Android icon not changing

I found that I had to delete ic_launcher.xml since this contains a path with the default icon encoded in it.

The problem was with MIUI caching application icons. I searched and removed the existing icon and everything worked as expected from now then.

MIUI icon caching problem still present as of MIUI 9

Step to clear caching: Settings > Installed Apps > Search for your app > Storage > Clear cache > Restart your phone

Change your theme if you are using MIUI. Icon will refresh..