iOS监听电话事件

#import <CoreTelephony/CTCallCenter.h>
#import <CoreTelephony/CTCall.h>

@property (nonatomic, strong) CTCallCenter *callCenter;

 　　self.callCenter = [[CTCallCenter alloc] init];
    self.callCenter.callEventHandler=^(CTCall* call)
    {
        if (call.callState == CTCallStateDisconnected)
        {
            NSLog(@"挂断电话Call has been disconnected");     
        }
        else if (call.callState == CTCallStateConnected)
        {
             NSLog(@"电话通了Call has just been connected");  
        }

        else if(call.callState == CTCallStateIncoming)
        {
            NSLog(@"来电话了Call is incoming");  

        }

        else if (call.callState ==CTCallStateDialing)
        {
            NSLog(@"正在播电话call is dialing");  
        }
        else
        {
            NSLog(@"Nothing is done");  
        }
    };