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如何消除animateKeyframes动画开始和结束时的延迟-Swift UIKit

uikit swift ios

fs_tigre · 技术社区 · 5 年前

有没有办法消除animateKeyframes动画开始和结束时的延迟?

正如你所看到的,动画开始前有一点延迟;在点击 Animate 按钮,也在动画的末尾。我想能做的是在动画开始后尽快开始 使有生气 点击按钮是为了向用户提供反馈。

这是使用时的正常行为吗 animateKeyframes 使用 calculationModeCubic ? 有没有办法让动画在点击按钮后立即启动?

抱歉拼写错误(Aniamate)。

以下是代码:

@IBAction func startAnimation(_ sender: Any) {
    addMyView()
    
    UIView.animateKeyframes(withDuration: 3.0, delay: 0.0, options: [.calculationModeCubic], animations: {
        UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.2, animations: {
            self.myView!.center =  CGPoint(x: self.pointA.center.x, y: self.pointA.center.y)
        })
        UIView.addKeyframe(withRelativeStartTime: 0.2, relativeDuration: 0.2, animations: {
            self.myView!.center =  CGPoint(x: self.pointB.center.x + 55, y: self.pointB.center.y - 5 )
            self.myView!.transform = CGAffineTransform(scaleX: 0.75, y: 0.75)
        })
        
        UIView.addKeyframe(withRelativeStartTime: 0.4, relativeDuration: 0.2, animations: {
            self.myView!.center =  CGPoint(x: self.pointB.center.x, y: self.pointB.center.y)
            self.myView!.transform = CGAffineTransform(scaleX: 0.5, y: 0.5)
        })
    }, completion: { _ in
        self.myView?.removeFromSuperview()
    })
}

func addMyView(){
    myView = UIView(frame: CGRect(x: pointA.center.x - 25, y: pointA.center.y - 25, width: 50, height: 50))
    myView?.backgroundColor = .blue
    myView?.layer.cornerRadius = myView!.frame.height / 2
    view.addSubview(myView!)
}

0 回复 | 直到 5 年前

fs_tigre 5 年前

关键是要不断调整 withRelativeStartTime: 还有 relativeDuration: 参数。

@IBAction func startAnimation(_ sender: Any) {
    addMyView()
      UIView.animateKeyframes(withDuration: 1.5, delay: 0.0, options: [.calculationModeCubic], animations: {
        UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.2, animations: {
            self.myView!.center =  CGPoint(x: self.pointA.center.x, y: self.pointA.center.y)
        })
        UIView.addKeyframe(withRelativeStartTime: 0.0, relativeDuration: 0.9, animations: {
            self.myView!.center =  CGPoint(x: self.pointB.center.x + 75, y: self.pointB.center.y - 50 )
            self.myView!.transform = CGAffineTransform(scaleX: 0.75, y: 0.75)
        })
        
        UIView.addKeyframe(withRelativeStartTime: 0.1, relativeDuration: 0.7, animations: {
            self.myView!.center =  CGPoint(x: self.pointB.center.x, y: self.pointB.center.y)
            self.myView!.transform = CGAffineTransform(scaleX: 0.3, y: 0.3)
        })
    }, completion: { _ in
        self.myView?.removeFromSuperview()
    })      

}