如何添加子视图以使其与另一个视图重叠？

Question

I have the following subview

    webView = WKWebView(frame: CGRect(x: 3, y: horizontalLine.frame.maxY + 8, width: self.view.frame.width-6, height: CGFloat(self.view.frame.height - 150)))
    webView.navigationDelegate = self
    self.view.addSubview(webView)
    

I want to add the following subview on top of it (not inside it).

 textSizeChangeView = UIView(frame: CGRect(x: 0, y: textBtn.frame.maxY, width: self.view.frame.width, height: 100))
    textSizeChangeView.backgroundColor = UIColor(red: 0.97, green: 0.98, blue: 0.98, alpha: 1.00)
    
    let mySlider = UISlider(frame:CGRect(x: 10, y: 0, width: self.view.frame.width - 20, height: 30))
    self.textSizeChangeView.addSubview(mySlider)
    
    mySlider.center = self.textSizeChangeView.center
    
    mySlider.minimumValue = 1
    mySlider.maximumValue = 2
    mySlider.isContinuous = true
    mySlider.tintColor = UIColor(red: 0.33, green: 0.79, blue: 0.93, alpha: 1.00)
    textSizeChangeView.isHidden = true
    mySlider.addTarget(self, action: #selector(self.sliderValueChanged(sender:)), for: .valueChanged)

    self.view.addSubview(self.textSizeChangeView)

How can I do this?

Answer 1

The order of adding subviews matters.

If you want to make sure that textSizeChangeView will be on top of webView in case of overlapping then you need to make sure that self.view.addSubview(webView) is called before self.view.addSubview(self.textSizeChangeView) .