title: Code behaves differently in Android and Windows
body: <p>I try to draw on a bitmap. This works fine in Windows but creates a segmentation fault in Android (anyhow, that's what Delphi says, I just see no reaction on Android). I have a mobile project, form containing only a TToolbar, TSpeedButton, two TLabels and a TImage. There's just one eventhandler for the TSpeedButton click. </p>
  
  <p>When I comment out everything below the comment the code works fine in Android. When I try to follow with the debugger the code works fine to the end of the procedure. without seeing a drawing or a segmantation fault. When I let it run on the fault occurs.</p>
  
  <p>What am I doing wrong?</p>
  
  <pre><code>procedure TForm2.Button_DrawClick (Sender: TObject);
  var rct: TRectF;
      h, w: Int32;
  begin
    h := Trunc (Image.Height);
    w := Trunc (Image.Width);
    Label_Height.Text := IntToStr (h);
    Label_Width .Text := IntToStr (w);
    rct := TRectF.Create(20, 20, w - 20, h - 20);
  // can be commented out below //
    Image.Bitmap.Create (w, h);
    if Image.Bitmap.Canvas.BeginScene then
    try
      Image.Bitmap.Canvas.Stroke.Color := $FF0000FF;
      Image.Bitmap.Canvas.StrokeThickness := 3;
      Image.Bitmap.Canvas.DrawEllipse (rct, 20);
      Image.Bitmap.Canvas.Stroke.Color := $FF00FF00;
      Image.Bitmap.Canvas.DrawRect(rct, 0, 0, AllCorners, 40);
    finally
      Image.Bitmap.Canvas.EndScene;
    end; // try..finally
  end; // Button_DrawClick //
  </code></pre>