为什么使用fresco数据源获取位图是空的

Question

为什么位图返回onNewResultImplnull？

final ImageView imageView = (ImageView) findViewById (R.id.imageView);

ImageRequest request = ImageRequest.fromUri(pic_uri);

ImagePipeline imagePipeline = Fresco.getImagePipeline();
DataSource dataSource = imagePipeline.fetchEncodedImage(request, this);
CloseableReference<CloseableImage> imageReference = null;
dataSource.subscribe (new BaseBitmapDataSubscriber() {
    @Override
    protected void onNewResultImpl(Bitmap bitmap) {
        LogUtils._d("onNewResultImpl....");
        if(bitmap == null) {
            LogUtils._d("bitmap is null");
        }
        imageView.setImageBitmap(bitmap);
    }

    @Override
    protected void onFailureImpl(DataSource dataSource) {
        LogUtils._d("onFailureImpl....");
    }
}, CallerThreadExecutor.getInstance());

Answer 1

我做了一些修改,以使代码工作正常,考虑使用它.我也测试了它,它工作得很好.

// To get image using Fresco
ImageRequest imageRequest = ImageRequestBuilder
          .newBuilderWithSource( Uri.parse(getFeedItem(position).feedImageUrl.get(index)))
          .setProgressiveRenderingEnabled(true)
          .build();

ImagePipeline imagePipeline = Fresco.getImagePipeline();
DataSource<CloseableReference<CloseableImage>> dataSource = 
                              imagePipeline.fetchDecodedImage(imageRequest,mContext);

 dataSource.subscribe(new BaseBitmapDataSubscriber() {

     @Override
     public void onNewResultImpl(@Nullable Bitmap bitmap) {
         // You can use the bitmap in only limited ways
         // No need to do any cleanup.
     }

     @Override
     public void onFailureImpl(DataSource dataSource) {
         // No cleanup required here.
     }

 }, CallerThreadExecutor.getInstance());