Callback to the caller: occurs when the callee accepts the call invitation.
Callback to the caller: occurs when the caller cancels a call invitation. This callback notifies the caller that he/she has canceled a call invitation.
Callback to the caller: occurs when the outgoing call invitation ends in failure.
Callback to the caller: occurs when the callee receives the call invitation.
This callback notifies the caller that the callee receives the call invitation.
Callback to the caller: occurs when the callee refuses the call invitation.
Event types of the LocalInvitation instance.