title: how to enable floating notification and lock screen notification in xamarin android(Java or Kotlin is okay)
body: <p>I make simple notification android app using xamarin,
  i want floating notification and lock screen notification
  <a href="https://i.stack.imgur.com/aZIRf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/aZIRf.png" alt="enter image description here" /></a></p>
  <p>l add users permission in manifest, also i read all reference document about notification channel however i don't know how to enable floating notification and lock screen notification in code</p>
  <p>outlook, gmail etc. some app enable all notification when it installed</p>
  <p><a href="https://i.stack.imgur.com/AIRtj.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AIRtj.jpg" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/iRG9s.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/iRG9s.jpg" alt="enter image description here" /></a></p>
  <p><a href="https://i.stack.imgur.com/rDLqf.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/rDLqf.jpg" alt="enter image description here" /></a></p>
  <p>above screenshot is my app</p>
  <p>i want enable all notification when installed my app
  necessarily Even if it is not in xamarin, a solution using kotlin or java is fine!</p>