⤷ Get MessageDlg relative to form

This example shows a creation of Message Dialog relative to center of Form1.

procedure TForm1.Button1Click(Sender: TObject);
var
  MyForm: TForm;
begin
  MyForm:=CreateMessageDialog('This is example', mtInformation, [mbOk]);
  with MyForm do
  begin
    Height:=130;
    Width:=150;
    Left:=Trunc((Form1.Width-Width)/2)+Form1.Left;
    Top:=Trunc((Form1.Height-Height)/2)+Form1.Top;;
    ShowModal;
  end;
end;
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