| 知乎专栏 |
注意:LocalBroadcastManager 已经被废弃
上面讲的系统广播是全局的,任何APP都能接收到你的广播,这样就很容易引起APP的安全性问题。很多时候我们只想接收来自本应用程序发出的广播。
package cn.netkiller.broadcast;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
private TextView textView;
private IntentFilter intentFilter;
private LocalBroadcastManager localBroadcastManager;
private MyBroadcastReceiver myBroadcastReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//获取LocalBroadcastManger 单li实例
localBroadcastManager = localBroadcastManager.getInstance(this);
intentFilter = new IntentFilter();
intentFilter.addAction("cn.netkiller.broadcast.MESSAGE");
myBroadcastReceiver = new MyBroadcastReceiver();
//注册本地广播接收器
localBroadcastManager.registerReceiver(myBroadcastReceiver, intentFilter);
textView = (TextView) findViewById(R.id.textView);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
textView.setText("Send");
Intent intent = new Intent();
intent.setAction("cn.netkiller.broadcast.MESSAGE");
intent.putExtra("msg", "http://www.netkiller.cn");
//发送本地广播
localBroadcastManager.sendBroadcast(intent);
}
});
}
@Override
protected void onDestroy() {
super.onDestroy();
//注销本地广播接收器
localBroadcastManager.unregisterReceiver(myBroadcastReceiver);
}
//自定义内部类,继承 BroadcastReceiver
public class MyBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
String data = intent.getStringExtra("msg");
Toast.makeText(context, data, Toast.LENGTH_SHORT).show();
}
}
}