I can see a potential problem in the screenshots you sent me. First of all the problem is a NullPointerException. Now we must figure out where is it coming from. This error occurs when you try to invoke functionality of an object, that is not initiated (its null at the moment).
I suspect that this line of code doesn't find the calendar and returns null:
RadCalendarView calendarView = (RadCalendarView)findViewById(R.id.calendarView);
Therefore on the next line you try to set the display mode, but since the calendar is still null you get a NullPointerException.
Please make sure that you have the calendar defined somewhere in the activity_main.xml file, that you are using for the current activity. It should look something like this:
Please let me know how this goes. I am pretty sure that would be the problem.
Thank you for your time and all best!
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