Circular reveal animation on dialog in android

Defining Custom Animations

Animations in material design give users feedback on their actions and provide visual continuity as users interact with your app. The material theme provides some default animations for buttons and activity transitions, and Android 5.0 (API level 21) and above lets you customize these animations and create new ones:

Using android.support.design in android

Android Design Support Library

With a little help from the new Android Design Support Library, Google bringing a number of important material design components to all developers and to all Android 2.1 or higher devices. You’ll find a navigation drawer view, floating labels for editing text, a floating action button, snackbar, tabs, and a motion and scroll framework to tie them together.

Transitions in android

Shared Element Activity Transition

Traditionally transitions between different activities or fragments involved enter and exit transitions that animated entire view hierarchies independent to each other. Example of such transitions are a fade transition, slide transition or the newly introduced explode transition.
     Many times, there are elements common to both activities and providing the ability to transition these shared elements separately emphasizes continuity between transitions and breaks activity boundaries as the user navigates the app.