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

Here's a complete, self-contained solution (thanks @JohnnyC and @JoãoNunes for pointing me in the right direction, @stigi for explaining how to animate intrinsicContent changes):

class InputAccessoryView: UIView {

    // InputAccessoryView is instantiated from nib, but it's not a requirement
    override func awakeFromNib() {
        super.awakeFromNib()        
        autoresizingMask = .FlexibleHeight
    }

    override func intrinsicContentSize() -> CGSize {
        let exactHeight = // calculate exact height of your view here
        return CGSize(width: UIViewNoIntrinsicMetric, height: exactHeight)
    }

    func somethingDidHappen() {
        // invalidate intrinsic content size, animate superview layout        
        UIView.animateWithDuration(0.2) {
            self.invalidateIntrinsicContentSize()
            self.superview?.setNeedsLayout()
            self.superview?.layoutIfNeeded()
        }
    }
}