Android中广播接收者BroadcastReceiver详解

 1 public class SdCardBroadcastReceiver extends BroadcastReceiver {
 2 
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         String action = intent.getAction();
 6         if("android.intent.action.MEDIA_MOUNTED".equals(action)){
 7             System.out.println("sd卡已挂载");
 8         }else if("android.intent.action.MEDIA_UNMOUNTED".equals(action)){
 9             System.out.println("sd卡已卸载");
10         }
11     }
12 
13 }

1 <!-- 相当于装电池 -->
2         <receiver android:name="com.example.sdbroadcast.SdCardBroadcastReceiver">
3             <!-- 相当于调频道 -->
4             <intent-filter>
5                 <action android:name="android.intent.action.MEDIA_MOUNTED"/>
6                 <action android:name="android.intent.action.MEDIA_UNMOUNTED"/>
7                 <data android:scheme="file"/>
8             </intent-filter>
9         </receiver>

1  <!-- 相当于调频道 -->
2             <intent-filter>
3                 <action android:name="android.intent.action.MEDIA_MOUNTED"/>
4                 <action android:name="android.intent.action.MEDIA_UNMOUNTED"/>
5                 <data android:scheme="file"/>
6             </intent-filter>

 1 public void startBroadcast(View view){
 2         //开启广播
 3         //创建一个意图对象
 4         Intent intent = new Intent();
 5         //指定发送广播的频道
 6         intent.setAction("com.example.BROADCAST");
 7         //发送广播的数据
 8         intent.putExtra("key", "发送无序广播,顺便传递的数据");
 9         //发送
10         sendBroadcast(intent);
11     }

 1 public class UnorderedReceiver extends BroadcastReceiver {
 2 
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         String action = intent.getAction();
 6         
 7         String data = intent.getStringExtra("key");
 8         
 9         System.out.println("接受到了广播,action:"+ action +",data:"+data);
10         
11         //接受到了广播,action:com.example.BROADCAST,data:发送无序广播,顺便传递的数据
12     }
13 
14 }

1 <receiver android:name="com.example.selfreceiver.UnorderedReceiver">
2             <intent-filter>
3                 <action android:name="com.example.BROADCAST"/>
4             </intent-filter>
5         </receiver>

 1 // 发送有序广播
 2     public void sendOrderedBroad(View view) {
 3         Intent intent = new Intent();
 4         intent.setAction("com.example.ORDERED");
 5         // 发送无序广播
 6         sendOrderedBroadcast(intent,//意图动作,指定action动作
 7                 null, //receiverPermission,接收这条广播具备什么权限
 8                 new FinalReceiver(),//resultReceiver,最终的广播接受者,广播一定会传给他
 9                 null, //scheduler,handler对象处理广播的分发
10                 0,//initialCode,初始代码
11                 "每人发10斤大米,不得有误!", //initialData,初始数据
12                 null//initialExtras,额外的数据,如果觉得初始数据不够,可以通过bundle来指定其他数据
13                 );
14     }

 1 public class ShengReceiver extends BroadcastReceiver {
 2 
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         
 6         //获取广播的数据
 7         String data = getResultData();
 8         
 9         //修改
10         setResultData("中央下达福利,每人5斤大米");
11         
12         System.out.println("省政府收到指示, data : "+data);
13     }
14 
15 }

 1 public class PeopleReceiver extends BroadcastReceiver {
 2 
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         //获取广播的数据
 6         String data = getResultData();
 7         System.out.println("老百姓收到福利,感谢党, data : "+data);
 8     }
 9 
10 }

 1 public class ShengReceiver extends BroadcastReceiver {
 2 
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         
 6         //获取广播的数据
 7         String data = getResultData();
 8         
 9         //也可以终止广播,权限小的接收者就接收不到广播了
10         abortBroadcast();
11         
12         System.out.println("省政府收到指示, data : "+data);
13     }
14 
15 }

1 public class FinalReceiver extends BroadcastReceiver {
2 
3     @Override
4     public void onReceive(Context context, Intent intent) {
5         String resultData = getResultData();
6         System.out.println("人民收到的最终福利是: "+ resultData);
7     }
8 
9 }