objective c - How to re-size UITextView when keyboard shown with iOS 7

Question

I have a view controller which contains a full-screen UITextView. When the keyboard is shown I would like to resize the text view so that it is not hidden under the keyboard.

This is a fairly standard approach with iOS, as described in this question:

How to resize UITextView on iOS when a keyboard appears?

However, with iOS 7, if the user taps on the text view in the bottom half of the screen, when the text view resizes, the cursor remains offscreen. The text view only scrolls to bring the cursor into view if when the user hits enter.

Answer 1

I read the docs which talk about this very topic. I translated it into Swift and it worked absolutely beautifully for me.

This is used for a full page UITextView like iMessage.

I am using iOS 8.2 and Swift on XCode 6.2 and here's my code. Just call this setupKeyboardNotifications from your viewDidLoad or other initialization method.

func setupKeyboardNotifications() {
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWasShown(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    let contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0)
    codeTextView.contentInset = contentInsets
    codeTextView.scrollIndicatorInsets = contentInsets
}

func keyboardWillBeHidden(aNotification:NSNotification) {
    let contentInsets = UIEdgeInsetsZero
    codeTextView.contentInset = contentInsets
    codeTextView.scrollIndicatorInsets = contentInsets
}

Also if you are having issues with the caret being in the right place when rotated check for the orientation change and scroll to the right position.

override func didRotateFromInterfaceOrientation(fromInterfaceOrientation: UIInterfaceOrientation) {
    scrollToCaretInTextView(codeTextView, animated: true)
}

func scrollToCaretInTextView(textView:UITextView, animated:Bool) {
    var rect = textView.caretRectForPosition(textView.selectedTextRange?.end)
    rect.size.height += textView.textContainerInset.bottom
    textView.scrollRectToVisible(rect, animated: animated)
}

Swift 3:

func configureKeyboardNotifications() {
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(aNotification:)), name: NSNotification.Name.UIKeyboardDidShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(aNotification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

func keyboardWasShown(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as! NSValue
    let kbSize = infoNSValue.cgRectValue.size
    let contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0)
    textView.contentInset = contentInsets
    textView.scrollIndicatorInsets = contentInsets
}

func keyboardWillBeHidden(aNotification:NSNotification) {
    let contentInsets = UIEdgeInsets.zero
    textView.contentInset = contentInsets
    textView.scrollIndicatorInsets = contentInsets
}

Swift 4 & 5:

func setupKeyboardNotifications() {
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_ :)), name: UIResponder.keyboardWillShowNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
}



@objc func keyboardWillShow(_ notification:NSNotification) {
    let d = notification.userInfo!
    var r = (d[UIResponder.keyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
    r = self.textView.convert(r, from:nil)
    self.textView.contentInset.bottom = r.size.height
    self.textView.verticalScrollIndicatorInsets.bottom = r.size.height

}

@objc func keyboardWillHide(_ notification:NSNotification) {
    let contentInsets = UIEdgeInsets.zero
    self.textView.contentInset = contentInsets
    self.textView.verticalScrollIndicatorInsets = contentInsets
}