Even when using the ImageIDRequest trick shown in the documentation, the images are still not transparent:
procedure AddImageListToImageEnMView(ImageList: TImageList; ImageEnMView: TImageEnMView);
var
i: Integer;
begin
ImageEnMView.Clear;
// Add an ID for every bitmap in a TImageList
for i := 0 to ImageList.Count - 1 do
begin
ImageEnMView.InsertImage(I);
ImageEnMView.ImageID[I] := I;
end;
end;
procedure TForm1.ImageEnMView1ImageIDRequest(Sender: TObject; Index, ID: Integer; var Bitmap: TBitmap);
begin
// Retrieve the image from a TImageList
Bitmap := TBitmap.create;
ImageList1.GetBitmap(ID, Bitmap);
end;