearranged in the menu bar simply by dragging and
dropping them in the preferred location. A vertical red line indicates the
position where the menu will be inserted.
Menus can contain any number of entries and separators, and can be nested
to the required depth. Adding new entries to menus can be achieved by
navigating the menu structure in the usual way.
\target CreatingAMenuEntry
\raw HTML
\endraw
\inlineimage designer-creating-menu-entry1.png
\inlineimage designer-creating-menu-entry2.png
\br
\inlineimage designer-creating-menu-entry3.png
\inlineimage designer-creating-menu-entry4.png
\raw HTML
\endraw
\section2 Creating a Menu Entry
Double-click the \gui{Type Here} placeholder to begin editing, or
double-click \gui{Add Separator} to insert a new separator line after
the last entry in the menu.
The menu entry's text is displayed using a line edit, and can be
modified.
Insert the required text for the new entry, optionally using
the ampersand character (&) to mark the letter to use as a
mnemonic for the entry.
Press \key Return or \key Enter to accept the new text, or press
\key Escape to reject it. The action created for this menu entry will
be accessible via the \l{#TheActionEditor}{Action Editor}, and any
associated keyboard shortcut can be set there.
\raw HTML
\endraw
Just like with menus, entries can be moved around simply by dragging and
dropping them in the preferred location. When an entry is dragged over a
closed menu, the menu will open to allow it to be inserted there. Since
menu entries are based on actions, they can also be dropped onto toolbars,
where they will be displayed as toolbar buttons.
\section1 Toolbars
\raw HTML
\endraw
\inlineimage designer-creating-toolbar.png
\raw HTML
\endraw
\section2 Creating and Removing a Toolbar
Toolbars are added to a main window in a similar way to the menu bar:
Select the \gui{Add Tool Bar} option from the form's context menu.
Alternatively, if there is an existing toolbar in the main window, you can
click the arrow on its right end to create a new toolbar.
Toolbars are removed from the form via an entry in the toolbar's context
menu.
\raw HTML
\endraw
\section2 Adding and Removing Toolbar Buttons
Toolbar buttons are created as actions in the
\l{#TheActionEditor}{Action Editor} and dragged onto the toolbar.
Since actions can be represented by menu entries and toolbar buttons,
they can be moved between menus and toolbars.
\raw HTML
\endraw
\inlineimage designer-adding-toolbar-action.png
\inlineimage designer-removing-toolbar-action.png
\raw HTML
\endraw
To share an action between a menu and a toolbar, drag its icon from the
action editor to the toolbar rather than from the menu where its entry is
located. See \l{#Adding an Action}{Adding an Action} for more information
about this process.
Toolbar buttons are removed via the toolbar's context menu.
\raw HTML
\endraw
\section1 Actions
With the menu bar and the toolbars in place, it's time to populate them
with actions. New actions for both menus and toolbars are created in the
action editor window, simplifying the creation and management of actions.
\target TheActionEditor
\raw HTML
\endraw
\inlineimage designer-action-editor.png
\raw HTML
\endraw
\section2 The Action Editor
Enable the action editor by opening the \gui Tools menu, and switching
on the \gui{Action Editor} option.
The action editor allows you to create \gui New actions and \gui Delete
actions. It also provides a search function, \gui Filter, using the
action's text.
\QD's action editor can be viewed in the classic \gui{Icon View} and
\gui{Detailed View}. The screenshot below shows the action editor in
\gui{Detailed View}. You can also copy and paste actions between menus,
toolbars and forms.
\raw HTML
\endraw
\section2 Creating an Action
To create an action, use the action editor's \gui New button, which will
then pop up an input dialog. Provide the new action with a \gui Text --
this is the text that will appear in a menu entry and as the action's
tooltip. The text is also automatically added to an "action" prefix,
creating the action's \gui{Object Name}.
In addition, the dialog provides the option of selecting an \gui Icon for
the action, as well as removing the current icon.
Once the action is created, it can be used wherever actions are applicable.
\raw HTML
\endraw
\target AddingAnAction
\raw HTML
\endraw
\inlineimage designer-adding-menu-action.png
\inlineimage designer-adding-toolbar-action.png
\raw HTML
\endraw
\section2 Adding an Action
To add an action to a menu or a toolbar, simply press the left mouse
button over the action in the action editor, and drag it to the
preferred location.
\QD provides highlighted guide lines that tell you where the action
will be added. Release the mouse button to add the action when you have
found the right spot.
\raw HTML
\endraw
\section1 Dock Widgets
Since dock widgets are \l{Using Containers in Qt Designer}
{container widgets}, they can be added to a form in the usuasl way. Once
added to a form, dock widgets are not placed in any particular dock area by
default; you need to set the \gui{docked} property to true for each widget
and choose an appropriate value for its \gui{dockWidgetArea} property.
\target AddingADockWidget
\raw HTML
\endraw
\inlineimage designer-adding-dockwidget.png
\raw HTML
\endraw
\section2 Adding a Dock Widget
To add a dock widget to a form, drag one from the \gui Containers section
of the widget box, and drop it onto the main form area. Do not add the
dock widget to an existing layout. Instead, open the \gui{Property Editor}
and enable the \gui{docked} property to place it in a dock area.
