[转]IFTTT开源Swift编写的帧动画框架--RazzleDazzle

RazzleDazzle 是IFTTT开源的一个iOS帧动画框架，用Swift编写，非常适用于APP初次使用时的介绍和引导信息。RazzleDazzle由IFTTT此前开源的一款Objective-C滚动帧动画库JazzHands发展而来。JazzHands是UIKit一个简单的关键帧基础动画框架，可通过手势、scrollview、KVO或者ReactiveCocoa控制动画，被IFTTT应用在IFTTT for iPhone上。多款知名应用程序都使用了JazzHands这个框架，目前其在github上有3688个star。对于RazzleDazzle，开发者除了使用RazzleDazzle支持的动画类型外，还可以使用自定义动画类型。

RazzleDazzle支持的动画类型：

• AlphaAnimation animates the alpha property (creates fade effects).
• BackgroundColorAnimation animates the backgroundColor property.
• RotationAnimation animates a rotation transform (for rotation effects).
• ScaleAnimation applies a scaling transform (to scale view sizes).
• TranslationAnimation applies a translation transform (to translate view position).
• CornerRadiusAnimation animates the layer.cornerRadius property.
• HideAnimation animates the hidden property (hides and shows views).
• LayerStrokeStartAnimation animates the strokeStart property of a CAShapeLayer (does not work with LayerStrokeEndAnimation).
• LayerStrokeEndAnimation animates the strokeEnd property of a CAShapeLayer (does not work with LayerStrokeStartAnimation).
• LayerFillColorAnimation animates the fillColor property of a CAShapeLayer.
• LayerStrokeColorAnimation animates the strokeColor property of a CAShapeLayer.
• PathPositionAnimation animates the layer.position property of a UIView along a path.
• LabelTextColorAnimation animates the textColor property of a UILabel.
• ConstraintConstantAnimation animates an AutoLayout constraint constant.
• ConstraintMultiplierAnimation animates an AutoLayout constraint constant as a multiple of an attribute of another view (to offset or resize views based on another view‘s size)
• ScrollViewPageConstraintAnimation animates an AutoLayout constraint constant to place a view on a scroll view page (to position views on a scrollView using AutoLayout). This is the animation doing the heavy lifting for AnimatedPagingScrollViewController‘s keepView(view: onPage:) function.