How to set mandatory a InputField in standard Web Dynpro component?

Question

Hi guys.
A very weird thing is happening. I am trying to validate that a non-mandatory STANDARD input field (COST_ASSIGNMENT) does not to be empty. This input field belongs to GENERAL_DATA_VIEW, FITE_VC_GENERAL_DATA WD component. The entry fields at screen belong to this GENERAL_DATA_VIEW, but navigation is allocated in buttons that belong to another component (LAYOUT_VIEW in the FITV_FPM WD component). All the views and components are standard and they seem to be in the same screen from user's point of view. I was able to put my own code at WDDOAFTERACTION method in LAYOUT_VIEW to raise an error message.
Incredibly, my error text message appears in the MESSAGEAREA, and the UI components from GENERAL_DATA_VIEW are rightly still in the screen waiting for user answer since I set CANCEL_NAVIGATION = 'X', but the UI components from LAYOUT_VIEW (the buttons with navigate functions) changed like they had accepted my entry in spite of I set the code in this view. In fact, below my error text displayed, there is other (success) text which communicates "Standing approval for business trips exists" with a green tick.
The success text should not be displayed since I raised an error message, even after (I think so) the system created the success message.  I suspect that the standard positive message with the green tick indicates that my error is being taking into acccount by the system to be displayed but the LAYOUT_VIEW UI components dont stop navigation and the data is wrongly saved from the code where the success message was generated.
I think there would be another way to define an standard inputfield mandatory, but I dont know how to do it. Do you know that? I really appreciate all help. Thanks

Answer 1

hi,
just make the input feild as mandatory in properties and use the following code.
data:
lo_view_controller type ref to if_wd_view_controller,
lo_dyn type ref to cl_wd_dynamic_tool.
Create Object
create object lo_dyn.
data lt_messages type lo_dyn->t_check_result_message_tab.
Get view controller reference
lo_view_controller = wd_this->wd_get_api( ).
Call Method to verify the element has the value or not
call method cl_wd_dynamic_tool=>check_mandatory_attr_on_view
exporting
view_controller = lo_view_controller
display_messages = ABAP_TRUE
importing
messages = lt_messages .
endmethod.
Regards,
Kranthi