Question

我正在尝试在TabBar中的选项卡之间实现交互式动画过渡。我正在使用平移手势识别器。我制作了一个自定义动画，并使用UIPercentDrivenInteractiveTransition使切换交互。但似乎我并不真正理解所有动画背后的过程我确实设法制作了一个非交互式动画，但添加交互性在某种程度上是困难的。我在互联网上阅读了很多教程，并且我完全理解每个人发布的代码片段是如何工作的，但我在某种程度上无法实现它。我制作了一个TabBar应用程序，其中包含两个带导航栏的选项卡这是我的代码：

TabBarController.swift

import UIKit

class TabBarController: UITabBarController, UITabBarControllerDelegate {

var usingGesture = false
var interactiveTransition:UIPercentDrivenInteractiveTransition?

override func viewDidLoad() {
    super.viewDidLoad()
    let panGesture = UIPanGestureRecognizer(target: self, action: "didPan:")
    self.view.addGestureRecognizer(panGesture)
    self.delegate = self
    // Do any additional setup after loading the view.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func tabBarController(tabBarController: UITabBarController, interactionControllerForAnimationController animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
    return self.interactiveTransition
}

func didPan(gesture: UIPanGestureRecognizer){
    let point = gesture.locationInView(gesture.view)
    let percent = fmax(fmin((point.x / 300.0), 0.99), 0.0)
    self.interactiveTransition = UIPercentDrivenInteractiveTransition()

    switch (gesture.state){
    case .Began:
        self.usingGesture = true
        self.selectedIndex++
    case .Changed:
        self.interactiveTransition?.updateInteractiveTransition(percent)
    case .Ended, .Cancelled:
        if percent > 0.5 {
            self.interactiveTransition?.finishInteractiveTransition()
        } else {
            self.interactiveTransition?.cancelInteractiveTransition()
        }
        self.usingGesture = false
    default:
        NSLog("Unhandled state")
    }
}
}

TransitionToLeft.swift

import UIKit

class TransitionToLeft: UIPercentDrivenInteractiveTransition, UIViewControllerAnimatedTransitioning {

func animateTransition(transitionContext: UIViewControllerContextTransitioning) {

    let fromView:UIView = transitionContext.viewForKey(UITransitionContextFromViewKey)!
    let toView:UIView = transitionContext.viewForKey(UITransitionContextToViewKey)!

    transitionContext.containerView().addSubview(fromView)
    transitionContext.containerView().addSubview(toView)

    toView.frame = CGRectMake(toView.frame.width, 0, toView.frame.width, toView.frame.height)
    let fromNewFrame = CGRectMake(-1 * fromView.frame.width, 0, fromView.frame.width, fromView.frame.height)

    UIView.animateWithDuration( 0.7, animations:{ () -> Void in
        toView.frame = fromView.frame
        fromView.frame = fromNewFrame
        },{ (Bool) -> Void in
            // update internal view - must always be called
            transitionContext.completeTransition(true)
    })

}
func transitionDuration(transitionContext: UIViewControllerContextTransitioning) -> NSTimeInterval {
    return 0.7
}

}

有人可以帮我解决这个问题吗？

Answer 1

我认为您的问题出在手势识别器中。尝试将其添加到self.selectedViewController.view而不是self.view。

此外，您的代码有误：我认为self.interactiveTransition = UIPercentDrivenInteractiveTransition()应为self.interactiveTransition = TransitionToLeft()。

具有交互式动画过渡的TabBarController

1 个答案: