Android开发——四大组件BroadcastReceiver实例广播事件的拦截转发

  我们通过一个实例来认识一下BroadcastReceiver广播接收器。我们两个广播接收器我们用不同的方式去注册，然后设置一个优先级，第一个广播优先级更高，让第一个广播事件给第二个增加一些内容。

在manifest中注册并设置第一个广播的优先级为最高（-1000~1000，1000为最高）

<receiver android:name="com.example.broadcastreceiver.firstBroadReveiver">
            <intent-filter
                android:priority="1000">
                <action android:name="briup"/>
            </intent-filter>
</receiver>

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.broadcastreceiver.MainActivity" >

    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="btn"/>
</RelativeLayout>

MainActivity.java

package com.example.broadcastreceiver;
import android.app.Activity;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends Activity {
	private SecandBroadReveiver secandBroadReveiver;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		secandBroadReveiver=new SecandBroadReveiver();
		IntentFilter filter=new IntentFilter();
		filter.addAction("briup");
		registerReceiver(secandBroadReveiver,filter);
	}
	public void btn(View view) {
		// TODO Auto-generated method stub
		Intent intent=new Intent();
		intent.setAction("briup");
		intent.putExtra("data", "原来的广播");
		sendOrderedBroadcast(intent, null);
		//sendBroadcast(intent);
	}
}

firstBroadcastReceiver.java

package com.example.broadcastreceiver;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Toast;
public class firstBroadReveiver extends BroadcastReceiver{
	@Override
	public void onReceive(Context context, Intent intent) {
		// TODO Auto-generated method stub
		String data=intent.getStringExtra("data");
		Toast.makeText(context, "我是firstBroadReveiver  "+data, Toast.LENGTH_LONG).show();
		//截断广播
		//abortBroadcast();
		Bundle bundle=new Bundle();
		bundle.putString("data1", "   增加这句话");
		setResultExtras(bundle);
	}
}

SecandBroadcastReceiver.java

package com.example.broadcastreceiver;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Toast;
public class SecandBroadReveiver extends BroadcastReceiver{
	@Override
	public void onReceive(Context context, Intent intent) {
		// TODO Auto-generated method stub
		String data=intent.getStringExtra("data");
		Bundle bundle=getResultExtras(false);
		String data1 =bundle.getString("data1");
		Toast.makeText(context, "我是SecandBroadReveiver"+data+data1, Toast.LENGTH_LONG).show();
	}

}