TCustomImageListResolution.ReadData procedure

Declaration

procedure ReadData(AStream: TStream); virtual

Arguments

Description

ReadData is a procedure used to read the raw image data for all images in the resolution from the specified stream.

AStream contains the TStream class instance with the raw image data read in the method. The current position in AStream is used when values are read in the method. The stream is positioned immediately after the raw image values when values are read in the method.

ReadData calls the Clear method to remove any existing image data stored in the resolution.

ReadData reads the signature for the image list from the stream. The signature identifies whether image data was written by various versions of the Lazarus or Delphi IDEs, and defines the header information expected in the stream. Methods are provided to read header and image data for the following image list signatures:

SIG_LAZ1

Earlier versions of the Lazarus IDE

SIG_LAZ2

Lazarus versions that included header data for each image

SIG_LAZ3

Current Lazarus image list format using uncompressed image data

SIG_LAZ4

Current Lazarus image list format using compression for image data

SIG_D3

Delphi 3 image list format

If an image list signature is not found, it was created using the Delphi 2 image list format which did not include a signature. In this scenario, the stream in AStream is moved to its original position prior to reading image data from the stream.

ReadData is used in the implementation of the TCustomImageList.ReadData method.

Visibility changed in LCL version 5.0.

See also

• ReadData