Note that it is sometimes easier to configure a dock widget if it is added
to a form before a layout is applied to the central widget. For example,
it is possible to undock it and resize it, making it more convenient to
add child widgets.
Dock widgets can be optionally floated as independent tool windows.
Hence, it is useful to give them window titles by setting their
\l{QDockWidget::}{windowTitle} property. This also helps to identify them on the
form.
\raw HTML
\endraw
*/
/*!
\page designer-resources.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Creating Main Windows in Qt Designer
\nextpage Using Stylesheets with Qt Designer
\title Editing Resources with Qt Designer
\image designer-resources-editing.png
\QD fully supports the \l{The Qt Resource System}{Qt Resource System},
enabling resources to be specified together with forms as they are
designed. To aid designers and developers manage resources for their
applications, \QD's resource editor allows resources to be defined on a
per-form basis. In other words, each form can have a separate resource
file.
\section1 Defining a Resource File
To specify a resource file you must enable the resource editor by opening
the \gui Tools menu, and switching on the \gui{Resource Browser} option.
\target ResourceFiles
\table
\row
\i \inlineimage designer-resource-browser.png
\i \bold{Resource Files}
Within the resource browser, you can open existing resource files or
create new ones. Click the \gui{Edit Resources} button
\inlineimage designer-edit-resources-button.png
to edit your resources. To reload resources, click on the \gui Reload
button
\inlineimage designer-reload-resources-button.png
.
\endtable
Once a resource file is loaded, you can create or remove entries in it
using the given \gui{Add Files}
\inlineimage designer-add-resource-entry-button.png
and \gui{Remove Files}
\inlineimage designer-remove-resource-entry-button.png
buttons, and specify resources (e.g., images) using the \gui{Add Files}
button
\inlineimage designer-add-files-button.png
. Note that these resources must reside within the current resource file's
directory or one of its subdirectories.
\target EditResource
\table
\row
\i \inlineimage designer-edit-resource.png
\i \bold{Editing Resource Files}
Press the
\inlineimage designer-add-resource-entry-button.png
button to add a new resource entry to the file. Then use the
\gui{Add Files} button
\inlineimage designer-add-files-button.png
to specify the resource.
You can remove resources by selecting the corresponding entry in the
resource editor, and pressing the
\inlineimage designer-remove-resource-entry-button.png
button.
\endtable
\section1 Using the Resources
Once the resources are defined you can use them actively when composing
your form. For example, you might want to create a tool button using an
icon specified in the resource file.
\target UsingResources
\table
\row
\i \inlineimage designer-resources-using.png
\i \bold{Using Resources}
When changing properties with values that may be defined within a
resource file, \QD's property editor allows you to specify a resource
in addition to the option of selecting a source file in the ordinary
way.
\row
\i \inlineimage designer-resource-selector.png
\i \bold{Selecting a Resource}
You can open the resource selector by clicking \gui{Choose Resource...}
to add resources any time during the design process.
\omit
... check with Friedemann
To quickly assign icon pixmaps to actions or pixmap properties, you may
drag the pixmap from the resource editor to the action editor, or to the
pixmap property in the property editor.
\endomit
\endtable
*/
/*!
\page designer-stylesheet.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Editing Resources with Qt Designer
\nextpage Using a Designer UI File in Your Application
\title Using Stylesheets with Qt Designer
Since Qt 4.2, it is possible to edit stylesheets in \QD with the stylesheet
editor.
\target UsingStylesheets
\table
\row
\i \inlineimage designer-stylesheet-options.png
\bold{Setting a Stylesheet}
The stylesheet editor can be accessed by right-clicking a widget
and selecting \gui{Change styleSheet...}
\row
\i \inlineimage designer-stylesheet-usage.png
\endtable
*/
/*!
\page designer-using-a-ui-file.html
\previouspage Using Stylesheets with Qt Designer
\contentspage {Qt Designer Manual}{Contents}
\nextpage Using Custom Widgets with Qt Designer
\title Using a Designer UI File in Your Application
With Qt's integrated build tools, \l{qmake Manual}{qmake} and \l uic, the
code for user interface components created with \QD is automatically
generated when the rest of your application is built. Forms can be included
and used directly from your application. Alternatively, you can use them to
extend subclasses of standard widgets. These forms can be processed at
compile time or at run time, depending on the approach used.
\tableofcontents
\section1 Compile Time Form Processing
A compile time processed form can be used in your application with one of
the following approaches:
\list
\o The Direct Approach: you construct a widget to use as a placeholder
for the component, and set up the user interface inside it.
\o The Single Inheritance Approach: you subclass the form's base class
(QWidget or QDialog, for example), and include a private instance
of the form's user interface object.
\o The MultipleInheritance Approach: you subclass both the form's base
class and the form's user interface object. This allows the widgets
defined in the form to be used directly from within the scope of
the subclass.
