在widget提供者接收广播时替换RemoteViewsFactory。

Question

我有一个应用程序，其中有一个显示列表视图的小部件，我想根据用户在应用程序中打开的食谱更新列表。我想根据用户在应用程序中打开的食谱来更新列表。

要做到这一点，首先我发送了一个广播，当活动被打开时，有一个额外的整数。

然后在widget provider中，我用一个包含从广播中接收到的整数的意图来设置远程适配器。

现在我希望每次都能创建新的RemoteViewsFactory，这样我就可以从意图中提取一个整数，并根据这个数字加载不同的列表。

问题是这种情况只发生在应用程序第一次打开的时候，每隔一段时间只有MyWidgetRemoteViewsFactory中的onDataSetChanged()被调用，所以我无法获得配方号来正确更新数据。小组件中的列表从来没有得到更新。

如何强制widget重新创建RemoteViewsFactory？根据stackoverflow上的其他主题，我已经尝试在appWidgetManager.updateAppWidget(appWidgetId1, null)中传递null - 这没有工作。

MainListActivity.java - 发送广播

@Override
public void onItemClickListener(int itemID) {

    Intent recipeIntent = new Intent(this, BakingWidgetProvider.class);
    recipeIntent.setAction(BakingWidgetProvider.UPDATE_WIDGET_RECIPE);
    recipeIntent.putExtra(StepsListActivity.EXTRA_RECIPE_ID, itemID);
    sendBroadcast(recipeIntent);

    Intent intent = new Intent(MainListActivity.this, StepsListActivity.class);
    intent.putExtra(StepsListActivity.EXTRA_RECIPE_ID, itemID);
    startActivity(intent);

}

BakingWidgetProvider.java - 接收广播。

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

    AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);


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

        RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.baking_widget);

        int appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
        int viewIndex = intent.getIntExtra(StepsListActivity.EXTRA_RECIPE_ID, 0);

        int[] appWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, BakingWidgetProvider.class));

        for (int appWidgetId1 : appWidgetIds) {
             //trying to pass null to clear the data ?
            appWidgetManager.updateAppWidget(appWidgetId1, null);
        }

        Intent intent2 = new Intent(context, MyWidgetRemoteViewsService.class);
        Bundle bundle = new Bundle();
        bundle.putInt(StepsListActivity.EXTRA_RECIPE_ID,viewIndex );
        intent2.putExtras(bundle);

        remoteViews.setRemoteAdapter(R.id.list_view, intent2);

        appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds, R.id.list_view);

        //empty view
        remoteViews.setEmptyView(R.id.list_view, R.id.empty_view);

        for (int appWidgetId1 : appWidgetIds) {

           appWidgetManager.updateAppWidget(appWidgetId1, remoteViews);
        }

    }
    super.onReceive(context, intent);
}

MyWidgetRemoteViewsService.java - 从一个意图中获取一个整数来正确更新数据。

public class MyWidgetRemoteViewsService extends RemoteViewsService {

private static final String MyOnClick = "myOnClickTag";

@Override
public RemoteViewsFactory onGetViewFactory(Intent intent) {

    return new MyWidgetRemoteViewsFactory(this.getApplicationContext(), intent);
}

class MyWidgetRemoteViewsFactory implements RemoteViewsService.RemoteViewsFactory {

    List<Recipe> recipeList;
    private Context mContext;
    private int mRecipeOpen;

    public MyWidgetRemoteViewsFactory(Context context, Intent intent) {

        mRecipeOpen =  intent.getExtras().getInt(StepsListActivity.EXTRA_RECIPE_ID);
        mContext = context;

    }
    @Override
    public void onCreate() {
    }

    @Override
    public void onDataSetChanged() {
        recipeList = AppDatabase.getInstance(getApplicationContext()).recipeDao().getAll();
    }

    @Override
    public void onDestroy() {
    }

    @Override
    public int getCount() {
        return recipeList.get(mRecipeOpen).ingredients.size();
    }

    @Override
    public RemoteViews getViewAt(int position) {

        RemoteViews rv = new RemoteViews(mContext.getPackageName(), R.layout.widget_list_item);

        rv.setTextViewText(R.id.quantity, recipeList.get(mRecipeOpen).ingredients.get(position).getQuantity());
        rv.setTextViewText(R.id.measurement, recipeList.get(mRecipeOpen).ingredients.get(position).getMeasure());
        rv.setTextViewText(R.id.ingredient, recipeList.get(mRecipeOpen).ingredients.get(position).getIngredient());

        return rv;
    }

    @Override
    public RemoteViews getLoadingView() {
        return null;
    }

    @Override
    public int getViewTypeCount() {
        return 1;
    }

    @Override
    public long getItemId(int position) {
        return position;

    }

    @Override
    public boolean hasStableIds() {
        return true;

    }

}

}

Answer 1

最后，我不得不改变我的方法。

我把MyWidgetRemoteViewsFactory放在一个单独的类中，并扩展了BroadcastReceiver。在这里的onReceive方法中，我可以用所需的整数来检索从BakingWidgetProvider发送的广播。