DUATranslationController
DUATranslationController并没有采用Scrollview的方式实现，而是基于controller容器，通过替换child controller来实现，具体来说就是当用户点击或者滑动时，判断需要展示上一个页面还是下一个页面，然后模仿UIpageviewcontroller通过回调的方式索取controller，加入到controller容器中，并通过动画的方式将新的controller平滑移动进入屏幕，旧的controller同时移出，如下是单击手势代码示例（滑动手势涉及和用户交互，逻辑更复杂些，但基本思路是一致的）
@objc func handleTapGes(gesture: UITapGestureRecognizer) -> Void {
let hitPoint = gesture.location(in: gesture.view)
let curController = self.childViewControllers.first!
if hitPoint.x < gesture.view!.frame.size.width/3 {
// 滑向上一个controller
let lastController = self.delegate?.translationController(translationController: self, controllerBefore: curController)
if lastController != nil {
self.delegate?.translationController(translationController: self, willTransitionTo: lastController!)
self.setViewController(viewController: lastController!, direction: .right, animated: allowAnimating, completionHandler: {(complete) in
self.delegate?.translationController(translationController: self, didFinishAnimating: complete, previousController: curController, transitionCompleted: complete)
})
}
}
if hitPoint.x > gesture.view!.frame.size.width*2/3 {
// 滑向下一个controller
let nextController: UIViewController? = self.delegate?.translationController(translationController: self, controllerAfter: self.childViewControllers.first!)
if nextController != nil {
self.delegate?.translationController(translationController: self, willTransitionTo: nextController!)
self.setViewController(viewController: nextController!, direction: .left, animated: allowAnimating, completionHandler: {(complete) in
self.delegate?.translationController(translationController: self, didFinishAnimating: complete, previousController: curController, transitionCompleted: complete)
})
}
}
}
// 该方法模仿UIpageviewcontroller，切换到某一个controller
func setViewController(viewController: UIViewController, direction: translationControllerNavigationDirection, animated: Bool, completionHandler: ((Bool) -> Void)?) -> Void {
if animated == false {
// 直接添加child controller ，略
}else {
let oldController = self.childViewControllers.first
self.addController(controller: viewController)
var newVCEndTransform: CGAffineTransform
var oldVCEndTransform: CGAffineTransform
viewController.view.transform = .identity
if direction == .left {
viewController.view.transform = CGAffineTransform(translationX: screenWidth, y: 0)
newVCEndTransform = .identity
oldController?.view.transform = .identity
oldVCEndTransform = CGAffineTransform(translationX: -screenWidth, y: 0)
}else {
viewController.view.transform = CGAffineTransform(translationX: -screenWidth, y: 0)
newVCEndTransform = .identity
oldController?.view.transform = .identity
oldVCEndTransform = CGAffineTransform(translationX: screenWidth, y: 0)
}
UIView.animate(withDuration: animationDuration, animations: {
oldController?.view.transform = oldVCEndTransform
viewController.view.transform = newVCEndTransform
}, completion: { (complete) in
if complete {
self.removeController(controller: oldController!)
}
if completionHandler != nil {
completionHandler!(complete)
}
})
}
}
