刷新小部件上的现有数据

Question

我正在为Android实现新闻小部件。在onUpdate中，我正在获取所有数据（大约50篇文章，其中包含一些文本和url）。我希望实现左右按钮在新闻之间循环。但是onReceive我只能调用onUpdate，并且onUpdate将再次获取所有项目。如何实现左键和右键单击而又不使用现有数据又重新获取所有数据。还有另一个问题，如果我在AppWidgetProvider中定义了全局变量，它是不是在某个时候被垃圾收集器收集了，或者它永远与小部件“共存”？

代码：

public class MyWidgetProvider extends AppWidgetProvider {
    private static final String RIGHT_CLICKED = "RIGHT_CLICKED";
    private static final String LEFT_CLICKED = "LEF_CLICKED";

    @Override
    public void onReceive(Context context, Intent intent) {
        super.onReceive(context, intent);

        if (RIGHT_CLICKED.equals(intent.getAction())) {

           //Get next content on list
        }

        if (LEFT_CLICKED.equals(intent.getAction())) {

            //Get prev content on list
        }

    }

    @Override
    public void onUpdate(final Context context, final AppWidgetManager appWidgetManager, int[] appWidgetIds) {

        //Fetching all stories from RSS
        RSSFetchCallback rssFetchCallback = new RSSFetchCallback() {
            @Override
            public void onComplete(ArrayList<Story> stories) {


                ComponentName thisWidget = new ComponentName(context, MyWidgetProvider.class);
                int[] allWidgetIds = appWidgetManager.getAppWidgetIds(thisWidget);

                for (int widgetId : allWidgetIds) {

                    RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.appwidget);
                    remoteViews.setTextViewText(R.id.textViewContent, stories.get(0).getContent()); //Setting 0 story for example
                    remoteViews.setTextViewText(R.id.textViewHeadline, stories.get(0).getTitle());  //Setting 0 story for example


                    remoteViews.setOnClickPendingIntent(R.id.buttonRight, getPendingSelfIntent(context, RIGHT_CLICKED));
                    remoteViews.setOnClickPendingIntent(R.id.buttonLeft, getPendingSelfIntent(context, LEFT_CLICKED));
                    appWidgetManager.updateAppWidget(widgetId, remoteViews);


                    //Loading R.id.imageView with Glide
                    AppWidgetTarget awt = new AppWidgetTarget(context, R.id.imageView, remoteViews, widgetId) {
                        @Override
                        public void onResourceReady(Bitmap resource, Transition<? super Bitmap> transition) {
                            super.onResourceReady(resource, transition);
                        }
                    };

                    RequestOptions options = new RequestOptions().override(300, 300).placeholder(R.mipmap.ic_launcher).error(R.mipmap.ic_launcher);


                    Glide.with(context.getApplicationContext())
                            .asBitmap()
                            .load(stories.get(0).getImgUrl())//Setting 0 story image for example
                            .apply(options)
                            .into(awt);
                    //End Loading R.id.imageView with Glide
                }
            }



        };

        RSSFetcher.getData(rssFetchCallback);

    }

    protected PendingIntent getPendingSelfIntent(Context context, String action) {
        Intent intent = new Intent(context, getClass());
        intent.setAction(action);
        return PendingIntent.getBroadcast(context, 0, intent, 0);
    }
}