• 发送有序广播Ordered Broadcast


    import android.os.Bundle;
    import android.app.Activity;
    import android.content.Intent;
    import android.view.Menu;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;

    public class SortedBroadcast extends Activity {
      Button send;

      @Override
      protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sorted_broadcast);
        //获取程序中的send按钮
        send = (Button) findViewById(R.id.send);
        send.setOnClickListener(new OnClickListener() {

          @Override
          public void onClick(View v) {
            // 创建Intent对象
            Intent intent = new Intent();
            intent.setAction(broadcasttest.action.CRAZY_BROADCAST");
            intent.putExtra("msg", "简单的消息");
            //发送有序广播
            sendOrderedBroadcast(intent, null);
          }
        });
      }


    }

    对于有序广播而言,它会按优先级依次触发每个BroadcastReceiver的onReceive()方法。

    import android.content.BroadcastReceiver;
    import android.content.Context;
    import android.content.Intent;
    import android.os.Bundle;
    import android.widget.Toast;

    public class MyReceiver1 extends BroadcastReceiver{

      @Override
      public void onReceive(Context context, Intent intent) {
        Toast.makeText(context, "接收到的Intent的Action为:"+
            intent.getAction()+" 消息内容是:"+intent.getStringExtra("msg"),
            5000).show();
        //创建一个Bundle对象,并存入数据
        Bundle bundle = new Bundle();
        bundle.putString("first", "第一个BroadcastReceiver存入的信息");
        //将Bundle放入结果中
        setResultExtras(bundle);
        //取消Broadcast的继续传播
        abortBroadcast();
      }

    }

    上面的BroadcastReceiver不仅处理了它接收到的消息,而且向处理结果中存入了key为first的消息,这个消息将可以被第二个BroadcastReceiver解析出来。,不过最后一行代码用于取消广播,如果保持这条代码生效,那么优先级比MyReceiver1低的BroadcastReceiver都将不会被触发。

    在AndroidManifest.xml文件中部署该BroadcastReceiver,并指定其优先级为20,配置片段如下:

    <receiver android:name=".MyReceiver1">
      <intent-filter android:priority="20">
        <action android:name="broadcasttest.action.CRAZY_BROADCAST"/>
      </intent-filter>
    </receiver>

    接下来再为程序提供第二个BroadcastReceiver,这个BroadcastReceiver将会解析前一个BroadcastReceiver所存入的key为first的消息,

    import android.content.BroadcastReceiver;
    import android.content.Context;
    import android.content.Intent;
    import android.os.Bundle;
    import android.widget.Toast;

    public class MyReceiver2 extends BroadcastReceiver{

      @Override
      public void onReceive(Context context, Intent intent) {
        Bundle bundle = getResultExtras(true);
        //解析前一个BroadcastReceiver所存入的key为first的消息
        String first = bundle.getString("first");
        Toast.makeText(context, "第一个Broadcast存入的消息为:"+first,5000).show();

      }

    }

    在AndroidManifest.xml文件中部署该BroadcastReceiver,并指定其优先级为0,配置片段如下:

    <receiver android:name=".MyReceiver2">
      <intent-filter android:priority="0">
        <action android:name="broadcasttest.action.CRAZY_BROADCAST"/>
      </intent-filter>
    </receiver>

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  • 原文地址:https://www.cnblogs.com/jiww/p/5613621.html
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