如何自动推进ListView应用程序小部件,如Honeycomb上的StackView应用程序小部件？

Question

我正在寻找一种方法来定期动画/自动推进ListView应用程序小部件,就像使用StackView应用程序小部件一样.

例如,Android Market和YouTube小部件通过自动前进到集合中的下一个项目(在Honeycomb上)每20秒进行一次动画制作.

我在StackView Widget示例中看到他们对StackView小部件使用autoAdvanceViewId设置:

<appwidget-provider
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:minWidth="150dip"
  android:minHeight="150dip"
  android:updatePeriodMillis="3600000"
  android:previewImage="@drawable/preview"
  android:initialLayout="@layout/widget_layout"
  android:autoAdvanceViewId="@id/stack_view">
</appwidget-provider>

是否可以以某种方式为ListView应用程序小部件完成或模拟？

非常感谢,
劳伦特

Answer 1

我找到了一个解决方案,但它可能不太理想!

我在AppWidgetProvider的onEnable()中设置了一个重复警报,并在onDisabled()中取消它.该警报触发BroadcastReceiver,它更新窗口小部件视图并在RemoteView上使用setRelativeScrollPosition().

这里有几行代码:

• 在扩展AppWidgetProvider的类中

  public void onEnabled(Context context) {
      [...]
    // create alarm that will move the widget list content every n seconds
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
  
    long firstTime = SystemClock.elapsedRealtime();
    firstTime += 10*1000;
  
    Intent i = new Intent(context, WidgetAutoScroller.class);
    PendingIntent widgetAutoScroll = PendingIntent.getBroadcast(context, 0, i, 0);
    alarmManager.setInexactRepeating(AlarmManager.ELAPSED_REALTIME, firstTime, 
          10*1000, widgetAutoScroll);
    super.onEnabled(context);
  }
  
  @Override
  public void onDisabled(Context context) {
    // deactivate the alarm that moves the widget content 
    Intent i = new Intent(context, WidgetAutoScroller.class);
    PendingIntent widgetAutoScroll = PendingIntent.getBroadcast(context, 0, i, 0);
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    alarmManager.cancel(widgetAutoScroll);
    super.onDisabled(context);
  }
  

• WidgetAutoScroller.java

public class WidgetAutoScroller extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
        int[] appWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, CascadeWidgetProvider.class));

        for( int i=0 ; i<appWidgetIds.length ; i++) {
            int appWidgetId = appWidgetIds[i];
            RemoteViews rv = CascadeWidgetProvider.getWidgetView(context, appWidgetId);
            rv.setRelativeScrollPosition(R.id.widget_collection, 1);
            appWidgetManager.updateAppWidget(appWidgetId, rv);
        }
    }
}

public class WidgetAutoScroller extends BroadcastReceiver {

public void onEnabled(Context context) {
    [...]
  // create alarm that will move the widget list content every n seconds
  AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);

  long firstTime = SystemClock.elapsedRealtime();
  firstTime += 10*1000;

  Intent i = new Intent(context, WidgetAutoScroller.class);
  PendingIntent widgetAutoScroll = PendingIntent.getBroadcast(context, 0, i, 0);
  alarmManager.setInexactRepeating(AlarmManager.ELAPSED_REALTIME, firstTime, 
        10*1000, widgetAutoScroll);
  super.onEnabled(context);
}

@Override
public void onDisabled(Context context) {
  // deactivate the alarm that moves the widget content 
  Intent i = new Intent(context, WidgetAutoScroller.class);
  PendingIntent widgetAutoScroll = PendingIntent.getBroadcast(context, 0, i, 0);
  AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
  alarmManager.cancel(widgetAutoScroll);
  super.onDisabled(context);
}

如果您对我的问题有更好的解决方案,请回答.

编辑:另一个问题是:当我到达列表末尾时该怎么办？
我想转到列表的第一项,但我不知道如何从我的RemoteView或appWidgetId获取列表的当前位置...