Android Widget示例

Widget并不支持所有的Android组件，只能在Widget中使用如下组件类：

1)用于布局的组件类。

FrameLayout   LinearLayout 　　RelativeLayout

2)可视组件类

AnalogClock  ImageView   ProgressBar   TextView   Button  Chronometer  ImageButton



view sourceprint?
1 创建Widget描述文件，该文件是Xml格式，必须放在res\xml目录中 

2 <?xml version="1.0" encoding="utf-8"?> 

3 <appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"

4     android:minWidth="309dip"

5     android:minHeight="192dip"

6     android:initialLayout="@layout/main"    初始化布局 

7     android:updatePeriodMillis="1000"       更新的时间间隔(毫秒) 

8 />
view sourceprint?
1 建立Widget类，该类必须从AppWidgetProvider类继承(AppWidgetProvider是BroadcastReceiver的子类，因此，Widget类可以接受广播消息) 

2 在AndroidManifest.xml文件中定义widget 

3 <receiver android:label="@string/app_name" android:name=".HelloWidget"> 

4             <intent-filter> 

5                 <action android:name="android.appwidget.action.APPWIDGET_UPDATE"/> 

6             </intent-filter> 

7             <meta-data android:name="android.appwidget.provider"

8                 android:resource="@xml/hello_widget_provider"/> 

9 </receiver>


view sourceprint?
01 显示时间，每秒更新 

02 public class HelloWidget extends AppWidgetProvider { 

03     private Timer timer; 

04     private int[] appWidgetIds; 

05     private AppWidgetManager appWidgetManager; 

06     private Context context; 

07       

08     @Override

09     public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { 

10         super.onUpdate(context, appWidgetManager, appWidgetIds); 

11         Log.i("Widget", "onUpdate"); 

12         this.context = context; 

13         this.appWidgetManager = appWidgetManager; 

14         this.appWidgetIds = appWidgetIds; 

15         timer = new Timer(); 

16         timer.schedule(task, 0,1000); 

17 } 

18     private Handler handler = new Handler(){ 

19         @Override

20         public void handleMessage(Message msg) { 

21             super.handleMessage(msg); 

22             switch (msg.what) { 

23             case 1: 

24                 Time myTime = new Time(); 

25                 myTime.setToNow(); 

26                 RemoteViews updateViews =  

27                     new RemoteViews(context.getPackageName(), 

28                       R.layout.main); 

29                 updateViews.setTextViewText(R.id.widget_textview, "北京时间"+myTime.format("%H:%M:%S")); 

30                 Log.i("Widget", "北京时间"+myTime.format("%H:%M:%S")); 

31 //              ComponentName thisWidget = new ComponentName(context,HelloWidget.class); 

32 //              appWidgetManager.updateAppWidget(thisWidget, updateViews); 

33                 appWidgetManager.updateAppWidget(appWidgetIds, updateViews); 

34                 break; 

35             default: 

36                 break; 

37             } 

38         } 

39     }; 

40     private TimerTask task = new TimerTask() { 

41         public void run() { 

42             handler.sendEmptyMessage(1); 

43         } 

44     }; 

45 }
音乐播放widget

view sourceprint?01 package cn.stay.widget; 

02   

03 import android.app.PendingIntent; 

04 import android.appwidget.AppWidgetManager; 

05 import android.appwidget.AppWidgetProvider; 

06 import android.content.Context; 

07 import android.content.Intent; 

08 import android.os.Handler; 

09 import android.os.Message; 

10 import android.widget.RemoteViews; 

11 import cn.aoran.activity.R; 

12   

13 public class HelloWidget extends AppWidgetProvider { 

14     private static final String WIDGET_BACK = "cn.stay.widget.back"; 

15     private static final String WIDGET_PLAY = "cn.stay.widget.play"; 

16     private static final String WIDGET_NEXT = "cn.stay.widget.next"; 

17     private static final String WIDGET_SONG = "cn.stay.widget.song"; 

18     private static final String WIDGET_CURRENT = "cn.stay.widget.current"; 

19     private String song = ""; 

20     private static Context context; 

21     private static AppWidgetManager appWidgetManager; 

22     private static int[] appWidgetIds; 

23   

24     @Override

25     public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { 

26         super.onUpdate(context, appWidgetManager, appWidgetIds); 

27         HelloWidget.context = context; 

28         HelloWidget.appWidgetIds = appWidgetIds; 

29         HelloWidget.appWidgetManager = appWidgetManager; 

30         handler.sendEmptyMessage(0); 

31     } 

32   

33     @Override

34     public void onReceive(Context context, Intent intent) { 

35         super.onReceive(context, intent); 

36         if (WIDGET_SONG.equals(intent.getAction())) { 

37             song = intent.getStringExtra("song"); 

38             if (song == null || "".equals(song.trim())) { 

39                 song = "未知"; 

40             } 

41             if (context != null) { 

42                 handler.sendEmptyMessage(1); 

43             } 

44         } 

45     } 

46   

47     private Handler handler = new Handler() { 

48         public void handleMessage(Message msg) { 

49             RemoteViews widgetViews = new RemoteViews(context.getPackageName(), R.layout.widget_layout); 

50             super.handleMessage(msg); 

51             switch (msg.what) { 

52             case 0: 

53                 context.sendBroadcast(new Intent(WIDGET_CURRENT)); 

54                 // Intent intent = new Intent(context,LocalActivity.class); 

55                 // PendingIntent pIntent = PendingIntent.getActivity(context, 0, intent, 0); 

56                 // widgetViews.setOnClickPendingIntent(R.id.widget_sub, pIntent); 

57                 // 上一首 

58                 PendingIntent backIntent = PendingIntent.getBroadcast(context, 0, new Intent(WIDGET_BACK), 0); 

59                 widgetViews.setOnClickPendingIntent(R.id.widget_back_btn, backIntent); 

60                 // 下一首 

61                 PendingIntent nextIntent = PendingIntent.getBroadcast(context, 0, new Intent(WIDGET_NEXT), 0); 

62                 widgetViews.setOnClickPendingIntent(R.id.widget_next_btn, nextIntent); 

63                 // 播放 

64                 PendingIntent playIntent = PendingIntent.getBroadcast(context, 0, new Intent(WIDGET_PLAY), 0); 

65                 widgetViews.setOnClickPendingIntent(R.id.widget_play_btn, playIntent); 

66   

67                 appWidgetManager.updateAppWidget(appWidgetIds, widgetViews); 

68                 break; 

69             case 1: 

70                 widgetViews.setTextViewText(R.id.widget_song, song); 

71 //              ComponentName thisWidget = new ComponentName(context, HelloWidget.class); 

72 //              AppWidgetManager manager = AppWidgetManager.getInstance(context); 

73                 appWidgetManager.updateAppWidget(appWidgetIds, widgetViews); 

74                 break; 

75             default: 

76                 break; 

77             } 

78         } 

79   

80     }; 

81 }