summaryrefslogtreecommitdiffstats
path: root/doc/src
diff options
context:
space:
mode:
authorBea Lam <bea.lam@nokia.com>2010-04-12 04:45:51 (GMT)
committerBea Lam <bea.lam@nokia.com>2010-04-12 04:45:51 (GMT)
commit1e3b3551b8498e1f4dc92982e2a040ba90a6bf26 (patch)
treedee1f64c3a9e26e07bc9cea00b90e800b932a6f2 /doc/src
parent20a00436174faf746be14f5c36908710eeb44101 (diff)
parent381ea9c22eb8f6b3701376a650202f094e17746d (diff)
downloadQt-1e3b3551b8498e1f4dc92982e2a040ba90a6bf26.zip
Qt-1e3b3551b8498e1f4dc92982e2a040ba90a6bf26.tar.gz
Qt-1e3b3551b8498e1f4dc92982e2a040ba90a6bf26.tar.bz2
Merge branch '4.7' of scm.dev.nokia.troll.no:qt/qt-qml into 4.7
Conflicts: doc/src/declarative/javascriptblocks.qdoc
Diffstat (limited to 'doc/src')
-rw-r--r--doc/src/declarative/codingconventions.qdoc131
-rw-r--r--doc/src/declarative/declarativeui.qdoc9
-rw-r--r--doc/src/declarative/javascriptblocks.qdoc58
-rw-r--r--doc/src/snippets/declarative/codingconventions/dotproperties.qml28
-rw-r--r--doc/src/snippets/declarative/codingconventions/javascript-imports.qml7
-rw-r--r--doc/src/snippets/declarative/codingconventions/javascript.qml33
-rw-r--r--doc/src/snippets/declarative/codingconventions/lists.qml22
-rw-r--r--doc/src/snippets/declarative/codingconventions/myscript.js9
-rw-r--r--doc/src/snippets/declarative/codingconventions/photo.qml37
9 files changed, 301 insertions, 33 deletions
diff --git a/doc/src/declarative/codingconventions.qdoc b/doc/src/declarative/codingconventions.qdoc
new file mode 100644
index 0000000..e1e7871
--- /dev/null
+++ b/doc/src/declarative/codingconventions.qdoc
@@ -0,0 +1,131 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+\page codingconventions.html
+\title QML Coding Conventions
+
+This document contains the QML coding conventions that we follow in our documentation and examples and recommend that others follow.
+
+This page assumes that you are already familiar with the QML language.
+If you need an introduction to the language, please read \l {Introduction to the QML language}{the QML introduction} first.
+
+
+\section1 QML objects
+
+Through our documentation and examples, QML objects are always structured in the following order:
+
+\list
+\o id
+\o property declarations
+\o signal declarations
+\o javascript functions
+\o object properties
+\o child objects
+\o states
+\o transitions
+\endlist
+
+For better readability, we separate these different parts with an empty line.
+
+
+For example, a hypothetical \e photo QML object would look like this:
+
+\snippet doc/src/snippets/declarative/codingconventions/photo.qml 0
+
+
+\section1 Grouped properties
+
+If using multiple properties from a group of properties,
+we use the \e {group notation} rather than the \e {dot notation} to improve readability.
+
+For example, this:
+
+\snippet doc/src/snippets/declarative/codingconventions/dotproperties.qml 0
+
+can be written like this:
+
+\snippet doc/src/snippets/declarative/codingconventions/dotproperties.qml 1
+
+
+\section1 Lists
+
+If a list contains only one element, we generally omit the square brackets.
+
+For example, it is very common for a component to only have one state.
+
+In this case, instead of:
+
+\snippet doc/src/snippets/declarative/codingconventions/lists.qml 0
+
+we will write this:
+
+\snippet doc/src/snippets/declarative/codingconventions/lists.qml 1
+
+
+\section1 Javascript
+
+If the script is a single expression, we recommend writing it inline:
+
+\snippet doc/src/snippets/declarative/codingconventions/javascript.qml 0
+
+If the script is only a couple of lines long, we generally use a block:
+
+\snippet doc/src/snippets/declarative/codingconventions/javascript.qml 1
+
+If the script is more than a couple of lines long or can be used by different objects, we recommend creating a function and calling it like this:
+
+\snippet doc/src/snippets/declarative/codingconventions/javascript.qml 2
+
+For long scripts, we will put the functions in their own javascript file and import it like this:
+
+\snippet doc/src/snippets/declarative/codingconventions/javascript-imports.qml 0
+
+*/
+
+
+
+
+
+
+
+
+
diff --git a/doc/src/declarative/declarativeui.qdoc b/doc/src/declarative/declarativeui.qdoc
index f310484..a4f4bc7 100644
--- a/doc/src/declarative/declarativeui.qdoc
+++ b/doc/src/declarative/declarativeui.qdoc
@@ -47,10 +47,10 @@
highly dynamic, custom user interfaces.