\endlist
\section2 The Direct Approach
To demonstrate how to use user interface (UI) files straight from
\QD, we create a simple Calculator Form application. This is based on the
original \l{Calculator Form Example}{Calculator Form} example.
The application consists of one source file, \c main.cpp and a UI
file.
The \c{calculatorform.ui} file designed with \QD is shown below:
\image directapproach-calculatorform.png
We will use \c qmake to build the executable, so we need to write a
\c{.pro} file:
\snippet doc/src/snippets/uitools/calculatorform/calculatorform.pro 0
The special feature of this file is the \c FORMS declaration that tells
\c qmake which files to process with \c uic. In this case, the
\c calculatorform.ui file is used to create a \c ui_calculatorform.h file
that can be used by any file listed in the \c SOURCES declaration. To
ensure that \c qmake generates the \c ui_calculatorform.h file, we need to
include it in a file listed in \c SOURCES. Since we only have \c main.cpp,
we include it there:
\snippet doc/src/snippets/uitools/calculatorform/main.cpp 0
This include is an additional check to ensure that we do not generate code
for UI files that are not used.
The \c main function creates the calculator widget by constructing a
standard QWidget that we use to host the user interface described by the
\c calculatorform.ui file.
\snippet doc/src/snippets/uitools/calculatorform/main.cpp 1
In this case, the \c{Ui::CalculatorForm} is an interface description object
from the \c ui_calculatorform.h file that sets up all the dialog's widgets
and the connections between its signals and slots.
This approach provides a quick and easy way to use simple, self-contained
components in your applications, but many componens created with \QD will
require close integration with the rest of the application code. For
instance, the \c CalculatorForm code provided above will compile and run,
but the QSpinBox objects will not interact with the QLabel as we need a
custom slot to carry out the add operation and display the result in the
QLabel. To achieve this, we need to subclass a standard Qt widget (known as
the single inheritance approach).
\section2 The Single Inheritance Approach
In this approach, we subclass a Qt widget and set up the user interface
from within the constructor. Components used in this way expose the widgets
and layouts used in the form to the Qt widget subclass, and provide a
standard system for making signal and slot connections between the user
interface and other objects in your application.
This approach is used in the \l{Calculator Form Example}{Calculator Form}
example.
To ensure that we can use the user interface, we need to include the header
file that \c uic generates before referring to \c{Ui::CalculatorForm}:
\snippet examples/designer/calculatorform/calculatorform.h 0
This means that the \c{.pro} file must be updated to include
\c{calculatorform.h}:
\snippet examples/designer/calculatorform/calculatorform.pro 0
The subclass is defined in the following way:
\snippet examples/designer/calculatorform/calculatorform.h 1
The important feature of the class is the private \c ui object which
provides the code for setting up and managing the user interface.
The constructor for the subclass constructs and configures all the widgets
and layouts for the dialog just by calling the \c ui object's \c setupUi()
function. Once this has been done, it is possible to modify the user
interface as needed.
\snippet examples/designer/calculatorform/calculatorform.cpp 0
We can connect signals and slots in user interface widgets in the usual
way, taking care to prefix the \c ui object to each widget used.
The advantages of this approach are its simple use of inheritance to
provide a QWidget-based interface, and its encapsulation of the user
interface widget variables within the \c ui data member. We can use this
method to define a number of user interfaces within the same widget, each
of which is contained within its own namespace, and overlay (or compose)
them. This approach can be used to create individual tabs from existing
forms, for example.
\section2 The Multiple Inheritance Approach
Forms created with \QD can be subclassed together with a standard
QWidget-based class. This approach makes all the user interface components
defined in the form directly accessible within the scope of the subclass,
and enables signal and slot connections to be made in the usual way with
the \l{QObject::connect()}{connect()} function.
This approach is used in the \l{Multiple Inheritance Example}
{Multiple Inheritance} example.
We need to include the header file that \c uic generates from the
\c calculatorform.ui file:
\snippet examples/uitools/multipleinheritance/calculatorform.h 0
The class is defined in a similar way to the one used in the
\l{The Single Inheritance Approach}{single inheritance approach}, except that
this time we inherit from \e{both} QWidget and \c{Ui::CalculatorForm}:
\snippet examples/uitools/multipleinheritance/calculatorform.h 1
We inherit \c{Ui::CalculatorForm} privately to ensure that the user
interface objects are private in our subclass. We can also inherit it with
the \c public or \c protected keywords in the same way that we could have
made \c ui public or protected in the previous case.
The constructor for the subclass performs many of the same tasks as the
constructor used in the \l{The Single Inheritance Approach}
{single inheritance} example:
\snippet examples/uitools/multipleinheritance/calculatorform.cpp 0
In this case, the widgets used in the user interface can be accessed in the
same say as a widget created in code by hand. We no longer require the
\c{ui} prefix to access them.
Subclassing using multiple inheritance gives us more direct access to the
contents of the form, is slightly cleaner than the single inheritance
approach, but does not conveniently support composition of multiple user
interfaces.
