Check drop down status

Hi,

Ive MVC UI5 project with controller and fragment,in the fragment I've Drop down which is getting the data from

the controller,most of the time the service are providing data to the ddl but in some cases not.

in case that the drop down is not getting data from the controller I want to display text no customers found instead the drop down

i.e. not to draw the drop down at all,how can I do that ?

Example will be very helpful since Im very new to UI5

Thanks