Qt Declarative UI provides a declarative framework for building highly dynamic, custom
-user interfaces. Declarative UI helps programmers and designers collaborate to build
-the animation rich, fluid user interfaces that are becoming common in portable
-consumer devices, such as mobile phones, media players, set-top boxes and netbooks.
-The Qt Declarative module provides an engine for interpreting the declarative QML
+user interfaces. Declarative UI helps programmers and designers collaborate to build
+the animation rich, fluid user interfaces that are becoming common in portable
+consumer devices, such as mobile phones, media players, set-top boxes and netbooks.
+The Qt Declarative module provides an engine for interpreting the declarative QML
language, and a rich set of \l {QML Elements}{QML elements} that can be used
from QML.
@@ -106,5 +106,6 @@ completely new applications. QML is fully \l {Extending QML in C++}{extensible
\o \l {QML Security}
\o \l {QtDeclarative Module}
\o \l {Debugging QML}
+\o \l {QML Coding Conventions}
\endlist
*/
diff --git a/doc/src/declarative/javascriptblocks.qdoc b/doc/src/declarative/javascriptblocks.qdoc
index 5fc3938..8ffe58c 100644
--- a/doc/src/declarative/javascriptblocks.qdoc
+++ b/doc/src/declarative/javascriptblocks.qdoc
@@ -41,25 +41,25 @@
/*!
\page qdeclarativejavascript.html
-\title Integrating JavaScript
+\title Integrating JavaScript
-QML encourages building UIs declaratively, using \l {Property Binding} and the
+QML encourages building UIs declaratively, using \l {Property Binding} and the
composition of existing \l {QML Elements}. To allow the implementation of more
advanced behavior, QML integrates tightly with imperative JavaScript code.
The JavaScript environment provided by QML is stricter than that in a webbrowser.
In QML you cannot add, or modify, members of the JavaScript global object. It
is possible to do this accidentally by using a variable without declaring it. In
-QML this will throw an exception, so all local variables should be explicitly
+QML this will throw an exception, so all local variables should be explicitly
declared.
-In addition to the standard JavaScript properties, the \l {QML Global Object}
+In addition to the standard JavaScript properties, the \l {QML Global Object}
includes a number of helper methods that simplify building UIs and interacting
with the QML environment.
\section1 Inline JavaScript
-Small JavaScript functions can be written inline with other QML declarations.
+Small JavaScript functions can be written inline with other QML declarations.
These inline functions are added as methods to the QML element that contains
them.
@@ -73,14 +73,14 @@ Item {
return a * factorial(a - 1);
}
- MouseRegion {
+ MouseArea {
anchors.fill: parent
onClicked: print(factorial(10))
}
}
\endcode
-As methods, inline functions on the root element in a QML component can be
+As methods, inline functions on the root element in a QML component can be
invoked by callers outside the component. If this is not desired, the method
can be added to a non-root element or, preferably, written in an external
JavaScript file.
@@ -97,7 +97,7 @@ could be moved into an external file named \c factorial.js, and accessed like th
\code
import "factorial.js" as MathFunctions
Item {
- MouseRegion {
+ MouseArea {
anchors.fill: parent
onClicked: print(MathFunctions.factorial(10))
}
@@ -108,24 +108,24 @@ Both relative and absolute JavaScript URLs can be imported. In the case of a
relative URL, the location is resolved relative to the location of the
\l {QML Document} that contains the import. If the script file is not accessible,
an error will occur. If the JavaScript needs to be fetched from a network
-resource, the QML document stays in the
-\l {QDeclarativeComponent::status()}{"Loading" status} until the script has been
+resource, the QML document has a "Loading"
+\l {QDeclarativeComponent::status()}{status} until the script has been
downloaded.
-Imported JavaScript files are always qualified using the "as" keyword. The
+Imported JavaScript files are always qualified using the "as" keyword. The
qualifier for JavaScript files must be unique, so there is always a one-to-one
mapping between qualifiers and JavaScript files.
