Android中BroadCastReceiver使用(整理)

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转载自http://www.cnblogs.com/jico/articles/1838293.html

BroadcastReceiver在Android中,Broadcast是一种广泛运用的在应用程序之间传输信息的机制。而BroadcastReceiver是对发送出来的 Broadcast进行过滤接受并响应的一类组件。

下面将详细的阐述如何发送Broadcast和使用BroadcastReceiver过滤接收的过程:

  首先在需要发送信息的地方,把要发送的信息和用于过滤的信息(如Action、Category)装入一个Intent对象,然后通过调用sendOrderBroadcast()或sendStickyBroadcast()方法,把 Intent对象以广播方式发送出去。

  当Intent发送以后,所有已经注册的BroadcastReceiver会检查注册时的IntentFilter是否与发送的Intent相匹配,若匹配则就会调用BroadcastReceiver的onReceive()方法。所以当我们定义一个BroadcastReceiver的时候,都需要实现onReceive()方法。

  注册BroadcastReceiver有两种方式:

  静态注册:在AndroidManifest.xml中用标签生命注册,并在标签内用标签设置过滤器。

  <receiver android:name="myRecevice">    //继承BroadcastReceiver,重写onReceiver方法    <intent-filter>          <action android:name="com.dragon.net"></action> //使用过滤器,接收指定action广播      </intent-filter>  </receiver> 

  动态注册:

IntentFilter intentFilter = new IntentFilter();intentFilter.addAction(String);   //为BroadcastReceiver指定action,使之用于接收同action的广播registerReceiver(BroadcastReceiver,intentFilter);

  一般:在onStart中注册,onStop中取消unregisterReceiver

  指定广播目标Action:Intent intent = new Intent(actionString);

  并且可通过Intent携带消息 :intent.putExtra(“msg”, “hi,我通过广播发送消息了”);

  发送广播消息:Context.sendBroadcast(intent )
  
其中在动态注册中可将BroadcastReceiver的继承类进行封装,添加构造函数和BroadcastReceiver注册

import android.app.Notification;import android.app.NotificationManager;import android.app.PendingIntent;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;public class BroadcastReceiverHelper extends BroadcastReceiver {    NotificationManager mn=null;    Notification notification=null;    Context ct=null;    BroadcastReceiverHelper receiver;    public BroadcastReceiverHelper(Context c){        ct=c;        receiver=this;    }    //注册    public void registerAction(String action){        IntentFilter filter=new IntentFilter();        filter.addAction(action);        ct.registerReceiver(receiver, filter);    }    @Override    public void onReceive(Context context, Intent intent) {        // TODO Auto-generated method stub        String msg=intent.getStringExtra("msg");        int id=intent.getIntExtra("who", 0);            if(intent.getAction().equals("com.cbin.sendMsg")){                mn=(NotificationManager)context.getSystemService(Context.NOTIFICATION_SERVICE);                notification=new Notification(R.drawable.icon, id+"发送广播", System.currentTimeMillis());                Intent it = new Intent(context,Main.class);                PendingIntent contentIntent=PendingIntent.getActivity(context,                        0, it, 0);                notification.setLatestEventInfo(context,                         "msg", msg, contentIntent);                mn.notify(0, notification);            }    }}

然后再Activity中声明BroadcastReceiver的扩展对象,在onStart中注册,onStop中卸载

代码BroadcastReceiverHelper  rhelper;@Override    public void onStart(){        //注册广播接收器        rhelper=new BroadcastReceiverHelper(this);        rhelper.registerAction("com.cbin.sendMsg");        super.onStart();    }    @Override    public void onStop(){        //取消广播接收器        unregisterReceiver(rhelper);        super.onStop();    }
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