Event during DragMove?

For TL;DR:

In my application TouchAssistant I want it disappear after few seconds if no user interaction, however, after called DragMove(), there is no chance for me to listen to extra events to know if user still interacted with the program.

Long Version:

There is a very good explanation about it from this Link.

DragMove starts a modal message loop and doesn’t return until the mouse button is released, so by the time the button receives the MouseLeftButtonDown event it’s already lost the chance to click.

The solution is simple, just set a variable before executing DragMove, and unset the variable after the execution. Your program can depend on this variable.