Android广播的使用（一）

Android广播分为两个方面：广播发送者和广播接收者BroadcastReceiver。

BroadcastReceiver可以分为两种注册类型：静态注册和动态注册。

静态注册：直接在AndroidManifest.xml文件中进行注册。

动态注册：直接在代码中调用Context的registerReceiver函数。

动态注册：

Activity类代码：

public class MainActivity extends Activity {
	private static final String SERVICE_NAME = "com.seasy.android.MyRemoteService";
	private static final String BROADCAST_ACTION = "com.seasy.android.MyBroadcastReceiver";
	private MyBroadcastReceiver broadcastReceiver;
	private TextView txtMessage = null;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		
		txtMessage = (TextView)findViewById(R.id.txtMessage);
		
		doRegisterReceiver();
		
		//启动Service
		Intent serviceIntent = new Intent(MainActivity.this, MyRemoteService.class);
        startService(serviceIntent);
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		doUnregisterReceiver();
	}
	
	/**
	 * 注册广播接收者
	 */
	private void doRegisterReceiver(){
		broadcastReceiver = new MyBroadcastReceiver();
        IntentFilter intentFilter = new IntentFilter(BROADCAST_ACTION);
        registerReceiver(broadcastReceiver, intentFilter);
	}
	
	/**
	 * 注销广播接收者
	 */
	private void doUnregisterReceiver(){
		unregisterReceiver(broadcastReceiver);
	}

	public TextView getTxtMessage() {
		return txtMessage;
	}

	//广播接收器类：收到广播消息后，将消息显示在界面的文本框中
	class MyBroadcastReceiver extends BroadcastReceiver {
		@Override
		public void onReceive(Context context, Intent intent) {
			String messageData = intent.getStringExtra("messageData");
			getTxtMessage().setText(messageData);
		}
	}
}

Service类代码：

public class MyRemoteService extends Service {
	private static final String BROADCAST_ACTION = "com.seasy.android.MyBroadcastReceiver";
	
	@Override
	public void onCreate() {
		super.onCreate();
		sendBroadcastMessage("Start Thrift Server");
	}
	
	@Override
	public IBinder onBind(Intent intent) {
		return null;
	}
	
	/**
	 * 发送广播
	 */
	private void sendBroadcastMessage(String messageData){
		Intent intent = new Intent();
        intent.setAction(BROADCAST_ACTION);
        intent.putExtra("messageData", messageData);
        sendBroadcast(intent);
	}
}

在AndroidManifest.xml文件中添加如下配置信息：

<service android:name="com.seasy.android.MyRemoteService" android:exported="false"></service>