一、发送标准广播
Intent intent = new Intent("com.example.broadcasttest. MY_BROADCAST");
sendBroadcast(intent);
二、发送有序广播
Intent intent = new Intent("com.example.broadcasttest. MY_BROADCAST");
sendOrderedBroadcast(intent, null);
截断广播：
public class MyBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context, "received in MyBroadcastReceive", Toast.LENGTH_SHORT).show();
abortBroadcast();
}
}
abortBroadcast();
-
截断后，后续的接收器就不会接收到广播了。
-
接收广播的先后顺序：优先级 android:priority：
<receiver android:name=".MyBroadcastReceiver">
<intent-filter android:priority="100" >
<action android:name="com.example.broadcasttest.MY_BROADCAST"/>
</intent-filter>
</receiver>
三、本地广播
- 前面我们发送和接收的广播全部都是属于系统全局广播，即发出的广播可以被其他任何的任何应用程序接收到，并且我们也可以接收来自于其他任何应用程序的广播。这样就很容易会引起安全性的问题。
- Android 本地广播机制，使用这个机制发出的广播只能够在应用程序的内部进行传递，并且广播接收器也只能接收来自本应用程序发出的广播，这样所有的安全性问题就都不存在了。
- 本地广播是无法通过静态注册的方式来接收的。因为要用时程序肯定已经启动了。
public class MainActivity extends Activity {
private IntentFilter intentFilter;
private LocalReceiver localReceiver;
private LocalBroadcastManager localBroadcastManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
localBroadcastManager = LocalBroadcastManager.getInstance(this); // 获取实例
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent("com.example.broadcasttest. LOCAL_BROADCAST");
localBroadcastManager.sendBroadcast(intent); // 发送本地广播
}
});
intentFilter = new IntentFilter();
intentFilter.addAction("com.example.broadcasttest.LOCAL_BROADCAST");
localReceiver = new LocalReceiver();
localBroadcastManager.registerReceiver(localReceiver, intentFilter); // 注册本地广播监听器
}
@Override
protected void onDestroy() {
super.onDestroy();
localBroadcastManager.unregisterReceiver(localReceiver);
}
class LocalReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context, "received local broadcast", Toast.LENGTH_SHORT).show();
}
}
}
localBroadcastManager = LocalBroadcastManager.getInstance(this); // 获取实例
Intent intent = new Intent("com.example.broadcasttest. LOCAL_BROADCAST");
localBroadcastManager.sendBroadcast(intent); // 发送本地广播
localBroadcastManager.unregisterReceiver(localReceiver);
intentFilter = new IntentFilter();
intentFilter.addAction("com.example.broadcasttest.LOCAL_BROADCAST");
localReceiver = new LocalReceiver();
localBroadcastManager.registerReceiver(localReceiver, intentFilter); // 注册本地广播监听器
