About the Android broadcast receiver (BroadCastReceiver)

   广播接收者(BroadCastReceiver)是Android的四大组件之一.
   广播事件处理属于系统级的事件处理(一般事件处理为view级的).
   广播事件机制是应用程序之间的通信(进程之间的通信).

context

• sendBroadcast(Intent intent): send general broadcast
• sendOrderedBroadCast(Intent Intent): Send an ordered broadcast
• registerReceiver(receiver, intentFilter): Register a broadcast receiver
• unRegisterReceiver(receiver): Unregister the broadcast receiver

BroadCastReceiver

• onReceive(Context context, Intent intent): Callback when the broadcast is received
• abortBroadcast(): interrupt the continued propagation of broadcast
• boolean isOrderedBroadcast(): Determine whether it is an ordered broadcast

Broadcast receivers must inherit the BroadcastReceiver class.

Register the broadcast receiver:

• Static registration
  Configuration related files: AndroidManifest.xml
  Add:
  
  Application scenario: the entire program life cycle.
• Dynamic registration
  
  Application scenario: some Activity or Service

Broadcast classification:

1. General broadcast
context.sendBroadCast(Intent intent)

• General broadcast: when multiple people answer, it is disorderly and will not be interrupted

2. Orderly broadcast
context.sendOrderedBroadcast(Intent intent)

• Orderly broadcast: When multiple people answer, orderly, it will be interrupted