Converting image url to bitmap quickly

Question

I need to display the list of images from api in the list page. For that i used two approaches.

First Approach:
By converting the url to byte array

Answer 1

There are open-source libraries which focus on loading image into an ImageView. Take for example of universal-image-loader, it is very easy to use, like:

// Load image, decode it to Bitmap and display Bitmap in ImageView (or any other view 
//  which implements ImageAware interface)
imageLoader.displayImage(imageUri, imageView);

or:

// Load image, decode it to Bitmap and return Bitmap to callback
imageLoader.loadImage(imageUri, new SimpleImageLoadingListener() {
    @Override
    public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
        // Do whatever you want with Bitmap
    }
});

or:

// Load image, decode it to Bitmap and return Bitmap synchronously
Bitmap bmp = imageLoader.loadImageSync(imageUri);

Take example of Volley, you can use it like this:

public void displayImg(View view){
    ImageView imageView = (ImageView)this.findViewById(R.id.image_view);
    RequestQueue mQueue = Volley.newRequestQueue(getApplicationContext()); 

    ImageLoader imageLoader = new ImageLoader(mQueue, new BitmapCache());

    ImageListener listener = ImageLoader.getImageListener(imageView,R.drawable.default_image, R.drawable.default_image);
    imageLoader.get("http://developer.android.com/images/home/aw_dac.png", listener);
    //指定图片允许的最大宽度和高度
    //imageLoader.get("http://developer.android.com/images/home/aw_dac.png",listener, 200, 200);
}

These libraries are used broadly, and more importantly, they are open-sourced. No need to implement functions like this repeatedly.