\section1 Run Time Form Processing
Alternatively, forms can be processed at run time, producing dynamically-
generated user interfaces. This can be done using the QtUiTools module
that provides the QUiLoader class to handle forms created with \QD.
\section2 The UiTools Approach
A resource file containing a UI file is required to process forms at
run time. Also, the application needs to be configured to use the QtUiTools
module. This is done by including the following declaration in a \c qmake
project file, ensuring that the application is compiled and linked
appropriately.
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 0
The QUiLoader class provides a form loader object to construct the user
interface. This user interface can be retrieved from any QIODevice, e.g.,
a QFile object, to obtain a form stored in a project's resource file. The
QUiLoader::load() function constructs the form widget using the user
interface description contained in the file.
The QtUiTools module classes can be included using the following directive:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 1
The QUiLoader::load() function is invoked as shown in this code from the
\l{Text Finder Example}{Text Finder} example:
\snippet examples/uitools/textfinder/textfinder.cpp 4
In a class that uses QtUiTools to build its user interface at run time, we
can locate objects in the form using qFindChild(). For example, in the
follownig code, we locate some components based on their object names and
widget types:
\snippet examples/uitools/textfinder/textfinder.cpp 1
Processing forms at run-time gives the developer the freedom to change a
program's user interface, just by changing the UI file. This is useful
when customizing programs to suit various user needs, such as extra large
icons or a different colour scheme for accessibility support.
\section1 Automatic Connections
The signals and slots connections defined for compile time or run time
forms can either be set up manually or automatically, using QMetaObject's
ability to make connections between signals and suitably-named slots.
Generally, in a QDialog, if we want to process the information entered by
the user before accepting it, we need to connect the clicked() signal from
the \gui OK button to a custom slot in our dialog. We will first show an
example of the dialog in which the slot is connected by hand then compare
it with a dialog that uses automatic connection.
\section2 A Dialog Without Auto-Connect
We define the dialog in the same way as before, but now include a slot in
addition to the constructor:
\snippet doc/src/snippets/designer/noautoconnection/imagedialog.h 0
The \c checkValues() slot will be used to validate the values provided by
the user.
In the dialog's constructor we set up the widgets as before, and connect
the \gui Cancel button's \l{QPushButton::clicked()}{clicked()} signal to
the dialog's reject() slot. We also disable the
\l{QPushButton::autoDefault}{autoDefault} property in both buttons to
ensure that the dialog does not interfere with the way that the line edit
handles return key events:
\snippet doc/src/snippets/designer/noautoconnection/imagedialog.cpp 0
\dots
\snippet doc/src/snippets/designer/noautoconnection/imagedialog.cpp 1
We connect the \gui OK button's \l{QPushButton::clicked()}{clicked()}
signal to the dialog's checkValues() slot which we implement as follows:
\snippet doc/src/snippets/designer/noautoconnection/imagedialog.cpp 2
This custom slot does the minimum necessary to ensure that the data
entered by the user is valid - it only accepts the input if a name was
given for the image.
\section2 Widgets and Dialogs with Auto-Connect
Although it is easy to implement a custom slot in the dialog and connect
it in the constructor, we could instead use QMetaObject's auto-connection
facilities to connect the \gui OK button's clicked() signal to a slot in
our subclass. \c{uic} automatically generates code in the dialog's
\c setupUi() function to do this, so we only need to declare and
implement a slot with a name that follows a standard convention:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 2
Using this convention, we can define and implement a slot that responds to
mouse clicks on the \gui OK button:
\snippet doc/src/snippets/designer/autoconnection/imagedialog.h 0
Another example of automatic signal and slot connection would be the
\l{Text Finder Example}{Text Finder} with its \c{on_findButton_clicked()}
slot.
We use QMetaObject's system to enable signal and slot connections:
\snippet examples/uitools/textfinder/textfinder.cpp 2
This enables us to implement the slot, as shown below:
\snippet examples/uitools/textfinder/textfinder.cpp 6
\dots
\snippet examples/uitools/textfinder/textfinder.cpp 8
Automatic connection of signals and slots provides both a standard naming
convention and an explicit interface for widget designers to work to. By
providing source code that implements a given interface, user interface
designers can check that their designs actually work without having to
write code themselves.
*/
/*!
\page designer-customizing-forms.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Using Stylesheets with Qt Designer
\nextpage Using Custom Widgets with Qt Designer
\title Customizing Qt Designer Forms
\image designer-form-settings.png
When saving a form in \QD, it is stored as a UI file. Several form
settings, for example the grid settings or the margin and spacing for the
default layout, are stored along with the form's components. These settings
are used when the \l uic generates the form's C++ code. For more
information on how to use forms in your application, see the
\l{Using a Designer UI File in Your Application} section.
\section1 Modifying the Form Settings
To modify the form settings, open the \gui Form menu and select \gui{Form
Settings...}
In the forms settings dialog you can specify the \gui Author of the form.
You can also alter the margin and spacing properties for the form's default
layout (\gui {Layout Default}). These default layout properties will be
replaced by the corresponding \gui {Layout Function}, if the function is
specified, when \c uic generates code for the form. The form settings
dialog lets you specify functions for both the margin and the spacing.
