<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider
xmlns:android="http://schemas.android.com/apk/res/android"
  android:minWidth="300dp"
  android:minHeight="72dp"
  android:updatePeriodMillis="0"
  android:initialLayout="@layout/widget_ui"
>
</appwidget-provider>

public class MyWidgetProvider extends AppWidgetProvider {
  public static int Tag;
  public int max;
  public int current;
  @Override
  public void onEnabled(Context context) {
    super.onEnabled(context);
    System.out.println("第一次被创建时调用这个方法");
  }
  @Override
  public void onDisabled(Context context) {
    System.out.println("当最后一个App Widget被删除时调用该方法");
  }
  @Override
  public void onReceive(Context context, Intent intent) {
  //调用父类的onReceive方法不能少，否则就无法监听到onUpdate事件了
    super.onReceive(context, intent);
    System.out.println("接收广播事件");
  }
  @Override
  public void onUpdate(Context context, AppWidgetManager appWidgetManager,
      int[] appWidgetIds) {
      System.out.println("在到达指定的更新时间之后或者当用户向桌面添加App Widget时调用这个方法");
      for(int i = 0; i < appWidgetIds.length; i++){
        Intent intent = new Intent(context, HB.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);
        //R.layout.widget_ui指的是显示在桌面上的控件布局
        RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget_ui);
        //R.id.widgetButton指的是为桌面控件按钮绑定事件
        remoteViews.setOnClickPendingIntent(R.id.widgetButton, pendingIntent);
        //updateAppWidget方法更新remoteViews
        appWidgetManager.updateAppWidget(appWidgetIds[i], remoteViews);
      }
    }
  }
  @Override
  public void onDeleted(Context context, int[] appWidgetIds){
    System.out.println("App Widget被删除时调用这个方法");
  }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content">
  <Button
  android:id="@+id/widget_BT_Up"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_weight="1"
  android:text="Value++"/>
  <Button android:id="@+id/widget_BT_Down"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:text="Value--"
  android:layout_weight="1"/>
</LinearLayout>

<receiver android:name=".MyWidgetProvider" android:label="myWIdget" android:icon="@drawable/icon">
  <intent-filter>
    <action android:name="android.appwidget.action.APPWIDGET_UPDATE"/>
  </intent-filter>
  <meta-data android:name="android.appwidget.provider" android:resource="@xml/widget_config"/>
</receiver>