How to check before action "Close SAP-GUI (Modus)"???

Hi at all,

iám searching events or functions where i can programming my check-logic before the SAP-GUI(Modus) is closed.

For example i have created a Selection-Screen and the User will close the Window by clicking on the SAP GUI function: close ("X"), but before the SAP Window is closing, it should ask again in a POP-UP!

I have searched in the Class: "CL_IMC_MODE" for trigger-Methods, but nothing found.

Have anyone an idea???

Regards

ETN