application crashes while using a method of different class

Question

I am developing a SIP application for incoming and outgoing calls and i want to show AlertDialog on incoming call. For that i had put two butto

Answer 1

did you created instance?

incomingCallReceiver=new IncomingCallReceiver();

or change you method to static

public static void acceptCall() 

//and call this in your IncomingCallPage

IncomingCallReceiver.acceptCall()