QPictureFormatPlugin Class

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

Header: #include <QPictureFormatPlugin>
qmake: QT += gui
Inherits: QObject

This class is obsolete. It is provided to keep old source code working. We strongly advise against using it in new code.

Public Functions

QPictureFormatPlugin(QObject *parent = nullptr)
virtual ~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)

Detailed Description

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(), and installIOHandler(), and exporting the class with the Q_PLUGIN_METADATA() macro.

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

{ "Keys": [ "mypictureformat" ] }

See also How to Create Qt Plugins.

Member Function Documentation

QPictureFormatPlugin::QPictureFormatPlugin(QObject *parent = nullptr)

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

[virtual] QPictureFormatPlugin::~QPictureFormatPlugin()

Destroys the picture format plugin.

You never have to call this explicitly. Qt destroys a plugin automatically when it is no longer used.

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

Installs a QPictureIO picture I/O handler for the picture format format. Returns true on success.

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

Loads the picture stored in the file called fileName, with the given format, into *picture. Returns true on success; otherwise returns false.

See also savePicture().

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

Saves the given picture into the file called fileName, using the specified format. Returns true on success; otherwise returns false.

See also loadPicture().

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