\section2 Code-Behind Implementation Files
-Most JavaScript files imported into a QML file are stateful, logic implementations
-for the QML file importing them. In these cases, for QML component instances to
-behave correctly each instance requires a separate copy of the JavaScript objects
+Most JavaScript files imported into a QML file are stateful, logic implementations
+for the QML file importing them. In these cases, for QML component instances to
+behave correctly each instance requires a separate copy of the JavaScript objects
and state.
The default behavior when importing JavaScript files is to provide a unique, isolated
-copy for each QML component instance. The code runs in the same scope as the QML
-component instance and consequently can can access and manipulate the objects and
+copy for each QML component instance. The code runs in the same scope as the QML
+component instance and consequently can can access and manipulate the objects and
properties declared.
\section2 Stateless JavaScript libraries
@@ -134,8 +134,8 @@ Some JavaScript files act more like libraries - they provide a set of stateless
helper functions that take input and compute output, but never manipulate QML
component instances directly.
-As it would be wasteful for each QML component instance to have a unique copy of
-these libraries, the JavaScript programmer can indicate a particular file is a
+As it would be wasteful for each QML component instance to have a unique copy of
+these libraries, the JavaScript programmer can indicate a particular file is a
stateless library through the use of a pragma, as shown in the following example.
\code
@@ -162,7 +162,7 @@ parameters.
It is occasionally necessary to run some imperative code at application (or
component instance) "startup". While it is tempting to just include the startup
script as \e {global code} in an external script file, this can have severe limitations
-as the QML environment may not have been fully established. For example, some objects
+as the QML environment may not have been fully established. For example, some objects
might not have been created or some \l {Property Binding}s may not have been run.
\l {QML JavaScript Restrictions} covers the exact limitations of global script code.
@@ -184,21 +184,21 @@ Any element in a QML file - including nested elements and nested QML component
instances - can use this attached property. If there is more than one \c onCompleted()
handler to execute at startup, they are run sequentially in an undefined order.
-\section1 QML JavaScript Restrictions
+\section1 QML JavaScript Restrictions
QML executes standard JavaScript code, with the following restrictions:
\list
\o JavaScript code cannot modify the global object.
-In QML, the global object is constant - existing properties cannot be modified or
+In QML, the global object is constant - existing properties cannot be modified or
deleted, and no new properties may be created.
-Most JavaScript programs do not intentionally modify the global object. However,
+Most JavaScript programs do not intentionally modify the global object. However,
JavaScript's automatic creation of undeclared variables is an implicit modification
of the global object, and is prohibited in QML.
-Assuming that the \c a variable does not exist in the scope chain, the following code
+Assuming that the \c a variable does not exist in the scope chain, the following code
is illegal in QML.
\code
@@ -216,18 +216,18 @@ for (var ii = 1; ii < 10; ++ii) a = a * ii;
console.log("Result: " + a);
\endcode
-Any attempt to modify the global object - either implicitly or explicitly - will
-cause an exception. If uncaught, this will result in an warning being printed,
+Any attempt to modify the global object - either implicitly or explicitly - will
+cause an exception. If uncaught, this will result in an warning being printed,
that includes the file and line number of the offending code.
\o Global code is run in a reduced scope
During startup, if a QML file includes an external JavaScript file with "global"
code, it is executed in a scope that contains only the external file itself and
-the global object. That is, it will not have access to the QML objects and
+the global object. That is, it will not have access to the QML objects and
properties it \l {QML Scope}{normally would}.
-Global code that only accesses script local variable is permitted. This is an
+Global code that only accesses script local variable is permitted. This is an
example of valid global code.
\code
@@ -241,8 +241,8 @@ Global code that accesses QML objects will not run correctly.
var initialPosition = { rootObject.x, rootObject.y }
\endcode
-This restriction exists as the QML environment is not yet fully established.
-To run code after the environment setup has completed, refer to
+This restriction exists as the QML environment is not yet fully established.
+To run code after the environment setup has completed, refer to
\l {Running JavaScript at Startup}.
