Question

这是一个简单的小部件，它显示了从外部存储器获取的一组位图。它基本上可以工作，但是让monit认为App在其主线程上做了太多工作，所以我把东西放在AsyncTask中，但是widget仍然是空的，没有加载位图。这是有效的代码：

public class PhotosLoader /*extends AsyncTask<Void, Void ,ArrayList<Bitmap>> */ {
    private Context mContext;
    private RemoteViews views;
    private ArrayList<Bitmap> images;

    public PhotosLoader (Context context, RemoteViews views){
        mContext = context;
        this.views = views;
    }

    public ArrayList<Bitmap> LoadPhotos() {
        PhotosReader PR = new PhotosReader();
        images = PR.getPhotosArray(mContext);
        PhotosModifier PM = new PhotosModifier();
        ArrayList<Bitmap> bitmaps = PM.getResizedPhotosBitmap(images);
        return bitmaps;
    }

    public void inflatePhotos(ArrayList<Bitmap> bitmaps){
        views.setImageViewBitmap(R.id.imageView, bitmaps.get(0));
        views.setImageViewBitmap(R.id.imageView2, bitmaps.get(1));
        views.setImageViewBitmap(R.id.imageView3, bitmaps.get(2));
        views.setImageViewBitmap(R.id.imageView4, bitmaps.get(3));
        views.setImageViewBitmap(R.id.imageView5, bitmaps.get(4));
    }
}

onUpdate方法：

 public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        // There may be multiple widgets active, so update all of them
        for (int appWidgetId : appWidgetIds) {
            updateAppWidget(context, appWidgetManager, appWidgetId);

            RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.new_app_widget);
            PhotosLoader PL = new PhotosLoader(context, views);
            ArrayList<Bitmap> bitmaps = PL.LoadPhotos();
            PL.inflatePhotos(bitmaps);
        }
    }

并且有代码没有：

public class PhotosLoader extends AsyncTask<Void, Void ,ArrayList<Bitmap>> {
    private Context mContext;
    private RemoteViews views;
    private ArrayList<Bitmap> images;

    public PhotosLoader (Context context, RemoteViews views){
        mContext = context;
        this.views = views;
    }

    @Override
    protected ArrayList<Bitmap> doInBackground(Void... voids) {
        PhotosReader PR = new PhotosReader();
        images = PR.getPhotosArray(mContext);
        PhotosModifier PM = new PhotosModifier();
        ArrayList<Bitmap> bitmaps = PM.getResizedPhotosBitmap(images);
        return bitmaps;
    }

    @Override
    protected void onPostExecute(ArrayList<Bitmap> bitmaps) {
        super.onPostExecute(bitmaps);
        views.setImageViewBitmap(R.id.imageView, bitmaps.get(0));
        views.setImageViewBitmap(R.id.imageView2, bitmaps.get(1));
        views.setImageViewBitmap(R.id.imageView3, bitmaps.get(2));
        views.setImageViewBitmap(R.id.imageView4, bitmaps.get(3));
        views.setImageViewBitmap(R.id.imageView5, bitmaps.get(4));
    }
}

onUpdate：

   @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        // There may be multiple widgets active, so update all of them
        for (int appWidgetId : appWidgetIds) {
            updateAppWidget(context, appWidgetManager, appWidgetId);

            RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.new_app_widget);
            new PhotosLoader(context, views).execute();
            Log.d("Main","onUpdate");
        }
    }

那些只是项目中的代码更改，我第一次执行AsyncTask，所以Idk我做错了什么，看起来很简单

Answer 1

我认为问题在于您在之后尝试更新RemoteView对象，并从onUpdate方法返回它。您应该将已经构建的内容返回并填入所需的数据。

也许尝试采用与传递位图不同的方法，并将Uri设置为ImageView上的图片？

编辑：实际上，还有一个问题可能是您实际上没有在任何地方更新窗口小部件：D您创建RemoteView然后删除它。你打电话给appWidgetManager.updateAppWidget吗？

应用程序在实现AsyncTask后不显示任何内容

1 个答案: