Qt 5.9 | Qt QML | C++ Classes | QQmlImageProviderBase

Qt 5.9.9 Reference Documentation

# QQmlImageProviderBase Class

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

Header: | #include <QQmlImageProviderBase>
qmake: | QT += qml

- List of all members, including inherited members

## Public Types

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

## Public Functions

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

## Detailed Description

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 pointer.

See also QQuickImageProvider and QQuickTextureFactory.

## Member Type Documentation

### enum QQmlImageProviderBase::Flag
flags QQmlImageProviderBase::Flags

Defines specific requirements or features of this image provider.

Constant | Value | Description
--- | --- | ---
`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.

The Flags type is a typedef for QFlags<Flag>. It stores an OR combination of Flag values.

### enum QQmlImageProviderBase::ImageType

Defines the type of image supported by this image provider.

Constant | Value | Description
--- | --- | ---
`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

## Member Function Documentation

### `[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.