ImageEn, unit imageenview |
|
TImageEnView.OnDrawLayer
Declaration
property OnDrawLayer: TIEDrawLayerEvent;
Description
Occurs immediately after a layer is painted.
Parameter | Description |
Dest | The destination bitmap (usually the back buffer) |
LayerIndex | The layer index that we are drawing |
Notes:
- Use
Layers[].
ClientAreaBox rectangle to know actual rectangle coordinates
- With
TImageEnView.OnDrawLayer,
Dest is the entire image the layer has been painted to. With
OnBeforeDrawLayer,
Dest is only the layer as an image
Demos
| Demos\LayerEditing\Layers_CustomDraw\LayersDraw.dpr |
Example
// Display the index over the layer
procedure Tfmain.ImageEnView1DrawLayer(Sender: TObject; dest: TIEBitmap; LayerIndex: Integer);
var
lyrRect, aRect: TRect;
begin
lyrRect := ImageEnView1.Layers[ LayerIndex ].ClientAreaBox;
aRect := Rect( lyrRect.Left + 10, lyrRect.Top + 10, lyrRect.Left + 40, lyrRect.Top + 40 );
With dest.Canvas do
begin
// Simple example: Would be better to center text in filled rect
Brush.Color := clBlue;
FillRect( aRect );
Font.Color := clWhite;
Font.Height := 12;
Font.Style := [fsBold];
TextRect( aRect, lyrRect.Left + 20, lyrRect.Top + 20, IntToStr( LayerIndex ));
end;
end;