Android21_广播机制(二)

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1.在AndroidManifest.xml当中进行注册。

registerReceiver(receiver,filter);

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? ? ??取消注册BroadcastReceiver：

unregisterReceiver(receiver);

?如果一个BroadcastReceiver用于更新UI，那么通常会使用这种方法进行注册，在Activity启动的时候注册BroadcastReceiver，在Activity不可见以后取消注册。

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实例程序：

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BroadcastReceiverActivity02.java

package com.android.activity;import android.app.Activity;import android.content.IntentFilter;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class BroadcastReceiverActivity02 extends Activity {private static final String SMS_ACTION = "android.provider.Telephony.SMS_RECEIVED";private Button registerButton = null;private Button unregisterButton = null;private SMSReceiver smsReceiver = null;@Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        registerButton = (Button)findViewById(R.id.registerButton);        unregisterButton = (Button)findViewById(R.id.unregisterButton);        registerButton.setOnClickListener(new RegisterListener());        unregisterButton.setOnClickListener(new UnRegisterListener());    }class RegisterListener implements OnClickListener{public void onClick(View v) {//生成BroadcastReceiver对象smsReceiver = new SMSReceiver();//生成一个IntentFilter对象IntentFilter intentFilter = new IntentFilter();intentFilter.addAction(SMS_ACTION);//将BroadcastReceiver对象注册到系统中BroadcastReceiverActivity02.this.registerReceiver(smsReceiver, intentFilter);}}class UnRegisterListener implements OnClickListener{public void onClick(View v) {smsReceiver = new SMSReceiver();BroadcastReceiverActivity02.this.unregisterReceiver(smsReceiver);}}}

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SMSReceiver.java

package com.android.activity;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;public class SMSReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context arg0, Intent arg1) {System.out.println("receiver message");}}

?运行界面如下：

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当点击注册监听器时，就会将SMSReceiver注册。此时如果发送短信就会被其捕获。在Eclipse的DDMS视图下EmulatorControl标签下可以模拟短信发送。

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短信界面：

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?将接收的消息解析：

SMSReceiver.java

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package com.android.activity;import android.content.BroadcastReceiver;import android.content.Context;import android.content.Intent;import android.os.Bundle;import android.telephony.SmsMessage;public class SMSReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {System.out.println("receiver message");//将消息进行解析//接收Intent对象中的数据Bundle bundle  = intent.getExtras();//在Bundle对象中有一个属性pdus，这个属性的值是一个object数组Object[] objectPDUS = (Object[])bundle.get("pdus");//创建一个SmsMessage类型的数组SmsMessage[] messages = new SmsMessage[objectPDUS.length];for(int i = 0;i<objectPDUS.length;i++){//使用object数组当中的对象创建SmsMessage对象messages[i] = SmsMessage.createFromPdu((byte[])objectPDUS[i]);//调用SmsMessage对象的输出消息方法System.out.println(messages[i].getDisplayMessageBody());}}}