TGraphic

type TGraphic = class(TPersistent)

protected

  procedure Changed(); virtual;

Changed - software emulation of a call to the OnChange event

  function Equals(); virtual;

Equals - returns True if the current Graphic is the same as the specified Graphic

  procedure DefineProperties(); override;

DefineProperties finds out whether the object really is a binary (graphic)

  procedure Draw(); virtual; abstract;

Method to Draw the Graphic on the specified Canvas, in the specified Rectangle

  function GetEmpty; virtual; abstract;

GetEmpty - returns True if the Graphic is empty

  function GetHeight; virtual; abstract;

GetHeight - returns the height of the Graphic

  function GetMimeType; virtual;

GetMimeType - returns the MIME type of the Graphic

  function GetPalette; virtual;

GetPalette - returns a Handle for the Palette

  function GetTransparent; virtual; abstract;

GetTransparent - returns True if the graphic is transparent

  function GetWidth; virtual; abstract;

GetWidth - returns the width of the Graphic

  procedure Progress();

Monitor the Progress of the drawing

  procedure ReadData(); virtual;

ReadData - reads data for the Graphic from a stream

  procedure SetHeight(); virtual; abstract;

SetHeight - defines the height for the Graphic

  procedure SetPalette(); virtual;

SetPalette - deefines the Palette Handle to be used

  procedure SetTransparent(); virtual; abstract;

SetTransparent - defines whether the graphic is to be transparent

  procedure SetWidth(); virtual; abstract;

SetWidth - defines the width for the Graphic

  procedure SetModified();

SetModified - defines whether the graphic has been modified

  procedure WriteData(); virtual;

WriteData - writes Graphic data to a stream

public

  procedure Assign(); override;

Assign - checks if there really is a source to assign (if not, calls Clear), then calls inherited method

  constructor Create; virtual;

Create - constructor for TGraphic: calls inherited Create

  procedure Clear; virtual;

Clear the resources used by the Graphic, leaving a blank Graphic

  function LazarusResourceTypeValid(); virtual;

Check that the Resource specified for reading or writing is a valid type - result True if it is

  procedure LoadFromFile(); virtual;

LoadFromFile - Read the graphic from the file system.

  procedure LoadFromStream(); virtual; abstract;

LoadFromStream - reads graphic data from a stream (e.g. TBlobStream )

  procedure LoadFromMimeStream(); virtual;

LoadFromMimeStream - reads graphic data from a MIME stream

  procedure LoadFromLazarusResource(); virtual;

Load the graphic data from a Lazarus Resource (eg a *.lrs file)

  procedure LoadFromResourceName(); virtual;

Load the graphic data from a resource identified by the name ResName with the Handle 'Instance'

  procedure LoadFromResourceID(); virtual;

Load graphic data from a resource identified by the integer identifier ResID

  procedure LoadFromClipboardFormat(); virtual;

LoadFromClipboardFormat - Replace the current image with the contents of the clipboard

  procedure LoadFromClipboardFormatID(); virtual;

Load the data from the clipboard using the format type specified by ClipboardType and the format identifier FormatID

  procedure SaveToFile(); virtual;

SaveToFile - Writes the graphic to disk in the file provided.

  procedure SaveToStream(); virtual; abstract;

SaveToStream - write graphic data to a stream

  procedure SaveToClipboardFormat(); virtual;

SaveToClipboardFormats - Converts the image to a clipboard format

  procedure SaveToClipboardFormatID(); virtual;

Saves the data to a clipboard of Type ClipboardType using the format FormatID

  procedure GetSupportedSourceMimeTypes(); virtual;

Gets a list of the MIME types that are supported

  function GetResourceType; virtual;

GetResourceType - returns the type of a resource to be used in the graphic

public

  class function GetFileExtensions; virtual;

GetFileExtensions - returns a list of the file extensions available

  class function IsStreamFormatSupported(); virtual;

public

  property Empty: Boolean; [r]

Is this an empty (blank) graphic?

  property Height: Integer; [rw]

Height - The native, unstretched, height of the graphic.

  property Modified: Boolean; [rw]

Has the graphic been modified?

  property MimeType: String; [r]

MimeType - the MIME type of the graphic

  property OnChange: TNotifyEvent; [rw]

Event handler for any change in the data

  property OnProgress: TProgressEvent; [rw]

Event handler for monitoring progress of the graphic

  property Palette: HPALETTE; [rw]

Palette - Color palette of image

  property PaletteModified: Boolean; [rw]

Has the palette of colours been modified?

  property Transparent: Boolean; [rw]

Transparent - Some parts of the image are not opaque. ie the background can be seen through

  property Width: Integer; [rw]

Width - The native, unstretched, width of the graphic.

end;

TGraphic

TGraphic - Base class for dealing with Graphic images

TPersistent

TObject