拦截电话

广播接受者创建

1创建广播接收者（买了一台收音机）
2 注册广播接收者
3 添加过滤器(添加频道）
4 添加权限

1创建广播接收者 2注册广播接收者

new -other -broadcastreceiver
添加广播接收者名称例如MyTelephoneReceiver
完成后会产生一个MyTelephoneReceiver的类，并且在AndroidMainifest文件中注册。
MyTelephoneReceiver类

public class MyTelephoneReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
    // TODO: This method is called when the BroadcastReceiver is receiving
    //当接收了广播之后会调用该方法
}
}

AndroidMainifest.xml文件

  <receiver
        android:name=".MyTelephoneReceiver"
        android:enabled="true"
        android:exported="true">
      </intent-filter>
    </receiver>

3 添加过滤器 4 添加权限

想要接受外拨电话的系统广播就要添加外拨电话的过滤器
在AndroidMainifest.xml文件中添加过滤器，并添加权限

<receiver
        android:name=".MyTelephoneReceiver"
        android:enabled="true"
        android:exported="true">
      <intent-filter>
          <action android:name="android.intent.action.NEW_OUTGOING_CALL"/>
      </intent-filter>
    </receiver>


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

5 接收到广播后，判断号码并拦截

在MyTelephoneReceiver类中添加代码

public class MyTelephoneReceiver extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {
    // TODO: This method is called when the BroadcastReceiver is receiving
    //当接收了广播之后会调用该方法
    String number=getResultData();//获取号码
    Log.i("mybroadcastreceiver","我监听到了有人向外拨打电话"+number);
    if(number.equals("13312345678")){
        setResultData(null);
    }
}
}