Android Service

 1 package com.newcj.test;
 2  
 3 import android.app.Service;
 4 import android.content.Intent;
 5 import android.os.IBinder;
 6  
 7 public class LocalService1 extends Service {
 8  
 9     /**
10      * onBind 是 Service 的虚方法，因此我们不得不实现它。
11      * 返回 null，表示客服端不能建立到此服务的连接。
12      */
13     @Override
14     public IBinder onBind(Intent intent) {
15         return null;
16     }
17      
18     @Override
19     public void onCreate() {
20         super.onCreate();
21     }
22      
23     @Override
24     public void onStart(Intent intent, int startId) {
25         super.onStart(intent, startId);
26     }
27      
28     @Override
29     public void onDestroy() {
30         super.onDestroy();
31     }
32  
33 }

1 // 启动一个 Activity
2 startActivity(new Intent(this, LocalService1.class));
3 ...
4 // 停止一个 Activity
5 stopService(new Intent(this, LocalService1.class));

 1 package com.newcj.test;
 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 LocalService extends Service {
 9  
10     /**
11      * 在 Local Service 中我们直接继承 Binder 而不是 IBinder,因为 Binder 实现了 IBinder 接口，这样我们可以少做很多工作。
12      * @author newcj
13      */
14     public class SimpleBinder extends Binder{
15         /**
16          * 获取 Service 实例
17          * @return
18          */
19         public LocalService getService(){
20             return LocalService.this;
21         }
22          
23         public int add(int a, int b){
24             return a + b;
25         }
26     }
27      
28     public SimpleBinder sBinder;
29      
30     @Override
31     public void onCreate() {
32         super.onCreate();
33         // 创建 SimpleBinder
34         sBinder = new SimpleBinder();
35     }
36      
37     @Override
38     public IBinder onBind(Intent intent) {
39         // 返回 SimpleBinder 对象
40         return sBinder;
41     }
42  
43 }

 1 package com.newcj.test;
 2  
 3 import android.app.Activity;
 4 import android.content.ComponentName;
 5 import android.content.Context;
 6 import android.content.Intent;
 7 import android.content.ServiceConnection;
 8 import android.os.Bundle;
 9 import android.os.IBinder;
10 import android.util.Log;
11 import android.view.View;
12 import android.view.View.OnClickListener;
13  
14 public class Main extends Activity {
15     private final static String TAG = "SERVICE_TEST";
16     private ServiceConnection sc;
17     private boolean isBind;
18  
19     @Override
20     public void onCreate(Bundle savedInstanceState) {
21         super.onCreate(savedInstanceState);
22         setContentView(R.layout.main);
23         sc = new ServiceConnection() {
24              
25             @Override
26             public void onServiceDisconnected(ComponentName name) {
27  
28             }
29              
30             @Override
31             public void onServiceConnected(ComponentName name, IBinder service) {
32                 LocalService.SimpleBinder sBinder = (LocalService.SimpleBinder)service;
33                 Log.v(TAG, "3 + 5 = " + sBinder.add(3, 5));
34                 Log.v(TAG, sBinder.getService().toString());
35             }
36         };
37         findViewById(R.id.btnBind).setOnClickListener(new OnClickListener() {
38              
39             @Override
40             public void onClick(View v) {
41                 bindService(new Intent(Main.this, LocalService.class), sc, Context.BIND_AUTO_CREATE);
42                 isBind = true;
43             }
44         });
45         findViewById(R.id.btnUnbind).setOnClickListener(new OnClickListener() {
46              
47             @Override
48             public void onClick(View v) {
49                 if(isBind){
50                     unbindService(sc);
51                     isBind = false;
52                 }
53             }
54         });
55     }
56 }

  1 package com.newcj.test;
  2  
  3 import java.lang.reflect.InvocationTargetException;
  4 import java.lang.reflect.Method;
  5  
  6 import android.app.Notification;
  7 import android.app.NotificationManager;
  8 import android.app.PendingIntent;
  9 import android.app.Service;
 10 import android.content.Context;
 11 import android.content.Intent;
 12 import android.os.IBinder;
 13  
 14 public class ForegroundService extends Service {
 15  
 16     private static final Class[] mStartForegroundSignature = new Class[] {
 17         int.class, Notification.class};
 18     private static final Class[] mStopForegroundSignature = new Class[] {
 19         boolean.class};
 20     private NotificationManager mNM;
 21     private Method mStartForeground;
 22     private Method mStopForeground;
 23     private Object[] mStartForegroundArgs = new Object[2];
 24     private Object[] mStopForegroundArgs = new Object[1];
 25      
 26     @Override
 27     public IBinder onBind(Intent intent) {
 28         return null;
 29     }
 30      
 31     @Override
 32     public void onCreate() {
 33         super.onCreate();
 34         mNM = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
 35         try {
 36             mStartForeground = ForegroundService.class.getMethod("startForeground", mStartForegroundSignature);
 37             mStopForeground = ForegroundService.class.getMethod("stopForeground", mStopForegroundSignature);
 38         } catch (NoSuchMethodException e) {
 39             mStartForeground = mStopForeground = null;
 40         }
 41          // 我们并不需要为 notification.flags 设置 FLAG_ONGOING_EVENT，因为
 42          // 前台服务的 notification.flags 总是默认包含了那个标志位
 43         Notification notification = new Notification(R.drawable.icon, "Foreground Service Started.",
 44                 System.currentTimeMillis());
 45         PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
 46                 new Intent(this, Main.class), 0);
 47         notification.setLatestEventInfo(this, "Foreground Service",
 48                 "Foreground Service Started.", contentIntent);
 49         // 注意使用  startForeground ，id 为 0 将不会显示 notification
 50         startForegroundCompat(1, notification);
 51     }
 52      
 53     @Override
 54     public void onDestroy() {
 55         super.onDestroy();
 56         stopForegroundCompat(1);
 57     }
 58      
 59     // 以兼容性方式开始前台服务
 60     private void startForegroundCompat(int id, Notification n){
 61         if(mStartForeground != null){
 62             mStartForegroundArgs[0] = id;
 63             mStartForegroundArgs[1] = n;
 64              
 65             try {
 66                 mStartForeground.invoke(this, mStartForegroundArgs);
 67             } catch (IllegalArgumentException e) {
 68                 e.printStackTrace();
 69             } catch (IllegalAccessException e) {
 70                 e.printStackTrace();
 71             } catch (InvocationTargetException e) {
 72                 e.printStackTrace();
 73             }
 74              
 75             return;
 76         }
 77         setForeground(true);
 78         mNM.notify(id, n);
 79     }
 80      
 81     // 以兼容性方式停止前台服务
 82     private void stopForegroundCompat(int id){
 83         if(mStopForeground != null){
 84             mStopForegroundArgs[0] = Boolean.TRUE;
 85              
 86             try {
 87                 mStopForeground.invoke(this, mStopForegroundArgs);
 88             } catch (IllegalArgumentException e) {
 89                 e.printStackTrace();
 90             } catch (IllegalAccessException e) {
 91                 e.printStackTrace();
 92             } catch (InvocationTargetException e) {
 93                 e.printStackTrace();
 94             }
 95             return;
 96         }
 97          
 98         //  在 setForeground 之前调用 cancel，因为我们有可能在取消前台服务之后
 99         //  的那一瞬间被kill掉。这个时候 notification 便永远不会从通知一栏移除
100         mNM.cancel(id);
101         setForeground(false);
102     }
103  
104 }