TPopupMenu.OnPopup Event

Occurs just before the pop-up menu appears.

Pascal

property OnPopup: TNotifyEvent;

C++

__property TNotifyEvent OnPopup;

Description

Write an OnPopup event handler to take specific action just before the pop-up menu appears. For example, use an OnPopup event handler to set the Checked, Enabled, or Visible property of individual items in the menu so that they are appropriate to the PopupComponent.

C++ Examples:

Copy Code

/*
The following code enables the Copy item from the pop-up
menu if the edit control has a nonempty selection.
Note: A portion of the edit control text must be highlighted.
*/
void __fastcall TForm1::PopupMenu1Popup(TObject *Sender)
{
  Copy1->Enabled = (Edit1->SelLength > 0);
}

void __fastcall TForm1::Copy1Click(TObject *Sender)
{
    ListBox1->Items->Add("'Copy' menu");
}

void __fastcall TForm1::FormMouseDown(TObject *Sender, TMouseButton Button, TShiftState Shift,
          int X, int Y)
{
  PopupMenu1->Popup(X, Y);
}

Delphi Examples:

Copy Code

{
The following code enables the Copy item from the pop-up
menu if the edit control has a nonempty selection.
Note: A portion of the edit control text must be highlighted.
}
procedure TForm1.PopupMenu1Popup(Sender: TObject);
begin
  Copy1.Enabled := Edit1.SelLength > 0;
end;

procedure TForm1.Copy1Click(Sender: TObject);
begin
    ListBox1.Items.Add('"Copy" menu');
end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  PopupMenu1.Popup(Left + X, Top + Y);
end;