UISlider无法更新值

Question

很抱歉，如果这是一个愚蠢的问题。我似乎无法让我的滑块在与之交互时更新其值。 （我将把每个人都指向这段长代码中的最后一个方法）

class CustomSlider: UISlider {

    override func trackRect(forBounds bounds: CGRect) -> CGRect {
        var rect = super.trackRect(forBounds: bounds)
        rect.size.height = 7
        return rect
    }
}

class FactionButton: CustomSlider {
    var factionSlider = CustomSlider(frame: CGRect(x: 15, y: 542, width: 386, height: 57))

    func factionBalanceSlider(){
        factionSlider.minimumValueImage = #imageLiteral(resourceName: "Alliance Slider")
        factionSlider.maximumValueImage = #imageLiteral(resourceName: "Horde Slider")
        factionSlider.setThumbImage(#imageLiteral(resourceName: "Thumb Image"), for: .normal)
        factionSlider.minimumTrackTintColor = UIColor(red:0.08, green:0.33, blue:0.69, alpha:0.8)
        factionSlider.maximumTrackTintColor = UIColor(red:1.00, green:0.00, blue:0.00, alpha:0.59)

        factionSlider.setValue(0.5, animated: true)
        factionSlider.isContinuous = false

        factionSlider.addTarget(self, action: #selector(recordFactionBalance(sender:)), for: .valueChanged)
    }

    func getSlider() -> CustomSlider {
        return factionSlider
    }

    override func trackRect(forBounds bounds: CGRect) -> CGRect {
        var customBounds = super.trackRect(forBounds: bounds)
        customBounds.size.height = 10
        return customBounds
    }

    @objc func recordFactionBalance(sender: CustomSlider){
        //also calculates balance and adds it into the quiz data
        print("hi")
        print(sender.value) //It's this part that doesn't work 

    }

}

这是最接近问题底部的位置。 （其他都很好）动作功能似乎根本没有被触发，即使我正在与之交互。这两个打印语句均未执行。有什么想法吗？

欢呼

Answer 1

我可以从getSlider()中猜测您正在使用此class作为实用程序来获取CustomSlider。因此，我怀疑您是按照以下方式将滑块添加到view，

let container = FactionButton()
container.factionBalanceSlider()
let slider = container.getSlider()

self.view.addSubview(slider)

如果您不将container添加到view中，而.valueChange被设置为container事件的接收者，那么它将不会得到任何事件。要接收事件，您还需要在view中添加self.view.addSubview(container) ，如下所示，

<script
  src="https://code.jquery.com/jquery-3.3.1.min.js"
  integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8="
  crossorigin="anonymous"></script>

<script>
    $(document).ready(function(){

    var classCounter = $('.style_prevu_kit').length; // count of all style_prevu_kit classes
    var activeIndex = 0; //set active index to first style_prevu_kit class

     $('body').keydown(function(e) {
       var code = e.keyCode || e.which; 
       if (code == 9) { // 9 is code for the [tab] key
       e.preventDefault(); // prevents [tab] key default behaviour
          $('.style_prevu_kit').eq(activeIndex-1).removeClass('active');
          $('.style_prevu_kit').eq(activeIndex++).addClass('active');  
          if(activeIndex>classCounter-1){
             activeIndex = 0;
          } // reset active index when it exceeds number of class elements
       }
    });

    $(".style_prevu_kit").on("mouseover", function() {
    console.log($('.style_prevu_kit').index($(this)));
        $('.style_prevu_kit').each(function(){
            $(this).removeClass('active');
        })
        activeIndex = 0; 
    }); //reset Index when manual mouse hover activated

    }) //end document ready

</script>

<link href='https://fonts.googleapis.com/css?family=Roboto:100,400,300,500,700' rel='stylesheet' type='text/css'>

<style>
.fond{position:absolute;padding-top:85px;top:0;left:0; right:0;bottom:0;
 background-color:#00506b;}

