I have tried 2 more methods. But those are not giving me the correct solution.
If i tried this one

 func textViewDidChange(_ textView: UITextView) {
        self.comments.translatesAutoresizingMaskIntoConstraints = true
        self.comments.sizeToFit()
        self.comments.isScrollEnabled = false
    }

i can only type a one letter per a line.

If i tried this one

 func textViewDidChange(_ textView: UITextView) {
self.comments.translatesAutoresizingMaskIntoConstraints = true
self.comments.isScrollEnabled = false
let fixedWidth = passedOut.frame.size.width
let newSize = comments.sizeThatFits(CGSize(width: fixedWidth, height: CGFloat.greatestFiniteMagnitude))
comments.frame.size = CGSize(width: max(newSize.width, fixedWidth), height: newSize.height)
    }

Its working. But at the viewDidLoad stage, the width of textview is certain less than which i constraints to the textview. But i gave the leading, trailing , height as same as passedOut textfield to that textview.

If i start typing in textview, the width of textview will become exact size which i want.

So pls suggest me what mistake i made?

CodePudding user response：

1. Assign a height constraint to the text view

2. Use the following method to change the height:

    func textViewDidChange(_ textView: UITextView) {
       let size = textView.bounds.size
       let newSize = textView.sizeThatFits(
        CGSize(width: size.width, height: CGFloat.greatestFiniteMagnitude)
       )
   
       if size.height != newSize.height {
           self.userMessageTextViewHeightConstraint.constant = newSize.height
           textView.layoutIfNeeded()
       }
    }
   

CodePudding user response：

You can achieve this behavior by doing 2 things in textview

1. Disable scrolling in textview
2. Assign the following constraints to textview

a) leading

b) trailing

c) top

d) height >= 30 ,assuming 30 is the minimum height of your textview.

Now when your text will grow textview will grow with it.