aboutsummaryrefslogtreecommitdiffstats
path: root/doc/src/declarative/qdeclarativedocument.qdoc
diff options
context:
space:
mode:
authorQt by Nokia <qt-info@nokia.com>2011-04-27 12:05:43 +0200
committeraxis <qt-info@nokia.com>2011-04-27 12:05:43 +0200
commit885735d011472bcfbb96e688d9e64553d7fe9d4b (patch)
tree734963625eba643bf11bc4870a4c407809a6400a /doc/src/declarative/qdeclarativedocument.qdoc
Initial import from the monolithic Qt.
This is the beginning of revision history for this module. If you want to look at revision history older than this, please refer to the Qt Git wiki for how to use Git history grafting. At the time of writing, this wiki is located here: http://qt.gitorious.org/qt/pages/GitIntroductionWithQt If you have already performed the grafting and you don't see any history beyond this commit, try running "git log" with the "--follow" argument. Branched from the monolithic repo, Qt master branch, at commit 896db169ea224deb96c59ce8af800d019de63f12
Diffstat (limited to 'doc/src/declarative/qdeclarativedocument.qdoc')
-rw-r--r--doc/src/declarative/qdeclarativedocument.qdoc143
1 files changed, 143 insertions, 0 deletions
diff --git a/doc/src/declarative/qdeclarativedocument.qdoc b/doc/src/declarative/qdeclarativedocument.qdoc
new file mode 100644
index 0000000000..423d77c775
--- /dev/null
+++ b/doc/src/declarative/qdeclarativedocument.qdoc
@@ -0,0 +1,143 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 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.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** 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 Free Documentation License
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of this
+** file.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+\page qdeclarativedocuments.html
+\title QML Documents
+\brief A description of QML documents and the kind of content they contain.
+
+A QML document is a block of QML source code. QML documents generally correspond to files
+stored on a disk or at a location on a network, but they can also be constructed directly
+from text data.
+
+Here is a simple QML document:
+
+\snippet doc/src/snippets/declarative/qml-documents/non-trivial.qml document
+
+QML documents are always encoded in UTF-8 format.
+
+A QML document always begins with one or more import statements. To prevent elements
+introduced in later versions from affecting existing QML programs, the element types
+available within a document are controlled by the imported QML \l {Modules}. That is,
+QML is a \e versioned language.
+
+Syntactically a QML document is self contained; QML does \e not have a preprocessor that
+modifies the document prior to presentation to the QML runtime. \c import statements
+do not "include" code in the document, but instead instruct the QML runtime on how to
+resolve type references found in the document. Any type reference present in a QML
+document - such as \c Rectangle and \c ListView - including those made within an
+\l {Inline JavaScript}{JavaScript block} or \l {Property Binding}s, are \e resolved based exclusively on the
+import statements. QML does not import any modules by default, so at least one \c import
+statement must be present or no elements will be available!
+
+Each \c id value in a QML document must be unique within that document. They
+do not need to be unique across different documents as id values are
+resolved according to the document scope.
+
+
+\section1 Documents as Component Definitions
+
+A QML document defines a single, top-level \l {QDeclarativeComponent}{QML component}. A QML component
+is a template that is interpreted by the QML runtime to create an object with some predefined
+behaviour. As it is a template, a single QML component can be "run" multiple times to
+produce several objects, each of which are said to be \e instances of the component.
+
+Once created, instances are not dependent on the component that created them, so they can
+operate on independent data. Here is an example of a simple "Button" component (defined
+in a \c Button.qml file) that is instantiated four times by \c application.qml.
+Each instance is created with a different value for its \c text property:
+
+\table
+\row
+\o Button.qml
+\o application.qml
+
+\row
+\o \snippet doc/src/snippets/declarative/qml-documents/qmldocuments.qml document
+\o
+\qml
+import QtQuick 1.0
+
+Column {
+ spacing: 10
+
+ Button { text: "Apple" }
+ Button { text: "Orange" }
+ Button { text: "Pear" }
+ Button { text: "Grape" }
+}
+\endqml
+
+\image anatomy-component.png
+
+\endtable
+
+Any snippet of QML code can become a component, just by placing it in the file "<Name>.qml"
+where <Name> is the new element name, and begins with an \bold uppercase letter. Note that
+the case of all characters in the <Name> are significant on some filesystems, notably
+UNIX filesystems. It is recommended that the case of the filename matches the case of
+the component name in QML exactly, regardless of the platform the QML will be deployed to.
+
+These QML component files automatically become available as new QML element types
+to other QML components and applications in the same directory.
+
+
+
+\section1 Inline Components
+
+In addition to the top-level component that all QML documents define, and any reusable
+components placed in separate files, documents may also
+include \e inline components. Inline components are declared using the
+\l Component element, as can be seen in the first example above. Inline components share
+all the characteristics of regular top-level components and use the same \c import list as their
+containing QML document. Components are one of the most basic building blocks in QML, and are
+frequently used as "factories" by other elements. For example, the \l ListView element uses the
+\c delegate component as the template for instantiating list items - each list item is just a
+new instance of the component with the item specific data set appropriately.
+
+Like other \l {QML Elements}, the \l Component element is an object and must be assigned to a
+property. \l Component objects may also have an object id. In the first example on this page,
+the inline component is added to the \l Rectangle's \c resources list, and then
+\l {Property Binding} is used to assign the \l Component to the \l ListView's \c delegate
+property. While using property binding allows the \l Component object to be shared (for example,
+if the QML document contained multiple \l ListView's with the same delegate), in this case the
+\l Component could have been assigned directly to the \l ListView's \c delegate. The QML
+language even contains a syntactic optimization when assigning directly to a component property
+for this case where it will automatically insert the \l Component tag.
+
+These final two examples are behaviorally identical to the original document.
+
+\table
+\row
+\o
+\snippet doc/src/snippets/declarative/qml-documents/inline-component.qml document
+\o
+\snippet doc/src/snippets/declarative/qml-documents/inline-text-component.qml document
+\endtable
+
+\sa QDeclarativeComponent
+*/