通过ip拨号器来了解广播接收者

1、继承广播接收者类

 package com.example.ipdail;

 import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;

 public class OutCallReceiver extends BroadcastReceiver {

     @Override
     public void onReceive(Context context, Intent intent) {
         // TODO Auto-generated method stub
         //获取拨打的号码
         String number = getResultData();
         //获取config数据里面的数据
         SharedPreferences sp = context.getSharedPreferences("config", context.MODE_PRIVATE);
         String ipnumber = sp.getString("ipnumber", "");

         //修改号码并返回
         String newNumber = ipnumber + number;
         setResultData(newNumber);
     }

 }

2、在清单文件配置广播接收者(因为属于四大组件之一),并通过action来表名要监听的频道

  <receiver android:name=".OutCallReceiver">
             <intent-filter>
                 <action android:name="android.intent.action.NEW_OUTGOING_CALL"></action>
             </intent-filter>
         </receiver>

3、由于要监听外拨电话，所以要加一个权限

 <uses-permission android:name="android.permission.PROCESS_OUTGOING_CALLS"/>

4、其他java代码

 package com.example.ipdail;

 import android.os.Bundle;
 import android.app.Activity;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.Editor;
 import android.view.Menu;
 import android.view.View;
 import android.widget.EditText;

 public class MainActivity extends Activity {

     private EditText et_ipnumber;

     private SharedPreferences sp;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         et_ipnumber = (EditText)findViewById(R.id.et_ipnumber);
         sp = getSharedPreferences("config", MODE_PRIVATE);
         et_ipnumber.setText(sp.getString("ipnumber", ""));
     }

     public void click(View view){
         String ipnumber = et_ipnumber.getText().toString().trim();

         Editor editor = sp.edit();
         editor.putString("ipnumber", ipnumber);
         editor.commit();
     }
 }