Notes from the May 16 talk, "A Moving Experience" at Google I/O 2013

A Moving Experience.md

A Moving Experience

Elements of Good Animations

• Keep them short, but appropriate to the action that is happening
  • (defaults to 300ms on Android for property animator)
• Keep them smooth
  • Don't run layout during animation! Do it first.
  • Use the right timing curve
• Keep them natural
  • Don't be whizzy for the sake of it, keep it organic to the app
• Keep them purposeful
  • No burning windows just for the sake of it
  • Make the animation exist for a reason

List Animation

• View.setHasTransientState(true), makes the list view leave those views alone while you animate them. If you don't - they might get recycled or whatever!
  • ViewPropertyAnimator sets this automatically for you

Activity Animations

• overridePendingTransition(0, 0); Tells the OS not to do any activity animation - we'll take care of it!
  • We also call it when we finish() so that we customize the exit animation

Cartoon Animation Techniques

• PropertyValuesHolder, ObjectAnimator - they're your friends!
• OvershootInterpolator gives you a nice wobble/bounce at the end of the animation
• AnimationSet for doing a series of animations in sequence
• Curved motion feels more natural than straight-line motion

Quick tips

• Avoid layout during the animation
• ViewTreeObserver can be used to listen to global events in the view hierarchy