\target LayoutFunction
\table
\row
\i \inlineimage designer-form-layoutfunction.png
\i \bold{Layout Function}
The default layout properties will be replaced by the corresponding
\gui{Layout Function}, when \c uic generates code for the form. This is
useful when different environments requires different layouts for the same
form.
To specify layout functions for the form's margin and spacing, check the
\gui{Layout Function} group box to enable the line edits.
\endtable
You can also specify the form's \gui{Include Hints}; i.e., provide a list
of the header files which will then be included in the form window's
associated UI file. Header files may be local, i.e., relative to the
project's directory, \c "mywidget.h", or global, i.e. part of Qt or the
compilers standard libraries: \c .
Finally, you can specify the function used to load pixmaps into the form
window (the \gui {Pixmap Function}).
*/
/*!
\page designer-using-custom-widgets.html
\contentspage {Qt Designer Manual}{Contents}
\previouspage Customizing Qt Designer Forms
\nextpage Creating Custom Widgets for Qt Designer
\title Using Custom Widgets with Qt Designer
\QD can display custom widgets through its extensible plugin mechanism,
allowing the range of designable widgets to be extended by the user and
third parties. This feature also allows \QD to optionally support
\l{Qt3Support}{Qt 3 compatibility widgets}. Alternatively, it is possible
to use existing widgets as placeholders for widget classes that provide
similar APIs.
Widgets from the Qt3Support library are made available via in \QD's support
for custom widgets.
\section1 Handling Custom Widgets
Although \QD supports all of the standard Qt widgets, and can be configured
to handle widgets supplied in the Qt3Support library, some specialized
widgets may not be available as standard for a number of reasons:
\list
\i Custom widgets may not be available at the time the user interface
is being designed.
\i Custom widgets may be platform-specific, and designers may be
developing the user interface on a different platform to end users.
\i The source code for a custom widget is not available, or the user
interface designers are unable to use the widget for non-technical
reasons.
\endlist
In the above situations, it is still possible to design forms with the aim
of using custom widgets in the application. To achieve this, we can use
the widget promotion feature of \QD.
In all other cases, where the source code to the custom widgets is
available, we can adapt the custom widget for use with \QD.
\section2 Promoting Widgets
\image designer-promoting-widgets.png
If some forms must be designed, but certain custom widgets are unavailble
to the designer, we can substitute similar widgets to represent the missing
widgets. For example, we might represent instances of a custom push button
class, \c MyPushButton, with instances of QPushButton and promote these to
\c MyPushButton so that \l{uic.html}{uic} generates suitable code for this
missing class.
When choosing a widget to use as a placeholder, it is useful to compare the
API of the missing widget with those of standard Qt widgets. For
specialized widgets that subclass standard classes, the obvious choice of
placeholder is the base class of the custom widget; for example, QSlider
might be used for specialized QSlider subclasses.
For specialized widgets that do not share a common API with standard Qt
widgets, it is worth considering adapting a custom widget for use in \QD.
If this is not possible then QWidget is the obvious choice for a
placeholder widget since it is the lowest common denominator for all
widgets.
To add a placeholder, select an object of a suitable base class and choose
\gui{Promote to ...} from the form's context menu. After entering the class
name and header file in the lower part of the dialog, choose \gui{Add}. The
placeholder class will now appear along with the base class in the upper
list. Click the \gui{Promote} button to accept this choice.
Now, when the form's context menu is opened over objects of the base class,
the placeholder class will appear in the \gui{Promote to} submenu, allowing
for convenient promotion of objects to that class.
A promoted widget can be reverted to its base class by choosing
\gui{Demote to} from the form's context menu.
\section2 User Defined Custom Widgets
\image worldtimeclockplugin-example.png
Custom widgets can be adapted for use with \QD, giving designers the
opportunity to configure the user interface using the actual widgets that
will be used in an application rather than placeholder widgets. The process
of creating a custom widget plugin is described in the
\l{Creating Custom Widgets for Qt Designer} chapter of this manual.
To use a plugin created in this way, it is necessary to ensure that the
plugin is located on a path that \QD searches for plugins. Generally,
plugins stored in \c{$QTDIR/plugins/designer} will be loaded when \QD
starts. Further information on building and installing plugins can be found
\l{Creating Custom Widgets for Qt Designer#BuildingandInstallingthePlugin}
{here}. You can also refer to the \l{How to Create Qt Plugins}
{Plugins HOWTO} document for information about creating plugins.
*/
/*!
\page designer-creating-custom-widgets.html
\previouspage Using Custom Widgets with Qt Designer
\contentspage {Qt Designer Manual}{Contents}
\nextpage Creating Custom Widget Extensions
\title Creating Custom Widgets for Qt Designer
\QD's plugin-based architecture allows user-defined and third party custom
widgets to be edited just like you do with standard Qt widgets. All of the
custom widget's features are made available to \QD, including widget
properties, signals, and slots. Since \QD uses real widgets during the form
design process, custom widgets will appear the same as they do when
previewed.
