title: How to make circular reveal effect when theme changed? (Like in Telegram or VK)
body: <p>I am using <a href="https://medium.com/androiddevelopers/appcompat-v23-2-daynight-d10f90c83e94" rel="noreferrer">DayNight</a> theme in my application. And I have a button that changes the theme. In VK and Telegram app there is a beautiful reveal animation that changes the theme without restarting activity or something like that. </p>
  
  <p>I have tried to make that with <a href="https://medium.com/@daniele.orlando/beautiful-circular-reveal-animation-on-android-1b5aaca2dd1f" rel="noreferrer">reveal animation implementation</a> in different ways, but it doesn't work or working bad in some cases with AppCompatDelegate.setDefaultNightMode(...). All examples with that reveal animation are for ActivityA -> ActivityB, but I just need to update theme without starting any activity.</p>
  
  <p>And one more thing: AppCompatDelegate.setDefaultNightMode recreates my activity, so do I need a custom theme changing implementation?</p>
  
  <p>And main question: how to create that animation with theme changing?</p>
  
  <p>Examples:</p>
  
  <p><a href="https://i.stack.imgur.com/2gQix.jpg" rel="noreferrer">Telegram (From Dark to Light)</a></p>
  
  <p><a href="https://i.stack.imgur.com/QVl4a.jpg" rel="noreferrer">Telegram (From Light to Dark)</a></p>
  
  <p><a href="https://i.stack.imgur.com/Nef2G.jpg" rel="noreferrer">VK (From Light to Dark)</a></p>
  
  <p><a href="https://i.stack.imgur.com/EIXON.jpg" rel="noreferrer">VK (From Dark to Light)</a></p>