URL imageurl = new URL("http://mysite.com/me.jpg");
Bitmap bitmap = BitmapFactory.decodeStream(imageurl.openConnection().getInputStream());
This code will help you in generating the bitmap from the image url.
This question answers the second part.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…