.style_prevu_kit
{
    display:inline-block;
    border:0;
    width:196px;
    height:210px;
    position: relative;
    -webkit-transition: all 200ms ease-in;
    -webkit-transform: scale(1); 
    -ms-transition: all 200ms ease-in;
    -ms-transform: scale(1); 
    -moz-transition: all 200ms ease-in;
    -moz-transform: scale(1);
    transition: all 200ms ease-in;
    transform: scale(1);   
     overflow: hidden;

}
.style_prevu_kit:hover
{
    box-shadow: 0px 0px 150px #000000;
    z-index: 2;
    -webkit-transition: all 200ms ease-in;
    -webkit-transform: scale(1.5);
    -ms-transition: all 200ms ease-in;
    -ms-transform: scale(1.5);   
    -moz-transition: all 200ms ease-in;
    -moz-transform: scale(1.5);
    transition: all 200ms ease-in;
    transform: scale(1.5);
    border:2px solid green;
    height: 300px;
}

.active{
    box-shadow: 0px 0px 150px #000000;
    z-index: 2;
    -webkit-transition: all 200ms ease-in;
    -webkit-transform: scale(1.5);
    -ms-transition: all 200ms ease-in;
    -ms-transform: scale(1.5);   
    -moz-transition: all 200ms ease-in;
    -moz-transform: scale(1.5);
    transition: all 200ms ease-in;
    transform: scale(1.5);
    border:2px solid green;
    height: 300px;
}

</style>

<div align="center" class="fond">
<div style="width:1000px;">

<div class="style_prevu_kit active" style="background-color:#cb2025;">
   <ul>
      <li>hello world1</li>
      <li>hello world2</li>
      <li>hello world3</li>
      <li>hello world4</li>
      <li>hello world5</li>
      <li>hello world6</li>
      <li>hello world7</li>
      <li>hello world8</li>
      <li>hello world9</li>
      <li>hello world10</li>
     <li>hello world11</li>
     <li>hello world12</li>
     <li>hello world13</li>
     <li>hello world14</li>
     <li>hello world15</li>
    </ul>
  </div>
<div class="style_prevu_kit" style="background-color:#f8b334;">
   <ul>
      <li>hello world1</li>
      <li>hello world2</li>
      <li>hello world3</li>
      <li>hello world4</li>
      <li>hello world5</li>
      <li>hello world6</li>
      <li>hello world7</li>
      <li>hello world8</li>
      <li>hello world9</li>
      <li>hello world10</li>
     <li>hello world11</li>
     <li>hello world12</li>
     <li>hello world13</li>
     <li>hello world14</li>
     <li>hello world15</li>
    </ul>
  </div>
<div class="style_prevu_kit" style="background-color:#97bf0d;">
   <ul>
      <li>hello world1</li>
      <li>hello world2</li>
      <li>hello world3</li>
      <li>hello world4</li>
      <li>hello world5</li>
      <li>hello world6</li>
      <li>hello world7</li>
      <li>hello world8</li>
      <li>hello world9</li>
      <li>hello world10</li>
     <li>hello world11</li>
     <li>hello world12</li>
     <li>hello world13</li>
     <li>hello world14</li>
     <li>hello world15</li>
    </ul>
  </div>
<div class="style_prevu_kit" style="background-color:#00a096;">
   <ul>
      <li>hello world1</li>
      <li>hello world2</li>
      <li>hello world3</li>
      <li>hello world4</li>
      <li>hello world5</li>
      <li>hello world6</li>
      <li>hello world7</li>
      <li>hello world8</li>
      <li>hello world9</li>
      <li>hello world10</li>
     <li>hello world11</li>
     <li>hello world12</li>
     <li>hello world13</li>
     <li>hello world14</li>
     <li>hello world15</li>
    </ul>
  </div>
<div class="style_prevu_kit" style="background-color:#93a6a8;">
    <ul>
      <li>hello world1</li>
      <li>hello world2</li>
      <li>hello world3</li>
      <li>hello world4</li>
      <li>hello world5</li>
      <li>hello world6</li>
      <li>hello world7</li>
      <li>hello world8</li>
      <li>hello world9</li>
      <li>hello world10</li>
     <li>hello world11</li>
     <li>hello world12</li>
     <li>hello world13</li>
     <li>hello world14</li>
     <li>hello world15</li>
    </ul>
  </div>

</div>
</div>