QPictureFormatPlugin Class

QPictureFormatPlugin class provides an abstract base for custom picture format plugins. 更多...

头: #include <QPictureFormatPlugin>
qmake: QT += gui
继承: QObject

该类已过时。 提供它是为使旧源代码能继续工作。强烈建议不要在新代码中使用它。

公共函数

QPictureFormatPlugin (QObject * parent = Q_NULLPTR)
~QPictureFormatPlugin ()
virtual bool installIOHandler (const QString & format ) = 0
virtual bool loadPicture (const QString & format , const QString & fileName , QPicture * picture )
virtual bool savePicture (const QString & format , const QString & fileName , const QPicture & picture )

额外继承成员

详细描述

QPictureFormatPlugin class provides an abstract base for custom picture format plugins.

The picture format plugin is a simple plugin interface that makes it easy to create custom picture formats that can be used transparently by applications.

Writing an picture format plugin is achieved by subclassing this base class, reimplementing the pure virtual functions loadPicture (), savePicture (),和 installIOHandler (),和导出类采用 Q_PLUGIN_METADATA () 宏。

The json file containing the metadata should contain one entry with the list of picture formats supported by the plugin:

{ "Keys": [ "mypictureformat" ] }
					

另请参阅 如何创建 Qt 插件 .

成员函数文档编制

QPictureFormatPlugin:: QPictureFormatPlugin ( QObject * parent = Q_NULLPTR)

Constructs an picture format plugin with the given parent . This is invoked automatically by the moc generated code that exports the plugin.

QPictureFormatPlugin:: ~QPictureFormatPlugin ()

Destroys the picture format plugin.

从不需要明确调用这。Qt 自动销毁插件当不再使用时。

[pure virtual] bool QPictureFormatPlugin:: installIOHandler (const QString & format )

Installs a QPictureIO picture I/O handler for the picture format format 。返回 true 当成功时。

[virtual] bool QPictureFormatPlugin:: loadPicture (const QString & format , const QString & fileName , QPicture * picture )

Loads the picture stored in the file called fileName ,采用给定 format , into * picture 。返回 true 当成功时;否则返回 false .

另请参阅 savePicture ().

[virtual] bool QPictureFormatPlugin:: savePicture (const QString & format , const QString & fileName , const QPicture & picture )

Saves the given picture into the file called fileName ,使用指定 format 。返回 true 当成功时;否则返回 false .

另请参阅 loadPicture ().