\image worldtimeclockplugin-example.png
The \l QtDesigner module provides you with the ability to create custom
widgets in \QD.
\section1 Getting Started
To integrate a custom widget with \QD, you require a suitable description
for the widget and an appropriate \c{.pro} file.
\section2 Providing an Interface Description
To inform \QD about the type of widget you want to provide, create a
subclass of QDesignerCustomWidgetInterface that describes the various
properties your widget exposes. Most of these are supplied by functions
that are pure virtual in the base class, because only the author of the
plugin can provide this information.
\table
\header
\o Function
\o Description of the return value
\row
\o \c name()
\o The name of the class that provides the widget.
\row
\o \c group()
\o The group in \QD's widget box that the widget belongs to.
\row
\o \c toolTip()
\o A short description to help users identify the widget in \QD.
\row
\o \c whatsThis()
\o A longer description of the widget for users of \QD.
\row
\o \c includeFile()
\o The header file that must be included in applications that use
this widget. This information is stored in UI files and will
be used by \c uic to create a suitable \c{#includes} statement
in the code it generates for the form containing the custom
widget.
\row
\o \c icon()
\o An icon that can be used to represent the widget in \QD's
widget box.
\row
\o \c isContainer()
\o True if the widget will be used to hold child widgets;
false otherwise.
\row
\o \c createWidget()
\o A QWidget pointer to an instance of the custom widget,
constructed with the parent supplied.
\note createWidget() is a factory function responsible for
creating the widget only. The custom widget's properties will
not be available until load() returns.
\row
\o \c domXml()
\o A description of the widget's properties, such as its object
name, size hint, and other standard QWidget properties.
\row
\o \c codeTemplate()
\o This function is reserved for future use by \QD.
\endtable
Two other virtual functions can also be reimplemented:
\table
\row
\o \c initialize()
\o Sets up extensions and other features for custom widgets. Custom
container extensions (see QDesignerContainerExtension) and task
menu extensions (see QDesignerTaskMenuExtension) should be set
up in this function.
\row
\o \c isInitialized()
\o Returns true if the widget has been initialized; returns false
otherwise. Reimplementations usually check whether the
\c initialize() function has been called and return the result
of this test.
\endtable
\section2 Notes on the \c{domXml()} Function
The \c{domXml()} function returns a UI file snippet that is used by
\QD's widget factory to create a custom widget and its applicable
properties.
Since Qt 4.4, \QD's widget box allows for a complete UI file to
describe \bold one custom widget. The UI file can be loaded using the
\c{} tag. Specifying the tag allows for adding the
element that contains additional information for custom widgets. The
\c{} tag is sufficient if no additional information is required
If the custom widget does not provide a reasonable size hint, it is
necessary to specify a default geometry in the string returned by the
\c domXml() function in your subclass. For example, the
\c AnalogClockPlugin provided by the \l{designer/customwidgetplugin}
{Custom Widget Plugin} example, defines a default widgetgeometry in the
following way:
\dots
\snippet examples/designer/customwidgetplugin/customwidgetplugin.cpp 11
\dots
An additional feature of the \c domXml() function is that, if it returns
an empty string, the widget will not be installed in \QD's widget box.
However, it can still be used by other widgets in the form. This feature
is used to hide widgets that should not be explicitly created by the user,
but are required by other widgets.
A complete custom widget specification looks like:
\code
displayname="MyWidget">
widgets::MyWidget
addPage
\endcode
Attributes of the \c{} tag:
\table
\header
\o Attribute
\o Presence
\o Values
\o Comment
\row
\o \c{language}
\o optional
\o "c++", "jambi"
\o This attribute specifies the language the custom widget is intended for.
It is mainly there to prevent C++-plugins from appearing in Qt Jambi.
\row
\o \c{displayname}
\o optional
\o Class name
\o The value of the attribute appears in the Widget box and can be used to
strip away namespaces.
\endtable
The \c{} tag tells \QD and \l uic which method should be used to
add pages to a container widget. This applies to container widgets that require
calling a particular method to add a child rather than adding the child by passing
the parent. In particular, this is relevant for containers that are not a
a subclass of the containers provided in \QD, but are based on the notion
of \e{Current Page}. In addition, you need to provide a container extension
for them.
The \c{} element can contain a list of property meta information.
Currently, properties of type string are supported. For these properties, the
\c{} tag can be used. This tag has the following attributes:
\table
\header
\o Attribute
\o Presence
\o Values
\o Comment
\row
\o \c{name}
\o required
\o Name of the property
\row
\o \c{type}
\o required
\o See below table
\o The value of the attribute determines how the property editor will handle them.
\row
\o \c{notr}
\o optional
\o "true", "false"
\o If the attribute is "true", the value is not meant to be translated.
\endtable
Values of the \c{type} attribute of the string property:
\table
\header
\o Value
\o Type
\row
\o \c{"richtext"}
\o Rich text.
\row
\o \c{"multiline"}
\o Multi-line plain text.
