Android 广播接收器BroadcastReceiver

最新推荐文章于 2022-11-20 14:16:44 发布

原创最新推荐文章于 2022-11-20 14:16:44 发布 · 472 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#广播 #broadcastreceiver

本文详细介绍了如何在Android应用中创建并使用广播接收器MyReceiver。包括广播接收器的定义、如何发送广播、如何动态注册及注销广播接收器，以及如何设置广播的优先级等内容。

新建一个MyReceiver

public class MyReceiver extends BroadcastReceiver {
    public MyReceiver() {
    }

    @Override
    public void onReceive(Context context, Intent intent) {
       System.out.print("接受消息"+intent.getStringExtra("data"));
    }
}

public class MainActivity extends Activity implements View.OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.sendMessage).setOnClickListener(this);
    }
    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.sendMessage:
            //intent传递数据
                Intent i = new Intent(new Intent(this,MyReceiver.class));
                i.putExtra("data","jikedfa");
                sendBroadcast(i);
                break;
        }
    }
}

动态注册和注销

MyReceiver

public class MyReceiver extends BroadcastReceiver {
//添加ACTION
    public static final String ACTION = "sw.cins.com.service.intent.action.MyReceiver";
    public MyReceiver() {
    }

    @Override
    public void onReceive(Context context, Intent intent) {
       System.out.print("接受消息"+intent.getStringExtra("data"));
    }
}

MainActivity

public class MainActivity extends Activity implements View.OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.sendMessage).setOnClickListener(this);
        findViewById(R.id.btnreg).setOnClickListener(this);
        findViewById(R.id.btnunreg).setOnClickListener(this);
    }
    private MyReceiver receiver = null;
    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.sendMessage:
                Intent i = new Intent(MyReceiver.ACTION);
                i.putExtra("data","jikedfa");
                sendBroadcast(i);
                break;
            case R.id.btnreg:
                if(receiver == null){
                    //注册
                    receiver = new MyReceiver();
                    registerReceiver(receiver,new IntentFilter(MyReceiver.ACTION));
                }
                break;
            case R.id.btnunreg:
                if(receiver != null){
                    //注销
                    unregisterReceiver(receiver);
                    receiver = null;
                }
                break;
        }
    }
 }

优先级控制

<receiver
            android:name=".MyReceiver"
            android:enabled="true"
            android:exported="true">
            //通过priority控制优先级，数值越大，优先级越高
            <intent-filter  android:priority="10">

            </intent-filter>
        </receiver>