public interface TypeEvaluator<T>
ValueAnimator.setEvaluator(TypeEvaluator) function. Evaluators
allow developers to create animations on arbitrary property types, by allowing them to supply
custom evaulators for types that are not automatically understood and used by the animation
system.T evaluate(float fraction, T startValue, T endValue)
fraction representing the proportion between the start and end values. The
calculation is a simple parametric calculation: result = x0 + t * (v1 - v0),
where x0 is startValue, x1 is endValue,
and t is fraction.fraction - The fraction from the starting to the ending valuesstartValue - The start value.endValue - The end value.fraction parameter.