android - Download image from URL, show it as a circular image with default behaviour -

after stucking few days on problem wanted share solution , save time.

problem
1. download image url
2. show circular image (if download succeeded)
3. or show default image in same imageview (if download failed)

[edit] removed answer because of useful hints coming @budius , better working solution offers below

best way achieve task question using picasso circular transformation.

like following code:

picasso   .with(context)   .load(url)   .placeholder(placeholderdrawable)   .error(errordrawable)   .transform(circletransform)   .into(imageview); 

and code circletransform copied link: https://gist.github.com/julianshen/5829333

public class circletransform implements transformation {     @override     public bitmap transform(bitmap source) {         int size = math.min(source.getwidth(), source.getheight());          int x = (source.getwidth() - size) / 2;         int y = (source.getheight() - size) / 2;          bitmap squaredbitmap = bitmap.createbitmap(source, x, y, size, size);         if (squaredbitmap != source) {             source.recycle();         }          bitmap bitmap = bitmap.createbitmap(size, size, source.getconfig());          canvas canvas = new canvas(bitmap);         paint paint = new paint();         bitmapshader shader = new bitmapshader(squaredbitmap, bitmapshader.tilemode.clamp, bitmapshader.tilemode.clamp);         paint.setshader(shader);         paint.setantialias(true);          float r = size/2f;         canvas.drawcircle(r, r, r, paint);          squaredbitmap.recycle();         return bitmap;     }      @override     public string key() {         return "circle";     } }