縮放Fresco圖片

 int width = 50, height = 50;
        ImageRequest request = ImageRequestBuilder.newBuilderWithSource(Uri.parse("http://www.taopic.com/uploads/allimg/110730/1716-110I011363240.jpg"))
                .setResizeOptions(new ResizeOptions(width, height))
                .build();
        AbstractDraweeController controller = Fresco.newDraweeControllerBuilder()
                .setOldController(simpleDraweeView.getController())
                .setImageRequest(request)
                .build();
        simpleDraweeView.setController(controller);