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diff --git a/doc/src/examples/spinboxes.qdoc b/doc/src/examples/spinboxes.qdoc new file mode 100644 index 0000000..d8b0daa --- /dev/null +++ b/doc/src/examples/spinboxes.qdoc @@ -0,0 +1,205 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the documentation of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3.0 as published by the Free Software +** Foundation and appearing in the file LICENSE.GPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU General Public License version 3.0 requirements will be +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +/*! + \example widgets/spinboxes + \title Spin Boxes Example + + The Spin Boxes example shows how to use the many different types of spin boxes + available in Qt, from a simple QSpinBox widget to more complex editors like + the QDateTimeEdit widget. + + \image spinboxes-example.png + + The example consists of a single \c Window class that is used to display the + different spin box-based widgets available with Qt. + + \section1 Window Class Definition + + The \c Window class inherits QWidget and contains two slots that are used + to provide interactive features: + + \snippet examples/widgets/spinboxes/window.h 0 + + The private functions are used to set up each type of spin box in the window. + We use member variables to keep track of various widgets so that they can + be reconfigured when required. + + \section1 Window Class Implementation + + The constructor simply calls private functions to set up the different types + of spin box used in the example, and places each group in a layout: + + \snippet examples/widgets/spinboxes/window.cpp 0 + + We use the layout to manage the arrangement of the window's child widgets, + and change the window title. + + The \c createSpinBoxes() function constructs a QGroupBox and places three + QSpinBox widgets inside it with descriptive labels to indicate the types of + input they expect. + + \snippet examples/widgets/spinboxes/window.cpp 1 + + The first spin box shows the simplest way to use QSpinBox. It accepts values + from -20 to 20, the current value can be increased or decreased by 1 with + either the arrow buttons or \key{Up} and \key{Down} keys, and the default + value is 0. + + The second spin box uses a larger step size and displays a suffix to + provide more information about the type of data the number represents: + + \snippet examples/widgets/spinboxes/window.cpp 2 + + This spin box also displays a + \l{QAbstractSpinBox::specialValueText}{special value} instead of the minimum + value defined for it. This means that it will never show \gui{0%}, but will + display \gui{Automatic} when the minimum value is selected. + + The third spin box shows how a prefix can be used: + + \snippet examples/widgets/spinboxes/window.cpp 4 + + For simplicity, we show a spin box with a prefix and no suffix. It is also + possible to use both at the same time. + + \snippet examples/widgets/spinboxes/window.cpp 5 + + The rest of the function sets up a layout for the group box and places each + of the widgets inside it. + + The \c createDateTimeEdits() function constructs another group box with a + selection of spin boxes used for editing dates and times. + + \snippet examples/widgets/spinboxes/window.cpp 6 + + The first spin box is a QDateEdit widget that is able to accept dates + within a given range specified using QDate values. The arrow buttons and + \key{Up} and \key{Down} keys can be used to increase and decrease the + values for year, month, and day when the cursor is in the relevant section. + + The second spin box is a QTimeEdit widget: + + \snippet examples/widgets/spinboxes/window.cpp 7 + + Acceptable values for the time are defined using QTime values. + + The third spin box is a QDateTimeEdit widget that can display both date and + time values, and we place a label above it to indicate the range of allowed + times for a meeting. These widgets will be updated when the user changes a + format string. + + \snippet examples/widgets/spinboxes/window.cpp 8 + + The format string used for the date time editor, which is also shown in the + string displayed by the label, is chosen from a set of strings in a combobox: + + \snippet examples/widgets/spinboxes/window.cpp 9 + \codeline + \snippet examples/widgets/spinboxes/window.cpp 10 + + A signal from this combobox is connected to a slot in the \c Window class + (shown later). + + \snippet examples/widgets/spinboxes/window.cpp 11 + + Each child widget of the group box in placed in a layout. + + The \c setFormatString() slot is called whenever the user selects a new + format string in the combobox. The display format for the QDateTimeEdit + widget is set using the raw string passed by the signal: + + \snippet examples/widgets/spinboxes/window.cpp 12 + + Depending on the visible sections in the widget, we set a new date or time + range, and update the associated label to provide relevant information for + the user: + + \snippet examples/widgets/spinboxes/window.cpp 13 + + When the format string is changed, there will be an appropriate label and + entry widget for dates, times, or both types of input. + + The \c createDoubleSpinBoxes() function constructs three spin boxes that are + used to input double-precision floating point numbers: + + \snippet examples/widgets/spinboxes/window.cpp 14 + + Before the QDoubleSpinBox widgets are constructed, we create a spin box to + control how many decimal places they show. By default, only two decimal places + are shown in the following spin boxes, each of which is the equivalent of a + spin box in the group created by the \c createSpinBoxes() function. + + The first double spin box shows a basic double-precision spin box with the + same range, step size, and default value as the first spin box in the + \c createSpinBoxes() function: + + \snippet examples/widgets/spinboxes/window.cpp 15 + + However, this spin box also allows non-integer values to be entered. + + The second spin box displays a suffix and shows a special value instead + of the minimum value: + + \snippet examples/widgets/spinboxes/window.cpp 16 + + The third spin box displays a prefix instead of a suffix: + + \snippet examples/widgets/spinboxes/window.cpp 17 + + We connect the QSpinBox widget that specifies the precision to a slot in + the \c Window class. + + \snippet examples/widgets/spinboxes/window.cpp 18 + + The rest of the function places each of the widgets into a layout for the + group box. + + The \c changePrecision() slot is called when the user changes the value in + the precision spin box: + + \snippet examples/widgets/spinboxes/window.cpp 19 + + This function simply uses the integer supplied by the signal to specify the + number of decimal places in each of the QDoubleSpinBox widgets. Each one + of these will be updated automatically when their + \l{QDoubleSpinBox::decimals}{decimals} property is changed. +*/ |