Changing the frame of an inputAccessoryView in iOS 8

Question

Long time lurker - first time poster!

I am having an issue while recreating a bar with a UITextView like WhatsApp does it.

I am using a custom <

Answer 1

To sum up JohnnyC's answer: set your inpitAccessoryView's autoresizingMask to .flexibleHeight, calculate its intrinsicContentSize and let the framework do the rest.

Full code, updated for Swift 3:

class InputAccessoryView: UIView, UITextViewDelegate {

    let textView = UITextView()

    override var intrinsicContentSize: CGSize {
        // Calculate intrinsicContentSize that will fit all the text
        let textSize = textView.sizeThatFits(CGSize(width: textView.bounds.width, height: CGFloat.greatestFiniteMagnitude))
        return CGSize(width: bounds.width, height: textSize.height)
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        // This is required to make the view grow vertically
        autoresizingMask = .flexibleHeight

        // Setup textView as needed
        addSubview(textView)
        textView.translatesAutoresizingMaskIntoConstraints = false
        addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[textView]|", options: [], metrics: nil, views: ["textView": textView]))
        addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[textView]|", options: [], metrics: nil, views: ["textView": textView]))

        textView.delegate = self

        // Disabling textView scrolling prevents some undesired effects,
        // like incorrect contentOffset when adding new line,
        // and makes the textView behave similar to Apple's Messages app
        textView.isScrollEnabled = false
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    // MARK: UITextViewDelegate

    func textViewDidChange(_ textView: UITextView) {
        // Re-calculate intrinsicContentSize when text changes
        invalidateIntrinsicContentSize()
    }

}