斯威夫特 - 何时或如何实现对视图动画的开始？ [英] Swift - when or how to implement animations on view start?

问题描述

我是新来的斯威夫特，我想实现一个简单的游戏。在这个游戏中，一旦视图被载入我想定期动画发生。

I'm new to Swift and I'm trying to implement a simple game. In this game, once the view is loaded I want periodic animations to happen.

问题是，我尝试动画我用的按钮，例如， button.frame.origin.x + = 50 ，但而不是从原点移动它以50像素的权利，它出现在button.frame.origin.x - 50进入其（初始位置）。
有趣的是，在一个点上我表现出 AlertDialog 给用户，并显示动画后开始如我所料的发生。

The problem is that I try to animate my buttons with, for instance, button.frame.origin.x += 50, but instead of moving it from the origin to 50px right, it appears at button.frame.origin.x - 50 and goes to its (initial) position. Funnily enough, at one point I show an AlertDialog to the user, and after it is shown the animation starts to happen as I expected.

我的问题是一样的这个话题，但接受的答案就是没有解决这个问题对我来说。

My problem is the same of this topic, but the accepted answer just didn't solve it for me.

有什么想法？

编辑：
挖掘到code和测试了很多，我发现，我显示AlertDialog也恰好我的无效计时器方法。我有两个定时器：一个更新UI时间（文本字段），另一个执行动画。两者都调度任务。从什么<一个href=\"https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSTimer_Class/index.html\"相对=nofollow>我读到这里，它是不可能有两个定时器这样。

Digging into the code and testing a lot I found out the method where I show the AlertDialog also happens to invalidate my timer. I have two timers: one to update the UI time (a TextField), and the other to perform the animation. Both are scheduling a task. From what I read here, it is not possible to have two timers like that.

一个计时器对象只能在一个运行循环，一次注册，
  虽然它可以被添加到多个运行循环模式，运行中
  循环。

A timer object can be registered in only one run loop at a time, although it can be added to multiple run loop modes within that run loop.

因此​​，显而易见的解决方案是将两个选择器（功能）合并成一个，这样的计时器将工作两个任务。但是，如果我尝试更新UI并执行动画，动画并不如预期不再工作。我只是失去了在这个问题上，不能使双方工作的事情。

Hence, the obvious solution would be to merge the two selectors (functions) into one, so the timer would work for both tasks. However, if I try to update the UI AND perform animations, the animations don't work as expected anymore. I'm just lost on this problem and can't make both things work.

这是我的code的重要棋子：

These are my important pieces of code:

override func viewDidAppear(animated: Bool) {
    super.viewDidAppear(animated)
    ...

    resetOrCreateGame()
}

func resetOrCreateGame() {
    // Do stuff to initialize values
    timerToRotate = NSTimer.scheduledTimerWithTimeInterval(2.0, target: self, selector: "rotateBlocks", userInfo: nil, repeats: true)
}

func rotateBlocks() {
    // Calculate positions to rotate
    UIView.animateWithDuration(0.5, delay: 0, options: UIViewAnimationOptions.CurveEaseOut, animations: {
        // Try to update a timer in the UI
        //self.timeLeft.text = String(self.seconds)

        for i in 0 ... 8 {
            println("\(i) before \(self.buttons[i].frame.origin.x) \(self.buttons[i].frame.origin.y)")
            self.buttons[i].frame.origin.x = self.positions[self.indicesToRotate[i]].x
            self.buttons[i].frame.origin.y = self.positions[self.indicesToRotate[i]].y

            println("\(i) after \(self.buttons[i].frame.origin.x) \(self.buttons[i].frame.origin.y)")
        }
        }, completion: { _ in
                println("completed")
            })

如果我离开行 self.timeLeft.text =字符串（self.seconds）评论说，动画做工精细。无论我怎样尝试更新的timeleft，如果我那样做，我的螺丝钉的动画。我试图更新它在一个单独的线程，其分派到主线程，甚至更新的动画闭包：这是行不通的。

If I leave the line self.timeLeft.text = String(self.seconds) commented, the animations work fine. No matter how I try to update the timeLeft, if I do so it screws my animations. I tried to update it in a separate thread, dispatch it to the main thread, or even update it inside the animations closure: it just doesn't work.

推荐答案

最后，我找到了解决办法！
由于某种原因，这个问题是自动布局。禁用后一切都如预期。

Finally, I found the solution! The problem for some reason was Auto Layout. After disabling it everything worked as expected.

希望它可以帮助别人的未来！

Hope it helps someone in the future!

这篇关于斯威夫特 - 何时或如何实现对视图动画的开始？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！