带有 ListView 的 Android Widget 仅显示加载 View

Question

我正在尝试实现一个带有 ListView 的 Android App Widget。我开始遵循 Google 文档，但我被正在显示的加载 View 列表而不是正常的列表项卡住了。有人有使用小部件中的 ListView 的经验吗？

代码与Google docs中的相同.我使用 ListView 而不是 StackView 作为数据源，我使用数据库(这不是问题，数据是正确获取的 - 我已经尝试通过返回具有正确数据的普通列表项 View 而不是默认加载 View )

在互联网上搜索对我没有帮助...我也尝试了这个 tutorial但它也没有用。我希望任何人都可以帮助我，在此先感谢!

代码

WidgetProvider.java

public class WidgetProvider extends AppWidgetProvider {

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

        for (int i = 0; i < appWidgetIds.length; i++) {

            Intent intent = new Intent(context, EventWidgetService.class);
            intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetIds[i]);
            intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME)));

            RemoteViews rv = new RemoteViews(context.getPackageName(), R.layout.widget);
            rv.setRemoteAdapter(android.R.id.list, intent);
            rv.setEmptyView(android.R.id.list, R.id.tvEmptyList);

            appWidgetManager.updateAppWidget(appWidgetIds[i], rv);
        }

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

WidgetService.java

public class EventWidgetService extends RemoteViewsService {

    @Override
    public RemoteViewsFactory onGetViewFactory(Intent intent) {

         return new EventsWidgetListProvider(getApplicationContext(), intent);
    }
}

WidgetListProvider

public class EventsWidgetListProvider implements RemoteViewsFactory {

    private List<> _entities = new ArrayList<>();
    private Context _context;
//  private int _appWidgetId;

    public EventsWidgetListProvider(Context context, Intent intent) {

        _context = context;
//      _appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
    }

    @Override
    public void onCreate() { }

    private void refreshEntities() {

        // Request data from database
        _entities = RequestResult;
    }

    @Override
    public RemoteViews getViewAt(int position) {

        final RemoteViews remoteViews = new RemoteViews(_context.getPackageName(), R.layout.list_row);

        // Set data to remoteViews [remoteViews.setTextViewText(), remoteViews.setImageViewResource()]

        return remoteViews;
    }

    @Override
    public int getCount() {

        return _entities.size();
    }

    @Override
    public long getItemId(int position) {

        return position;
    }

    @Override
    public void onDataSetChanged() {

        refreshEntities();
    }

    @Override
    public void onDestroy() { }

    @Override
    public RemoteViews getLoadingView() {

        return new RemoteViews(_context.getPackageName(), R.layout.widget_loading);
    }

    @Override
    public int getViewTypeCount() {

        return 0;
    }

    @Override
    public boolean hasStableIds() {

        return false;
    }
}

Answer 1

您的 getViewTypeCount 返回 0。根据 documentation :

If the adapter always returns the same type of View for all items, this method should return 1.

通过返回 0，您告诉系统您没有要显示的 View 类型。