\row
\o \c{"singleline"}
\o Single-line plain text.
\row
\o \c{"stylesheet"}
\o A CSS-style sheet.
\row
\o \c{"objectname"}
\o An object name (restricted set of valid characters).
\row
\o \c{"url"}
\o URL, file name.
\endtable
\section1 Plugin Requirements
In order for plugins to work correctly on all platforms, you need to ensure
that they export the symbols needed by \QD.
First of all, the plugin class must be exported in order for the plugin to
be loaded by \QD. Use the Q_EXPORT_PLUGIN2() macro to do this. Also, the
QDESIGNER_WIDGET_EXPORT macro must be used to define each custom widget class
within a plugin, that \QD will instantiate.
\section1 Creating Well Behaved Widgets
Some custom widgets have special user interface features that may make them
behave differently to many of the standard widgets found in \QD.
Specifically, if a custom widget grabs the keyboard as a result of a call
to QWidget::grabKeyboard(), the operation of \QD will be affected.
To give custom widgets special behavior in \QD, provide an implementation
of the initialize() function to configure the widget construction process
for \QD specific behavior. This function will be called for the first time
before any calls to createWidget() and could perhaps set an internal flag
that can be tested later when \QD calls the plugin's createWidget()
function.
\target BuildingandInstallingthePlugin
\section1 Building and Installing the Plugin
\section2 A Simple Plugin
The \l{Custom Widget Plugin Example} demonstrates a simple \QD plugin.
The \c{.pro} file for a plugin must specify the headers and sources for
both the custom widget and the plugin interface. Typically, this file only
has to specify that the plugin's project is to be built as a library, but
with specific plugin support for \QD. This is done with the following
declarations:
\snippet examples/designer/customwidgetplugin/customwidgetplugin.pro 1
If Qt is configured to build in both debug and release modes, \QD will be
built in release mode. When this occurs, it is necessary to ensure that
plugins are also built in release mode. To do this, include the following
declaration in the plugin's \c{.pro} file:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 3
If plugins are built in a mode that is incompatible with \QD, they will
not be loaded and installed. For more information about plugins, see the
\l{plugins-howto.html}{Plugins HOWTO} document.
It is also necessary to ensure that the plugin is installed together with
other \QD widget plugins:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 4
The \c $[QT_INSTALL_PLUGINS] variable is a placeholder to the location of
the installed Qt plugins. You can configure \QD to look for plugins in
other locations by setting the \c QT_PLUGIN_PATH environment variable
before running the application.
\note \QD will look for a \c designer subdirectory in each path supplied.
See QCoreApplication::libraryPaths() for more information about customizing
paths for libraries and plugins with Qt applications.
\section2 Splitting up the Plugin
In a real world scenario, you do not want to have dependencies of the
application making use of the custom widgets to the \QD headers and
libraries as introduced by the simple approach explained above.
There are two ways to resolve this:
\list
\i Create a \c{.pri} file that contains the headers sources and sources
of the custom widget:
\code
INCLUDEPATH += $$PWD
HEADERS += $$PWD/analogclock.h
SOURCES += $$PWD/analogclock.cpp
\endcode
This file would then be included by the \c{.pro} file of the plugin and
the application:
\code
include(customwidget.pri)
\endcode
Running \c{qmake -Wall} on the \c{.pro} files causes a warning to be
printed if an included \c{.pri} file cannot be found.
\i Create a standalone shared library containing the custom widgets only
as described in
\l{sharedlibrary.html}{Creating Shared Libraries}.
This library would then be used by the application as well as by the
\QD plugin. Care must be taken to ensure that the plugin can locate
the library at run-time.
\endlist
\section1 Related Examples
For more information on using custom widgets in \QD, refer to the
\l{designer/customwidgetplugin}{Custom Widget Plugin} and
\l{designer/worldtimeclockplugin}{World Time Clock Plugin} examples for more
information about using custom widgets in \QD. Also, you can use the
QDesignerCustomWidgetCollectionInterface class to combine several custom
widgets into a single library.
*/
/*!
\page designer-creating-custom-widgets-extensions.html
\previouspage Creating Custom Widgets for Qt Designer
\nextpage Qt Designer's UI File Format
\contentspage {Qt Designer Manual}{Contents}
\title Creating Custom Widget Extensions
Once you have a custom widget plugin for \QD, you can provide it with the
expected behavior and functionality within \QD's workspace, using custom
widget extensions.
\section1 Extension Types
There are several available types of extensions in \QD. You can use all of
these extensions in the same pattern, only replacing the respective
extension base class.
QDesignerContainerExtension is necessary when implementing a custom
multi-page container.
\table
\row
\i \inlineimage designer-manual-taskmenuextension.png
\i \bold{QDesignerTaskMenuExtension}
QDesignerTaskMenuExtension is useful for custom widgets. It provides an
extension that allows you to add custom menu entries to \QD's task
menu.
The \l{designer/taskmenuextension}{Task Menu Extension} example
illustrates how to use this class.
