How to draw on the entire area of a resized TImage in Delphi?

Answer 1

Maybe you have to also adjust Image1.Picture.Width/Height or Image1.Picture.Bitmap.Width/Height.

Answer 2

Add an OnResize-event to your form:

procedure TForm1.FormResize(Sender: TObject);
begin
  Image1.Picture.Bitmap.Width := Image1.Width;
  Image1.Picture.Bitmap.Height := Image1.Height;
end;

Also, if you are using the component to draw on, rather than displaying images from file etc, consider using the TPaintBox rather than TImage.