在Android中阻止来电

Question

I want to block/unblock incoming call in my android app. I am able to do that using below code.

telephony = (TelephonyManager) this.getSystemService(Context.TELEPHONY_SERVICE);
customPhoneListener = new PhoneCallStateListener(MainActivity.this, vSMS);
start.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        telephony.listen(customPhoneListener, 
                         PhoneStateListener.LISTEN_CALL_STATE);
        Toast.makeText(MainActivity.this, "START", Toast.LENGTH_SHORT).show();
    }
});

stop.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        telephony.listen(customPhoneListener,
                         PhoneStateListener.LISTEN_NONE);
        Toast.makeText(MainActivity.this, "STOP", Toast.LENGTH_SHORT).show();
        }
    });
}

But problem is that when I click on start button call blocking service activated and then we go to home page call blocking is still in activate mode.(that's fine). but when I open my app and press stop button then call doesn't unblock. it still blocked. why? what I am doing wrong?

Answer 1

You are getting the telephone object using the activity context and the customPhoneListener I guess is defined as instance variable in your activity.

But when you close the activity (by going to home screen) and open it again, you have a new context so the stop button almost does nothing.

To resolve this you can try the following:

1- User application context

telephony = (TelephonyManager)  getApplicationContext().getSystemService(Context.TELEPHONY_SERVICE);

2- Ensure that the listener object customPhoneListener is the same during the life cycle of your application not your activity. Try to make it static or define it in the application class