如何在Swift中通过按钮按下迭代函数

Question

如何在Swift中通过按钮按下迭代函数

8

我正在学习Swift并构建一个AR应用程序，但似乎无法理解如何在每次单独的按钮按下时迭代通过几个函数。我已经创建了3个带有动画的函数，并希望按一次按钮来激活funcAnimation＃1，然后再次点击按钮以继续进行funcAnimation＃2等。

@IBAction func nextAnimation(_ sender: UIButton) {
funcAnimation#1()
funcAnimation#2()
funcAnimation#3()
}

当然，这里的问题是它们都同时激活。我想在每次按下按钮时只迭代一次。此外，我还想有一个返回按钮，可以将当前动画反转到上一个动画。我在苹果的文档中读到了有一个addTarget方法，但我不知道它是如何工作或如何实现它。请帮忙！

- Sam

使用一个计数器（整数）参数，在每次按钮点击时递增。添加一个条件，当达到限制时（即3），将该计数器设置为零。 - Bhavik Modi

1

你也可以使用完成处理程序。一旦函数运行结束，便会运行下一个函数。 - cyril

3个回答

1

另一种方法！

只需设置按钮1的标签（例如btnObj.tag=1）

并在按钮的操作中管理方法，例如

我的建议还是要管理flag以进行动画控制，例如如果第一个动画正在进行中，则第二个动画将等待完成后才能点击按钮，这样您的动画就不会出现错误。

var isAnimated = false;
@IBAction func myAnimationMethod(_ sender: UIButton) {
    if isAnimated {return} // Or display appropriate message by alert
    if (sender.tag == 1) {
        isAnimated=true
        funcAnimation1(...Your Code... After finish to set isAnimated=false)
        sender.tag = 2 
    }
    else if (sender.tag  == 2) {
       isAnimated=true
        funcAnimation2(...Your Code... After finish to set isAnimated=false)
        sender.tag = 3 
    }
    else if (sender.tag  == 3) {
         isAnimated=true
        funcAnimation3(...Your Code... After finish to set isAnimated=false)
        sender.tag = 1 
    }
}

- Govaadiyo

-1

您可以通过类似于此的返回按钮，将动画转发并返回到先前的动画状态。

步骤1：声明两个整数类型变量

var tapCount = 0 //For forwarding your animations from first to third
var currentAnimation = 0 // For reversing the animation from current animation

步骤2：在您的IBAction函数中

    @IBAction func nextAnimation(_ sender: Any)
    {
        if tapCount == 0
        {
            if currentAnimation == 1
            {
                Animation2()
            }
            else
            {
                Animation1()
            }
            tapCount += 1

        }
        else if tapCount == 1
        {
            if currentAnimation == 2
            {
                Animation3()
            }
            else
            {
                Animation2()
            }
            tapCount += 1
        }
        else if tapCount == 2
        {
            if currentAnimation == 3
            {
                Animation1()
            }
            else
            {
                Animation3()
            }
            tapCount = 0
        }
    }

步骤3：在您的函数中

    func Animation1()  {
        currentAnimation = 1
       print("First Animation")
    }
    func Animation2()  {
        currentAnimation = 2
         print("Second Animation")
    }
    func Animation3()  {
        currentAnimation = 3
     print("third Animation")
    }

步骤4：最后，用于从当前状态反转动画

@IBAction func backAnimation(_ sender: Any)
{
    if currentAnimation == 2
    {
         Animation1()

    }
    else if currentAnimation == 3
    {
        Animation2()

    }
    else
    {

    }
    tapCount = 0
}

希望能有所帮助！！

对于 addTarget(_:action:for:) 方法，可以在不连接 IBAction 并在需要时在 viewWillAppear 或 viewDidLoad 中声明的情况下完成。它将把目标对象和操作方法与控件关联起来。

例如：

    override func viewDidLoad() {
            super.viewDidLoad()
            // Do any additional setup after loading the view.
            nextButton.addTarget(self, action: #selector(self. nextAnimation), for: .touchUpInside) //Declared outlet as nextButton
            backButton.addTarget(self, action: #selector(self. backAnimation), for: .touchUpInside) //Declared outlet as backButton and this adds a target
        }
    @objc func nextAnimation(sender: UIButton) {
       // Do your stuff for next animation
    }
   @objc func backAnimation(sender: UIButton) {
       // Do your stuff for previous animation
    }

- Diksha235

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可以查看英文原文，
原文链接

- Jarvis The Avenger · Accepted Answer

你的代码应该像这样：

// You can define this variable globally...
var counter = 0
@IBAction func nextAnimation(_ sender: UIButton) {
    if (counter == 0) {
        funcAnimation1()
        // Increase counter count by 1 and you can add this line to completion of animation.
       // You can also disable your button interaction until your animation gets complete and that way you can handle your UI
        count += 1
    }
    else if (counter == 1) {
        funcAnimation2()
         // Increase counter count by 1 and you can add this line to completion of animation.
        count += 1
    }
    else if (counter == 2) {
        funcAnimation3()
        // set your counter to 0 again to loop through your animation.
        counter = 0
    }
}

你的“返回”操作应该像这样:

您的返回操作应该是这个样子:

@IBAction func backAnimation(_ sender: UIButton) {
    if (counter == 0) {
        funcAnimation1()
        // set your counter to 2 again to loop through your animation.
        count = 2
    }
    else if (counter == 1) {
        funcAnimation2()
        // decrease counter count by 1 and you can add this line to completion of animation.
        // You can also disable your button interaction until your animation gets complete and that way you can handle your UI
        count -= 1
    }
    else if (counter == 2) {
        funcAnimation3()
       // decrease counter count by 1 and you can add this line to completion of animation.
        count -= 1
    }
}