The document provides an overview of the Animator framework used in animation within app development, detailing concepts, functions, and capabilities of the Animator class. It explains how animators can calculate and modify values over time using both linear and non-linear equations, along with common features such as repeat modes and the use of listeners. Additionally, there are live coding demos and scheduled workshops for further learning on related topics.

1. Animator
Charlie@Android Study Group

2. Charlie Tsai@Android Study Group
cha122977@gmail.com
Individual App Developer &
System Software Engineer@NVIDIA
Today’s source code
https://github.com/chatea/AnimatorDemo

3. Agenda
• Animation vs Animator
• Concepts and usages of animator
• Class overview
• Features of Animator
• Demo and Live Coding

4. Animation vs Animator
• Animation:
For View only
xml supported
Modify(animate) the fixed attributes of View
• Animator:
For everything
xml supported
Modify(animate) any value you gave

5. Animator Go!

6. What does Animator do?
• Give you a calculated value depends on the time
• It uses Equation (數學方程式) to calculate the value

7. Linear Case
TimeStart
Duration:10sstart value = 0
end value =100
get value at t = 2s
Value = (100 - 0) * (2/10) = 20
get value at t = 8s
Value = (100 - 0) * (8/10) = 80
f(s) = A * s

8. Abilities of Animator
• Support customized calculation function
• Support modifying class member
(By ObjectAnimator)

9. Non-Linear Case
TimeStart
Duration:10sstart value = 0
end value =100
get value at t = 2s
Value = (100 - 0) * (2/10)^2 = 4
get value at t = 8s
Value = (100 - 0) * (8/10)^2 = 64
f(s) = A * s^2

10. Setup Animator
• Create a Animator
• Set start and end values
• Set duration
• Start!

11. Use Animator
• Get the new animated value from animator
• Apply the new value to your components.
(e.g. invalid your View object)
Demo 1

12. Class Overview
Animator
AnimatorSet ValueAnimator
ObjectAnimator TimeAnimator

13. Common Features
• Repeat mode (e.g. restart, reverse)
Repeat count (e.g. 1, 6, infinity)
• AnimatorSet: combine multiple animators
• Add listener(s)
onAnimatorStart/End/Cancel/Repeat/…etc.
• Set interpolator (時間與數值的對應函數)
Linear, Accelerate, Decelerate, Path, etc
Demo 2, 3
Demo 4
Demo 5

14. Advanced features
• Multiple Values in same Animator
• ObjectAnimator
• TimeAnimator
• defined by XML
• TypeEvaluator
• PathIntepolator
Demo 6
Demo 8
Demo 7

15. Live Coding
Demo 9, 10, Live

16. 固定聚會：每週三＠菓子咖啡(近捷運南京復興站)
7/30(六)下午將舉辦Workshop：
利用Firebase打造個人專屬聊天app
歡迎想學習Firebase者及其他領域開發者

17. Question?

18. Thanks!