广播的动作分别为：注册、发送、接收。

1. 定义接收器

public class MyReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {}
}

2. 注册广播

final MyReceiver[] receivers = {null};Button registerBroad = findViewById(R.id.registerBroadcast);registerBroad.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {receivers[0] = new MyReceiver();IntentFilter intentFilter = new IntentFilter();intentFilter.addAction("sendMSG");registerReceiver(receivers[0],intentFilter);}});

3. 发送广播

Button sendBroadcast = findViewById(R.id.sendBroadcast);sendBroadcast.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {Intent intent = new Intent();intent.setAction("sendMSG");intent.putExtra("msg","it is the Broadcast message");sendBroadcast(intent);}});

4. 定义接收到广播后的行为

public class MyReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {Log.i("Test","MSG received"+intent.getStringExtra("msg"));}
}