解決這個問提一種方法就是讓UI直接切圓角圖;另一箇中就是通過thumbnail方法對佔位圖再做圓角處理,具體實現如下：

    public static void loadRoundImg(ImageView imageView, String url, @DrawableRes int placeholderId,
                                    @DrawableRes int errorId, float radius) {

        Glide.with(imageView.getContext()).load(url)
                .
 
apply(new RequestOptions().placeholder(placeholderId).error(errorId).centerCrop()
                        .transform(new GlideRoundTransform(imageView.getContext(), radius)))
                .thumbnail(loadTransform(imageView.getContext(),placeholderId,radius))
                .thumbnail(loadTransform
 
(imageView.getContext(),errorId,radius))
                .into(imageView);
    }
    
     private static  RequestBuilder<Drawable> loadTransform(Context context, @DrawableRes int placeholderId, float radius) {

        return Glide.with(context)
                .load(placeholderId)
                .
 
apply(new RequestOptions().centerCrop()
                        .transform(new GlideRoundTransform(context, radius)));

    }