Service & Timer & Handler & leaked ServiceConnection

1 @Override
2     protected void onDestroy() {
3         super.onDestroy();
4         //在关闭Activity时取消与mService的绑定
5         unbindService(conn);        
6     }

 1 package com.rocky.myfirstserviceapp.service;
 2 
 3 import android.app.Service;
 4 import android.content.Intent;
 5 import android.os.Binder;
 6 import android.os.IBinder;
 7 
 8 public class MyService extends Service {
 9 
10     private int count = 0;
11     private boolean quit = false;
12     private MyBinder binder = new MyBinder();
13     
14     public class MyBinder extends Binder{
15         public int getNumber(){
16             //获取即时数值
17             return count;
18         }
19     }
20     
21     @Override
22     public IBinder onBind(Intent intent) {
23         System.out.println("Service is binded");
24         return binder; //返回IBinder实例
25     }
26     
27     @Override
28     public void onCreate() {
29         super.onCreate();
30         System.out.println("Service is Created");
31         
32         //新建一 个线程,每隔1秒加1
33         new Thread(){
34             public void run() {
35                 while(!false){
36                     try {
37                         Thread.sleep(1000);
38                     } catch (InterruptedException e) {
39                         e.printStackTrace();
40                     }
41                     count++;
42                 }
43             };
44         }.start();
45     }
46     
47     @Override
48     public boolean onUnbind(Intent intent) {
49         System.out.print("Service is Unbinded");
50         return true;
51     }
52     
53     @Override
54     public void onDestroy() {
55         super.onDestroy();
56         this.quit = true;
57         System.out.print("Service is destroyed");
58     }
59 
60 }

  1 package com.rocky.myfirstserviceapp;
  2 
  3 import java.util.Timer;
  4 import java.util.TimerTask;
  5 
  6 import com.rocky.myfirstserviceapp.service.MyService;
  7 import com.rocky.myfirstserviceapp.service.MyService.MyBinder;
  8 
  9 import android.app.Activity;
 10 import android.app.ActionBar;
 11 import android.app.Fragment;
 12 import android.app.Service;
 13 import android.content.ComponentName;
 14 import android.content.Intent;
 15 import android.content.ServiceConnection;
 16 import android.os.Bundle;
 17 import android.os.Handler;
 18 import android.os.IBinder;
 19 import android.os.Message;
 20 import android.view.LayoutInflater;
 21 import android.view.Menu;
 22 import android.view.MenuItem;
 23 import android.view.View;
 24 import android.view.ViewGroup;
 25 import android.widget.TextView;
 26 import android.widget.Toast;
 27 import android.os.Build;
 28 
 29 /**
 30  * 
 31  * @author LinXing 利后Service从1增加到100， 每秒加1。 多个Activity从Service中提取即时数值
 32  */
 33 
 34 public class MainActivity extends Activity {
 35 
 36     // 保存所启动的Service的IBinder对象
 37     private MyService.MyBinder mBinder;
 38     private TextView textView1;
 39 
 40     private ServiceConnection conn;
 41 
 42     // 接收信息后更新UI
 43     private Handler mHandler;
 44 
 45     private String mCount = "default";
 46 
 47     @Override
 48     protected void onCreate(Bundle savedInstanceState) {
 49         super.onCreate(savedInstanceState);
 50         setContentView(R.layout.activity_main);
 51 
 52         textView1 = (TextView) findViewById(R.id.textView1);
 53 
 54         // 创建启动Service的Intent
 55         Intent intent = new Intent(this, MyService.class);
 56  57 
 58         // 定义一个ServiceConnection对象
 59         conn = new ServiceConnection() {
 60 
 61             @Override
 62             public void onServiceDisconnected(ComponentName name) {
 63                 System.out.print("Service is disconnected");
 64             }
 65 
 66             @Override
 67             public void onServiceConnected(ComponentName name, IBinder service) {
 68                 mBinder = (MyService.MyBinder) service;
 69                 System.out.print("Service is connected");
 70             }
 71         };
 72 
 73         // 绑定service
 74         bindService(intent, conn, Service.BIND_AUTO_CREATE);
 75 
 76         // 实现Handler
 77         mHandler = new Handler() {
 78             @Override
 79             public void handleMessage(Message msg) {
 80                 super.handleMessage(msg);
 81 
 82                 if (msg.what == 0x33) {
 83                     if (mBinder != null) {   //**此处未加if判断语句就会出错，提示NullPointerException
 84                         // 获取Service中的实时Count值，并在UI中显示
 85                         mCount = mBinder.getNumber() + "";
 86                     }
 87 
 88                     // 在Toast中显示count
 89                     textView1.setText(mCount);
 90                 }
 91 
 92             }
 93         };
 94 
 95         // 计时器,每隔一秒发送一个消息
 96         new Timer().schedule(new TimerTask() {
 97 
 98             @Override
 99             public void run() {
100                 Message msg = new Message();
101                 msg.what = 0x33;
102                 mHandler.sendMessage(msg);
103             }
104         }, 0, 1000);
105 
106     }
107 
108     @Override
109     public boolean onCreateOptionsMenu(Menu menu) {
110 
111         // Inflate the menu; this adds items to the action bar if it is present.
112         getMenuInflater().inflate(R.menu.main, menu);
113         return true;
114     }
115 
116     @Override
117     public boolean onOptionsItemSelected(MenuItem item) {
118         // Handle action bar item clicks here. The action bar will
119         // automatically handle clicks on the Home/Up button, so long
120         // as you specify a parent activity in AndroidManifest.xml.
121         int id = item.getItemId();
122         if (id == R.id.action_settings) {
123             return true;
124         }
125         return super.onOptionsItemSelected(item);
126     }
127 
128 }