Android提高第六篇之BroadcastReceiver

最后更新于:2022-04-01 15:46:54

本文来自[http://blog.csdn.net/hellogv/](http://blog.csdn.net/hellogv/) ,引用必须注明出处!        前面分别讨论了[Activity](http://blog.csdn.net/hellogv/archive/2010/11/06/5992198.aspx)和[Service](http://blog.csdn.net/hellogv/archive/2010/11/08/5994952.aspx),这次就轮到BroastcastReceiver,Broastcast是应用程序间通信的手段。BroastcastReceiver也是跟Intent紧密相连的,动态/静态注册了BroastcastReceiver之后,使用sendBroadcast把Intent发送之后,系统会自动把符合条件的BroastcastReceiver启动,跟嵌入式系统的中断类似。         本文主要演示了如何静态/动态注册BroastcastReceiver,向系统索取电量信息,以及枚举信息的字段。本文运行截图如下: ![](https://docs.gechiui.com/gc-content/uploads/sites/kancloud/2016-06-24_576cb09f2503e.gif) ![](https://docs.gechiui.com/gc-content/uploads/sites/kancloud/2016-06-24_576cb09f3a41d.gif) 上图是发送Intent至内部动态注册的BroadcastReceiver,接收到之后显示消息名称。动态注册BroadcastReceiver用到registerReceiver()。   ![](https://docs.gechiui.com/gc-content/uploads/sites/kancloud/2016-06-24_576cb09f4b897.gif) 上图是发送Intent至内部静态注册的BroadcastReceiver,接收到之后显示消息名称。静态注册比动态注册麻烦点,先新建一个类继承BroadcastReceiver,然后到AndroidManifest.xml 添加 ~~~ <receiver android:name="clsReceiver2"> <intent-filter> <action android:name="com.testBroadcastReceiver.Internal_2"/> </intent-filter> </receiver> ~~~ 第一个name是类名,第二个是action的名称。 ![](https://docs.gechiui.com/gc-content/uploads/sites/kancloud/2016-06-24_576cb09f5e219.gif) 上图是枚举Intent消息的字段,这个功能比较适合懒人,把收到的Intent消息的字段全部分解了,再看看哪个需要的,懒得记住。实现这部分的代码如下: //当未知Intent包含的内容,则需要通过以下方法来列举 Bundle b=intent.getExtras(); Object[] lstName=b.keySet().toArray(); for(int i=0;i<lstName.length;i++) { String keyName=lstName[i].toString(); Log.e(keyName,String.valueOf(b.get(keyName))); } main.xml的代码如下: ~~~ <?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <Button android:id="@+id/Button01" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="发送至内部动态注册的BroadcastReceiver"></Button> <Button android:id="@+id/Button02" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="发送至内部静态注册BroadcastReceiver"></Button> <Button android:id="@+id/Button03" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="发送至系统BroadcastReceiver"></Button></LinearLayout> ~~~ testBroadcastReceiver.java的代码如下: ~~~ package com.testBroadcastReceiver;import android.app.Activity;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.content.IntentFilter;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.Toast;public class testBroadcastReceiver extends Activity { Button btnInternal1,btnInternal2,btnSystem; static final String INTENAL_ACTION_1 = "com.testBroadcastReceiver.Internal_1"; static final String INTENAL_ACTION_2 = "com.testBroadcastReceiver.Internal_2"; static final String INTENAL_ACTION_3 = "com.testBroadcastReceiver.Internal_3"; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); btnInternal1=(Button)this.findViewById(R.id.Button01); btnInternal1.setOnClickListener(new ClickEvent()); btnInternal2=(Button)this.findViewById(R.id.Button02); btnInternal2.setOnClickListener(new ClickEvent()); btnSystem=(Button)this.findViewById(R.id.Button03); btnSystem.setOnClickListener(new ClickEvent()); //动态注册广播消息 registerReceiver(bcrIntenal1, new IntentFilter(INTENAL_ACTION_1)); } class ClickEvent implements View.OnClickListener{ @Override public void onClick(View v) { if(v==btnInternal1)//给动态注册的BroadcastReceiver发送数据 { Intent intent = new Intent(INTENAL_ACTION_1); sendBroadcast(intent); } else if(v==btnInternal2)//给静态注册的BroadcastReceiver发送数据 { Intent intent = new Intent(INTENAL_ACTION_2); sendBroadcast(intent); } else if(v==btnSystem)//动态注册 接收2组信息的BroadcastReceiver { IntentFilter filter = new IntentFilter();// filter.addAction(Intent.ACTION_BATTERY_CHANGED);//系统电量检测信息 filter.addAction(INTENAL_ACTION_3);//第三组自定义消息 registerReceiver(batInfoReceiver, filter); Intent intent = new Intent(INTENAL_ACTION_3); intent.putExtra("Name", "hellogv"); intent.putExtra("Blog", "http://blog.csdn.net/hellogv"); sendBroadcast(intent);//传递过去 } } } /* * 接收动态注册广播的BroadcastReceiver */ private BroadcastReceiver bcrIntenal1 = new BroadcastReceiver() { public void onReceive(Context context, Intent intent) { String action = intent.getAction(); Toast.makeText(context, "动态:"+action, 1000).show(); } }; private BroadcastReceiver batInfoReceiver = new BroadcastReceiver() { public void onReceive(Context context, Intent intent) { String action = intent.getAction(); //如果捕捉到的action是ACTION_BATTERY_CHANGED if (Intent.ACTION_BATTERY_CHANGED.equals(action)) { //当未知Intent包含的内容,则需要通过以下方法来列举 Bundle b=intent.getExtras(); Object[] lstName=b.keySet().toArray(); for(int i=0;i<lstName.length;i++) { String keyName=lstName[i].toString(); Log.e(keyName,String.valueOf(b.get(keyName))); } } //如果捕捉到的action是INTENAL_ACTION_3 if (INTENAL_ACTION_3.equals(action)) { //当未知Intent包含的内容,则需要通过以下方法来列举 Bundle b=intent.getExtras(); Object[] lstName=b.keySet().toArray(); for(int i=0;i<lstName.length;i++) { String keyName=lstName[i].toString(); Log.e(keyName,b.getString(keyName)); } } } };} ~~~ clsReceiver2.java的代码如下: ~~~ package com.testBroadcastReceiver;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.widget.Toast;/* * 接收静态注册广播的BroadcastReceiver, * step1:要到AndroidManifest.xml这里注册消息 * <receiver android:name="clsReceiver2"> <intent-filter> <action android:name="com.testBroadcastReceiver.Internal_2"/> </intent-filter> </receiver> step2:定义消息的字符串 step3:通过Intent传递消息来驱使BroadcastReceiver触发 */public class clsReceiver2 extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { String action = intent.getAction(); Toast.makeText(context, "静态:"+action, 1000).show(); }} ~~~
';