Not able to close the main window

Hi experts,

I am trying to close the main window ( when WD application is executed the html page which displays should be closed ) if i press the exit button.

I have tried using different methods of if_wd_windowcontroller and window_manager none of them worked.

I have used the outbound plug in the window and type of this plug is EXIT. I am triggering this plug in the on action method of corresponding exit button.But output is not coming.

Please give inputs about this.