> I have tried to add an icon for my app. at the task bar ,
>
> I did it , but still don't know how to make that icon responds to events
> such  as mouse right click ,
>
> when I right click the mouse on it I want to show a popup that restores
> or closes my application any help will be very appreciated (pls some
> code)
 

You need to handle the task icon message. For example, define a message handler
somewhere in your unit like,

const WM_TASKICON = WM_USER+0;
..
procedure WMTASKICON(var msg : TMessage); message WM_TASKICON;

Then implement this handler to handle mouse events like,

procedure TTaskIcon.WMTASKICON(var msg : TMessage);
begin
        case msg.lParam of
             WM_LBUTTONDBLCLK : DoSomething;
             WM_LBUTTONUP     : DoSomething;
             WM_RBUTTONUP     : DoSomething;
        end;
end;

Then assign this message to the uCallbackMessage member of TNOTIFYICONDATA
variable like,

var
idata : TNOTIFYICONDATA;
..
idata.uCallbackMessage := WM_TASKICON;