Hey guys,
i think i have explored the whole internet in the meanwhile 
. I have created different Webdynpros which include mandatory and non mandatory fields.
First i tried to check these fields in the component itself in the wddobeforeaction method. That was not a big deal. After that I transfered the check in the controller so that it is executed when I klick the save button in my floorplan.
Now i have searched for a solution to check all webdynpro components included in the floorplan by the floorplan itself and not longer by the components.
The problem is that only the process event method of the visible uibb is executed. I want the floorplan to check WD Component 1 (Tab 1) and WD Component 2 (Tab 2). The result should be that if I fill in the mandatory fields of Component 1 and dont fill the fields of Component 2 and press 'Save' after the floorplan should raise the error messages for the non filled fields of Component 2.
I have found the solution in the App Controller so I have created a new Webdynpro with the 'IF_FPM_APP_CONTOLLER' interface implemented. Furthermore I have implemented the 'IF_FPM_OIF_CONF_EXIT' interface here to override the process_event method. Is this the right way? How can I get to the view controller of every WD Comp in the AppCC to check the mandatory fields?
Thank you very much
Greetings Tim