\endlist
diff --git a/doc/src/snippets/declarative/codingconventions/dotproperties.qml b/doc/src/snippets/declarative/codingconventions/dotproperties.qml
new file mode 100644
index 0000000..211cac1
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/dotproperties.qml
@@ -0,0 +1,28 @@
+import Qt 4.6
+
+Item {
+
+//! [0]
+Rectangle {
+ anchors.left: parent.left; anchors.top: parent.top; anchors.right: parent.right; anchors.leftMargin: 20
+}
+
+Text {
+ text: "hello"
+ font.bold: true; font.italic: true; font.pixelSize: 20; font.capitalization: Font.AllUppercase
+}
+
+//! [0]
+
+//! [1]
+Rectangle {
+ anchors { left: parent.left; top: parent.top; right: parent.right; leftMargin: 20 }
+}
+
+Text {
+ text: "hello"
+ font { bold: true; italic: true; pixelSize: 20; capitalization: Font.AllUppercase }
+}
+//! [1]
+
+}
diff --git a/doc/src/snippets/declarative/codingconventions/javascript-imports.qml b/doc/src/snippets/declarative/codingconventions/javascript-imports.qml
new file mode 100644
index 0000000..a216e1c
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/javascript-imports.qml
@@ -0,0 +1,7 @@
+import Qt 4.6
+
+//![0]
+import "myscript.js" as Script
+
+Rectangle { color: "blue"; width: Script.calculateWidth(parent) }
+//![0]
diff --git a/doc/src/snippets/declarative/codingconventions/javascript.qml b/doc/src/snippets/declarative/codingconventions/javascript.qml
new file mode 100644
index 0000000..ccb299b
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/javascript.qml
@@ -0,0 +1,33 @@
+import Qt 4.6
+
+Rectangle {
+
+//![0]
+Rectangle { color: "blue"; width: parent.width / 3 }
+//![0]
+
+//![1]
+Rectangle {
+ color: "blue"
+ width: {
+ var w = parent.width / 3
+ console.debug(w)
+ return w
+ }
+}
+//![1]
+
+//![2]
+function calculateWidth(object)
+{
+ var w = object.width / 3
+ // ...
+ // more javascript code
+ // ...
+ console.debug(w)
+ return w
+}
+
+Rectangle { color: "blue"; width: calculateWidth(parent) }
+//![2]
+}
diff --git a/doc/src/snippets/declarative/codingconventions/lists.qml b/doc/src/snippets/declarative/codingconventions/lists.qml
new file mode 100644
index 0000000..b8cc8a3
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/lists.qml
@@ -0,0 +1,22 @@
+import Qt 4.6
+
+Item {
+ Item {
+//! [0]
+states: [
+ State {
+ name: "open"
+ PropertyChanges { target: container; width: 200 }
+ }
+]
+//! [0]
+ }
+ Item {
+//! [1]
+states: State {
+ name: "open"
+ PropertyChanges { target: container; width: 200 }
+}
+//! [1]
+ }
+}
diff --git a/doc/src/snippets/declarative/codingconventions/myscript.js b/doc/src/snippets/declarative/codingconventions/myscript.js
new file mode 100644
index 0000000..cfa6462
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/myscript.js
@@ -0,0 +1,9 @@
+function calculateWidth(parent)
+{
+ var w = parent.width / 3
+ // ...
+ // more javascript code
+ // ...
+ console.debug(w)
+ return w
+}
diff --git a/doc/src/snippets/declarative/codingconventions/photo.qml b/doc/src/snippets/declarative/codingconventions/photo.qml
new file mode 100644
index 0000000..3a59e1f
--- /dev/null
+++ b/doc/src/snippets/declarative/codingconventions/photo.qml
@@ -0,0 +1,37 @@
+import Qt 4.6
+
+//! [0]
+Rectangle {
+ id: photo // id on the first line makes it easy to find an object
+
+ property bool thumbnail: false // property declarations
+ property alias image: photoImage.source
+
+ signal clicked // signal declarations
+
+ function doSomething(x) { // javascript functions
+ return x + photoImage.width
+ }
+
+ x: 20; y: 20; width: 200; height: 150 // object properties
+ color: "gray" // try to group related properties together
+
+ Rectangle { // child objects
+ id: border
+ anchors.centerIn: parent; color: "white"
+
+ Image { id: photoImage; anchors.centerIn: parent }
+ }
+
+ states: State { // states
+ name: "selected"
+ PropertyChanges { target: border; color: "red" }
+ }
+
+ transitions: Transition { // transitions
+ from: ""; to: "selected"
+ ColorAnimation { target: border; duration: 200 }
+ }
+}
+//! [0]
+