The Developers site released a training guide for UI related stuff, this is the index:
For Your Custom view , i suggest you identify the Properties that you want to Animate on .
Let's say a ClockView, You After setting paint,stroke and so on in OnDraw()
You might wanna have AsyncMethods/Runnables which updates the Properties continuously in background , resulting in Frame by frame animation , but it isn't Fraame Animation actually , because you are animating only the properties of view (turn left) and not he tentire frame
There are dozens of examples out there, With little googling you can DIY