How to change the TextView height dynamicly to a threshold and then allow scrolling?

Question

I have a TextView that has a constraint of min height of 33. The scroll is disabled from the storyboard. The TextView should increase in height based on the content until it

Answer 1

For an easy way to solve your problem is to change the frame of the textView whenever textViewDidChange invokes. UITextView actually is a UIScrollView. If you have to use constraint, you have to change the constant of the constraint. Here is my code:

import UIKit

let width = UIScreen.mainScreen().bounds.width

class ViewController: UIViewController, UITextViewDelegate {

    var messageTextView: UITextView!
    let messageTextViewMaxHeight: CGFloat = 100

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = UIColor.redColor()
        messageTextView = UITextView(frame: CGRectMake(0, 200 - 33, width, 33))
        messageTextView.backgroundColor = UIColor.whiteColor()
        view.addSubview(messageTextView)
        self.messageTextView.delegate = self
    }

    //
    let bottomY: CGFloat = 200

    func textViewDidChange(textView: UITextView) {
        let formerRect = textView.frame

        if formerRect.height > messageTextViewMaxHeight{

        }
        else{
            textView.frame = CGRectMake(formerRect.origin.x, bottomY - textView.contentSize.height, width, textView.contentSize.height)
        }
    }
}