\row
\i \inlineimage designer-manual-containerextension.png
\i \bold{QDesignerContainerExtension}
QDesignerContainerExtension is necessary when implementing a custom
multi-page container. It provides an extension that allows you to add
and delete pages for a multi-page container plugin in \QD.
The \l{designer/containerextension}{Container Extension} example
further explains how to use this class.
\note It is not possible to add custom per-page properties for some
widgets (e.g., QTabWidget) due to the way they are implemented.
\endtable
\table
\row
\i \inlineimage designer-manual-membersheetextension.png
\i \bold{QDesignerMemberSheetExtension}
The QDesignerMemberSheetExtension class allows you to manipulate a
widget's member functions displayed when connecting signals and slots.
\row
\i \inlineimage designer-manual-propertysheetextension.png
\i \bold{QDesignerPropertySheetExtension,
QDesignerDynamicPropertySheetExtension}
These extension classes allow you to control how a widget's properties
are displayed in \QD's property editor.
\endtable
\omit
\row
\o
\o \bold {QDesignerScriptExtension}
The QDesignerScriptExtension class allows you to define script
snippets that are executed when a form is loaded. The extension
is primarily intended to be used to set up the internal states
of custom widgets.
\endtable
\endomit
\QD uses the QDesignerPropertySheetExtension and the
QDesignerMemberSheetExtension classes to feed its property and signal and
slot editors. Whenever a widget is selected in its workspace, \QD will
query for the widget's property sheet extension; likewise, whenever a
connection between two widgets is requested, \QD will query for the
widgets' member sheet extensions.
\warning All widgets have default property and member sheets. If you
implement custom property sheet or member sheet extensions, your custom
extensions will override the default sheets.
\section1 Creating an Extension
To create an extension you must inherit both QObject and the appropriate
base class, and reimplement its functions. Since we are implementing an
interface, we must ensure that it is made known to the meta object system
using the Q_INTERFACES() macro in the extension class's definition. For
example:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 7
This enables \QD to use the qobject_cast() function to query for supported
interfaces using a QObject pointer only.
\section1 Exposing an Extension to Qt Designer
In \QD the extensions are not created until they are required. For this
reason, when implementing extensions, you must subclass QExtensionFactory
to create a class that is able to make instances of your extensions. Also,
you must register your factory with \QD's extension manager; the extension
manager handles the construction of extensions.
When an extension is requested, \QD's extension manager will run through
its registered factories calling QExtensionFactory::createExtension() for
each of them until it finds one that is able to create the requested
extension for the selected widget. This factory will then make an instance
of the extension.
\image qtdesignerextensions.png
\section2 Creating an Extension Factory
The QExtensionFactory class provides a standard extension factory, but it
can also be used as an interface for custom extension factories.
The purpose is to reimplement the QExtensionFactory::createExtension()
function, making it able to create your extension, such as a
\l{designer/containerextension}{MultiPageWidget} container extension.
You can either create a new QExtensionFactory and reimplement the
QExtensionFactory::createExtension() function:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 8
or you can use an existing factory, expanding the
QExtensionFactory::createExtension() function to enable the factory to
create your custom extension as well:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 9
\section2 Accessing Qt Designer's Extension Manager
When implementing a custom widget plugin, you must subclass the
QDesignerCustomWidgetInterface to expose your plugin to \QD. This is
covered in more detail in the
\l{Creating Custom Widgets for Qt Designer} section. The registration of
an extension factory is typically made in the
QDesignerCustomWidgetInterface::initialize() function:
\snippet doc/src/snippets/code/doc_src_designer-manual.qdoc 10
The \c formEditor parameter in the
QDesignerCustomWidgetInterface::initialize() function is a pointer to \QD's
current QDesignerFormEditorInterface object. You must use the
QDesignerFormEditorInterface::extensionManager() function to retrieve an
interface to \QD's extension manager. Then you use the
QExtensionManager::registerExtensions() function to register your custom
extension factory.
\section1 Related Examples
For more information on creating custom widget extensions in \QD, refer to
the \l{designer/taskmenuextension}{Task Menu Extension} and
\l{designer/containerextension}{Container Extension} examples.
*/
/*!
\page designer-ui-file-format.html
\previouspage Creating Custom Widget Extensions
\contentspage {Qt Designer Manual}{Contents}
\title Qt Designer's UI File Format
The \c UI file format used by \QD is described by the
\l{http://www.w3.org/XML/Schema}{XML schema} presented below,
which we include for your convenience. Be aware that the format
may change in future Qt releases.
\quotefile tools/designer/data/ui4.xsd
*/
/*!
\page designer-recursive-shadow-casting.html
\title Implementation of the Recursive Shadow Casting Algorithm in Qt Designer
\contentspage {Qt Designer Manual}{Contents}
\ingroup licensing
\brief License information for contributions to specific parts of the Qt
Designer source code.
\legalese
Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). \BR
Copyright (C) 2005 Bjoern Bergstroem
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, modify, market, reproduce,
grant sublicenses and distribute subject to the following conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software. These
files are provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
WARRANTY OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
PURPOSE.
\endlegalese
*/