Class CImageTransformPlugin

class CImageTransformPlugin : public CBase;

Description

This is the plugin API for the Image Transform framework Intended for use by plugin writers only.

Derivation

• CBase - Base class for all classes to be instantiated on the heap

• CImageTransformPlugin - This is the plugin API for the Image Transform framework Intended for use by plugin writers only

Members

Defined in CImageTransformPlugin:
CImageTransformPlugin(), CancelTransform(), DestData(), DestFilename(), DestIsData(), DestIsFilename(), DestinationSizeInPixels(), Extension(), MaintainAspectRatio(), OpenL(), Options(), PreserveImageData(), ReservedVirtual1(), ReservedVirtual2(), ReservedVirtual3(), ReservedVirtual4(), SourceData(), SourceFilename(), SourceImageSubType(), SourceImageType(), SourceIsData(), SourceIsFilename(), SourceMimeType(), SourceRect(), Transform(), ~CImageTransformPlugin()

Inherited from CBase:
Delete(), Extension_(), operator new()

IMPORT_C ~CImageTransformPlugin();

Description

This is the destructor for the CImageTransformPlugin and is responsible for deallocating all resources.

protected: IMPORT_C CImageTransformPlugin();

Description

Constructor for this class.

protected: virtual void OpenL()=0;

Description

Initialise the plugin and check the image transform settings.

This is called by the ImageTransform framework when the client app calls CImageTransform::SetupL().

The plugin should check the validity of the source image and all other settings set by the client API. If any of these is unsupported then it should leave with KErrNotSupported.

A plugin implementing CImageTransformPluginExtension to allow extension of the client API should initialise it here.

This is a virtual function that each individual plugin must implement.

Leave codes

KErrUnsupported The plugin decoder doesn not support the request transformation

protected: virtual void Transform(TRequestStatus &aStatus)=0;

Description

Initiate the image transform operation

This is a virtual function that each individual plugin must implement.

Parameters

TRequestStatus &aStatus The client's request status. On completion contains an error code. KErrNone if image was transformed successfully,

protected: virtual void CancelTransform()=0;

Description

Cancel the image transform operation May be called by the framework even when there is no outstanding request.

This is a virtual function that each individual plugin must implement.

protected: IMPORT_C TBool SourceIsFilename() const;

Description

Return whether the source is a file

Return value

TBool ETrue if the source image is stored in a file

protected: IMPORT_C TBool SourceIsData() const;

Description

Return whether the source is data

Return value

TBool ETrue if the source image is stored as data

protected: IMPORT_C const TDesC &SourceFilename() const;

Description

Gets the source file name

Return value

const TDesC & The source file name

Panic codes

EImageWrongType The source is not a file

protected: IMPORT_C const TDesC8 &SourceData() const;

Description

Gets the source descriptor

Return value

const TDesC8 & A reference to the source descriptor

Panic codes

EImageWrongType The source is not a descriptor

protected: IMPORT_C const TDesC8 &SourceMimeType() const;

Description

Gets the source image's MIME type

Return value

const TDesC8 & A reference to the source image's MIME type KNullDesC8 if not defined

protected: IMPORT_C const TUid SourceImageType() const;

Description

Gets the source image's type

Return value

const TUid The UID of the source type KNullUid if not defined

protected: IMPORT_C const TUid SourceImageSubType() const;

Description

Gets the source image's subtype

Return value

const TUid The UID of the source type KNullUid if not defined

protected: IMPORT_C TBool SourceRect(TRect &aRect) const;

Description

Gets the source image's clipping region

Parameters

TRect &aRect The source image's clipping region

Return value

TBool ETrue if a clipping region has been defined

protected: IMPORT_C TBool DestIsFilename() const;

Description

Return whether the destination image is to be stored in a file

Return value

TBool ETrue If the destination image is to be stored in a file

protected: IMPORT_C TBool DestIsData() const;

Description

Return whether the destination image is to be stored as data

Return value

TBool ETrue if the destination image is to be stored as data

protected: IMPORT_C const TDesC &DestFilename() const;

Description

Gets the destination file name

Return value

const TDesC & The destination file name

Panic codes

EImageWrongType The destination is not a file

protected: IMPORT_C HBufC8 *&DestData() const;

Description

Gets the destination descriptor

Return value

HBufC8 *& A reference to a pointer to be used for storing the destination image. The pointer is owned by the client app and is null to start with

Panic codes

EImageWrongType The destination is not a descriptor

protected: IMPORT_C const TSize &DestinationSizeInPixels() const;

Description

Gets the requested size of the destination image

Return value

const TSize & The destination image size

protected: IMPORT_C TUint Options() const;

Description

Gets the options requested by the client

Return value

TUint The options requested by the client

protected: IMPORT_C TBool MaintainAspectRatio() const;

Description

Return whether the client wishes to maintain the source image's aspect ratio

Return value

TBool ETrue if the aspect ratio is to be maintained

protected: IMPORT_C TBool PreserveImageData() const;

Description

Return whether the client wishes to attempt to maintain the original image data

Return value

TBool ETrue if an attempt should be made to preserve the original image data

protected: virtual IMPORT_C CImageTransformPluginExtension *Extension() const;

Description

When a plugin extension has been implemented, this function should be implemented by the plugin writer to enable the client access to the extension

Return value

CImageTransformPluginExtension * A pointer to a fully constructed CImageTransformPluginExtension NULL, if there is no extension to this plugin

private: virtual IMPORT_C void ReservedVirtual1();

Description

Reserved for future-proofing

private: virtual IMPORT_C void ReservedVirtual2();

Description

Reserved for future-proofing

private: virtual IMPORT_C void ReservedVirtual3();

Description

Reserved for future-proofing

private: virtual IMPORT_C void ReservedVirtual4();

Description

Reserved for future-proofing