AppWidget3

Xml代码  

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

 

 

Java代码  

1. public class BatteryWidget extends AppWidgetProvider {  
2.   
3.     public void onUpdate(Context context, AppWidgetManager appWidgetManager,  
4.             int[] appWidgetIds) {  
5.         super.onUpdate(context, appWidgetManager, appWidgetIds);  
6.         Intent intent = new Intent(context, AppBatteryService.class);  
7.         context.startService(intent);// 不是context.startActivity(intent);  
8.     }  
9.   
10.     /* UpdateService系统服务后台运行 */  
11.     public static class AppBatteryService extends Service {//不要忘记static 否则会抛出Unable to instantiate service异常  
12.         private UpdateReceiver receiver;  
13.   
14.         public IBinder onBind(Intent arg0) {  
15.             return null;  
16.         }  
17.   
18.         public void onStart(Intent intent, int startId) {  
19.             super.onStart(intent, startId);  
20.   
21.             IntentFilter filter = new IntentFilter(  
22.                     Intent.ACTION_BATTERY_CHANGED);  
23.             receiver = new UpdateReceiver();  
24.             registerReceiver(receiver, filter);  
25.   
26.             RemoteViews updateViews = getRemoteViews(this);  
27.             /* 建立ComponentName对象与AppWidgetManager对象 */  
28.             ComponentName thisWidget = new ComponentName(this,  
29.                     BatteryWidget.class);  
30.             AppWidgetManager manager = AppWidgetManager.getInstance(this);  
31.             manager.updateAppWidget(thisWidget, updateViews);  
32.         }  
33.   
34.         public void onDestroy() {  
35.             unregisterReceiver(receiver);  
36.             super.onDestroy();  
37.         }  
38.   
39.         public RemoteViews getRemoteViews(Context context) {  
40.             RemoteViews retRemoteViews = null;  
41.             retRemoteViews = new RemoteViews(context.getPackageName(),  
42.                     R.layout.update_widget);  
43.             /* 取得保存在SharedPreferences的电量值 */  
44.             int power = 0;  
45.             SharedPreferences pres = context.getSharedPreferences("battery",  
46.                     Context.MODE_PRIVATE);  
47.             if (pres != null) {  
48.                 power = pres.getInt("power", 0);  
49.             }  
50.             /* 更新电量文字显示 */  
51.             retRemoteViews.setTextViewText(R.id.myTextView1, power + "%");  
52.             /* 更新电量图形显示 */  
53.             if (power != 0) {  
54.                 Bitmap bmp = BitmapFactory.decodeResource(  
55.                         context.getResources(), R.drawable.power);  
56.   
57.                 float x = 57.0f / 100 * power;  
58.                 Matrix matrix = new Matrix();  
59.                 matrix.postScale(x, 1.0f);  
60.                 Bitmap resizeBmp = Bitmap.createBitmap(bmp, 0, 0, 1, 39,  
61.                         matrix, true);  
62.   
63.                 retRemoteViews.setBitmap(R.id.myImageView1,  
64.   
65.                 "setImageBitmap", resizeBmp);  
66.             }  
67.             return retRemoteViews;  
68.         }  
69.   
70.         public class UpdateReceiver extends BroadcastReceiver {  
71.   
72.             public void onReceive(Context context, Intent intent) {  
73.   
74.                 if (intent.getAction().equals  
75.   
76.                 (Intent.ACTION_BATTERY_CHANGED)) {  
77.   
78.                     int intLevel = intent.getIntExtra("level", 0);  
79.                     int intScale = intent.getIntExtra("scale", 100);  
80.                     /* 将电量保存在SharedPreferences中 */  
81.                     SharedPreferences pres =  
82.   
83.                     context.getSharedPreferences("battery",  
84.                             Context.MODE_PRIVATE);  
85.                     if (pres != null) {  
86.                         SharedPreferences.Editor ed = pres.edit();  
87.                         ed.putInt("power", (intLevel * 100 /  
88.   
89.                         intScale));  
90.                         ed.commit();  
91.                     }  
92.                 }  
93.             }  
94.   
95.         }  
96.     }  
97.   
98. }  

 manifest.xml

 

Xml代码  

1. <receiver  
2.             android:name=".BatteryWidget"  
3.             android:label="@string/app_name">  
4.             <intent-filter>  
5.                 <action  
6.                     android:name="android.appwidget.action.APPWIDGET_UPDATE" />  
7.             </intent-filter>  
8.             <meta-data  
9.                 android:name="android.appwidget.provider"  
10.                 android:resource="@xml/widget_template" />  
11.         </receiver>  
12.         <service  
13.             android:name=".BatteryWidget$AppBatteryService" />  

 widget_template.xml

 

Xml代码  

1. <?xml version="1.0" encoding="utf-8"?>   
2. <appwidget-provider  
3.   xmlns:android="http://schemas.android.com/apk/res/android"  
4.   android:minWidth="72dip"   
5.   android:minHeight="72dip"   
6.   android:updatePeriodMillis="10000"   
7.   android:initialLayout="@layout/update_widget"   
8. />  

 update_widget.xml

 

Xml代码  

1. <?xml version="1.0" encoding="utf-8"?>  
2. <RelativeLayout  
3.     xmlns:android="http://schemas.android.com/apk/res/android"  
4.     android:background="@drawable/batt"  
5.     android:orientation="vertical"  
6.     android:layout_width="72dip"  
7.     android:layout_height="72dip">  
8.     <ImageView  
9.         android:id="@+id/myImageView1"  
10.         android:layout_width="wrap_content"  
11.         android:layout_height="wrap_content"  
12.         android:layout_gravity="center"  
13.         android:layout_marginLeft="5dip"  
14.         android:layout_marginTop="6dip" />  
15.     <TextView  
16.         android:id="@+id/myTextView1"  
17.         android:layout_width="fill_parent"  
18.         android:layout_height="wrap_content"  
19.         android:layout_x="24px"  
20.         android:layout_y="22px"  
21.         android:layout_marginTop="44dip"  
22.         android:gravity="center_horizontal" />  
23. </RelativeLayout>