QQmlImageProviderBase Class

The QQmlImageProviderBase class is used to register image providers in the QML engine. 更多...

頭: #include <QQmlImageProviderBase>
qmake: QT += qml
繼承者: QQuickImageProvider

公共類型

enum Flag { ForceAsynchronousImageLoading }
flags Flags
enum ImageType { Image, Pixmap, Texture, ImageResponse }

公共函數

virtual Flags flags () const = 0
virtual ImageType imageType () const = 0

詳細描述

The QQmlImageProviderBase class is used to register image providers in the QML engine.

Image providers must be registered with the QML engine. The only information the QML engine knows about image providers is the type of image data they provide. To use an image provider to acquire image data, you must cast the QQmlImageProviderBase pointer to a QQuickImageProvider 指針。

另請參閱 QQuickImageProvider and QQuickTextureFactory .

成員類型文檔編製

enum QQmlImageProviderBase:: Flag
flags QQmlImageProviderBase:: Flags

Defines specific requirements or features of this image provider.

常量 描述
QQmlImageProviderBase::ForceAsynchronousImageLoading 0x01 Ensures that image requests to the provider are run in a separate thread, which allows the provider to spend as much time as needed on producing the image without blocking the main thread.

Flags 類型是 typedef 對於 QFlags <Flag>。它存儲 Flag 值的 OR (或) 組閤。

enum QQmlImageProviderBase:: ImageType

Defines the type of image supported by this image provider.

常量 描述
QQmlImageProviderBase::Image 0 The Image Provider provides QImage images. The QQuickImageProvider::requestImage () method will be called for all image requests.
QQmlImageProviderBase::Pixmap 1 The Image Provider provides QPixmap images. The QQuickImageProvider::requestPixmap () method will be called for all image requests.
QQmlImageProviderBase::Texture 2 The Image Provider provides QSGTextureProvider based images. The QQuickImageProvider::requestTexture () method will be called for all image requests.
QQmlImageProviderBase::ImageResponse 4 The Image provider provides QQuickTextureFactory based images. Should only be used in QQuickAsyncImageProvider or its subclasses. The QQuickAsyncImageProvider::requestImageResponse () method will be called for all image requests. Since Qt 5.6

成員函數文檔編製

[pure virtual] Flags QQmlImageProviderBase:: flags () const

Implement this to return the properties of this image provider.

[pure virtual] ImageType QQmlImageProviderBase:: imageType () const

Implement this method to return the image type supported by this image provider.