Loading countdown for retrieving images from the firebase

how to add Loading countdown (100 to 0) during retrieving images from the firebase. when images are loaded then their visibility occur. before the loading countdown should be visible. when it reach the limit of 0 in the meantime the images should be load behind it from the firebase.

You want to use Asynchronous loading.

This is the best one to use in my opinion. Built by @Abhijith_Dominic