无法设置滚动的宽度查看iOS Swift

Question

I am unable to set the width of the scrollView to the width of the screen. Could someone please guide where I am going wrong ?

Here is how I have enabled a scroll view

// SCROLL VIEW
var scrollView = UIScrollView()
var contentView = UIView()


override func viewDidLoad() {
    super.viewDidLoad()

    screenHeight    = screenSize.height
    screenWidth     = screenSize.width

    // SCROLL VIEW
    scrollView = UIScrollView(frame: view.bounds)

   // Here I am adding all my labels and textview fields to content view
   contentView.addSubview(problemDescriptionStackView)
   ....

    // Adding content view to the scrollView
    scrollView.addSubview(contentView)

    // Pinning the contentView to the scroll view
    pinView(contentView, to: scrollView)

    self.view.addSubview(scrollView)

    // Here I am Setting the constraints for all the items in the contentView
    ....
}

// The below functions are used to pin one view to another view

   public func pinView(_ view: UIView, to scrollView: UIScrollView) {
        view.translatesAutoresizingMaskIntoConstraints = false
        view.pin(to: scrollView)
    }

    public func pin(to view: UIView) {
        NSLayoutConstraint.activate([
            leadingAnchor.constraint(equalTo: view.leadingAnchor),
            trailingAnchor.constraint(equalTo: view.trailingAnchor),
            topAnchor.constraint(equalTo: view.topAnchor),
            bottomAnchor.constraint(equalTo: view.bottomAnchor)
            ])
    }

Answer 1

Use below methods for get exact size of screen accordingly iPhone. Hope using this method, your problem solved. If you have doubt Please comment here.

//MARK: - Main Screen Width

func getScreenWidth() -> CGFloat{
    return UIScreen.main.bounds.size.width
}

//MARK: - Main Screen Height
func getScreenHeight() -> CGFloat{
    return UIScreen.main.bounds.height
}

Answer 2

viewDidLoad load your ui from storyboard or nib . And size depend on what you select in Interface Builder .

You can initialize ui in viewWillAppear and add a variable isInitialized .

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    if !isInitialized {
        isInitialized = true
        // do your stuff
    }
}

Answer 3

Scroll.contentSize = CGSize（width：self.view.frame.size.width，height：self.view.frame.size.height）

Answer 4

将一个子视图水平居中（使用自动布局约束）到界面构建器中的滚动视图或通过编程方式

Answer 5

Ok so there are a couple of ways you can fix this:

1.- in the storyboard go to your view and you're going to hold the left click in your scroll view and release it over the main view, then you'll click equal width

2.- in the view did load put

self.scrollViewName.frame.size.width = self.view.frame.width

Answer 6

You can set the contentInset on the scrollView, and it will adjust the content size of the scrolling area within the scrollView, here is a quick example

scrollView.contentInset UIEdgeInsets(top: 0, left: 0, bottom: 0, right: padding)

That should do the trick :)

Answer 7

As you are setting constraints from viewDidLoad , but view is not properly layout in this method. You should set constraint when lay out of views is done. So you should set constraints in :

override func viewDidLayoutSubviews() {
    // set constraints here 
}

And you can use a variable to check if constraints are already added.

Answer 8

Try following code, may be you are not able to change frame because of autoresizing, So try to write following code in viewDidAppear method

override func viewDidAppear(_ animated: Bool) {

super.viewDidAppear(animated)

   // Set the frame of scrollview

   self.scrollViewName.frame = CGRectMake(self.scrollViewName.frame.origin.x, 
   self.scrollViewName.frame.origin.y, self.view.frame.size.width, self.view.frame.size.height);

}

Answer 9

Pin your scrollView to view instead of setting its frame .

Add a constraint that sets the width of the contentView equal to the width of the scrollView :

contentView.widthAnchor.constraint(equalTo: scrollView.widthAnchor).isActive = true