监听电话状态

请看程序
PhoneActivity.java

package com.phone;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;

public class PhoneActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        init();
    }
    
    private void init(){
    	TelephonyManager telManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
    	//通过电话管理器监听通话状态(回调机制)
    	telManager.listen(new PhoneStateListener(){
      	  	public void onCallStateChanged(int state,String incomingNumber){
      	  		System.out.println("state:"+state);
      	  		switch(state){
        	      /*TelephonyManager.CALL_STATE_IDLE://空闲
        	      TelephonyManager.CALL_STATE_OFFHOOK://接起电话
        	      TelephonyManager.CALL_STATE_RINGING://振铃*/
      	  		case TelephonyManager.CALL_STATE_IDLE:
      	  			System.out.println("空闲");
      	  			break;
      	  		case TelephonyManager.CALL_STATE_OFFHOOK:
      	  			System.out.println("接起电话");
      	  			break;
      	  		case TelephonyManager.CALL_STATE_RINGING:
      	  			System.out.println("振铃");
      	  			break;
      	  		default:
      	  			System.out.println("其他");
        	  	}
      	  	}
    	},PhoneStateListener.LISTEN_CALL_STATE);
    }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.recorder"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="8" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
        <activity
            android:label="@string/app_name"
            android:name=".RecorderActivity" >
            <intent-filter >
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
	<uses-permission android:name="android.permission.RECORD_AUDIO"></uses-permission>  
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
</manifest>