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Diffstat (limited to 'src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc')
| -rw-r--r-- | src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc | 87 |
1 files changed, 2 insertions, 85 deletions
diff --git a/src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc b/src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc index 79bd3df9d9..a2397b6cfb 100644 --- a/src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc +++ b/src/qml/doc/src/qmllanguageref/modules/cppplugins.qdoc @@ -32,96 +32,13 @@ \section1 Creating a Plugin - The \l{QQmlEngine}{QML engine} load C++ plugins for QML. + The \l{QQmlEngine}{QML engine} loads C++ plugins for QML. Such plugins are usually provided in a QML extension module, and can provide types for use by clients in QML documents which import the module. A module requires at least one type registered in order to be considered valid. - QQmlExtensionPlugin is a plugin interface that makes it possible to - create QML extensions that can be loaded dynamically into QML applications. - These extensions allow custom QML types to be made available to the - QML engine. - - To write a QML extension plugin: - \list 1 - \li Subclass QQmlExtensionPlugin - \list - \li Use the Q_PLUGIN_METADATA() macro to register the plugin with - the Qt meta object system - \li Override the \l{QQmlExtensionPlugin::}{registerTypes()} method - and call qmlRegisterType() to register the types to be exported - by the plugin - \endlist - \li Write a project file for the plugin - \li Create a \l{Module Definition qmldir Files}{qmldir file} to - describe the plugin - \endlist - - QML extension plugins are for either application-specific or library-like - plugins. Library plugins should limit themselves to registering types, as - any manipulation of the engine's root context may cause conflicts or other - issues in the library user's code. - -\section1 Plugin Example - - Suppose there is a new \c TimeModel C++ class that should be made available - as a new QML type. It provides the current time through \c hour and \c minute - properties. - - \snippet qmlextensionplugins/plugin.cpp 0 - \dots - - To make this type available, we create a plugin class named \c QExampleQmlPlugin - which is a subclass of \l QQmlExtensionPlugin. It overrides the - \l{QQmlExtensionPlugin::}{registerTypes()} method in order to register the \c TimeModel - type using qmlRegisterType(). It also uses the Q_PLUGIN_METADATA() macro in the class - definition to register the plugin with the Qt meta object system using a unique - identifier for the plugin. - - \snippet qmlextensionplugins/plugin.cpp plugin - - The \c TimeModel class receives a \c{1.0} version of this plugin library, as - a QML type called \c Time. The Q_ASSERT() macro can ensure the type namespace is - imported correctly by any QML components that use this plugin. The - \l{Defining QML Types from C++} article has more information about registering C++ - types into the runtime. - - For this example, the TimeExample source directory is in - \c{imports/TimeExample}. The plugin's type namespace will mirror - this structure, so the types are registered into the namespace - "TimeExample". - - Additionally, the project file, in a \c .pro file, defines the project as a plugin library, - specifies it should be built into the \c imports/TimeExample directory, and registers - the plugin target name and various other details: - - \code - TEMPLATE = lib - CONFIG += qt plugin - QT += qml - - DESTDIR = imports/TimeExample - TARGET = qmlqtimeexampleplugin - SOURCES += qexampleqmlplugin.cpp - \endcode - - Finally, a \l{Module Definition qmldir Files}{qmldir file} is required - in the \c imports/TimeExample directory to describe the plugin and the types that it - exports. The plugin includes a \c Clock.qml file along with the \c qmlqtimeexampleplugin - that is built by the project (as shown above in the \c .pro file) so both of these - need to be specified in the \c qmldir file: - - \quotefile qmlextensionplugins/imports/TimeExample/qmldir - - Once the project is built and installed, the new \c Time component is - accessible by any QML component that imports the \c TimeExample - module - - \snippet qmlextensionplugins/plugins.qml 0 - - The full source code is available in the \l {qmlextensionplugins}{plugins example}. - + \include qqmlextensionplugin.qdocinc \section1 Reference |