Swift 3 move View when keyboard is shown - wrong KeyboardSize - ios

Question

I'm currently struggling with moving my view when iOS is showing/hiding the keyboard.
(Sorry, didn't know how to format code highlighting)
I implemented the following observers:
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
And these functions:
func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y != 0 {
self.view.frame.origin.y += keyboardSize.height/2
}
}
}
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0 {
self.view.frame.origin.y -= keyboardSize.height/2
}
}
}
And I added an extension:
extension UIViewController {
func hideKeyboardWhenTappedAround() {
let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(UIViewController.dismissKeyboard))
tap.cancelsTouchesInView = false
view.addGestureRecognizer(tap)
}
func dismissKeyboard() {
view.endEditing(true)
}
}
So all this together works pretty well.
However, I have a problem once the keyboards thinks it'd be a good idea to show the word suggestions. The keyboard gets higher and the view wanders down too far.
This mostly happens when the users switch from a Numbers-Only keyboard into another textfield where it's a normal keyboard (sometimes with the suggestions).
So, is there a way to know whether the keyboard currently shows the word suggestions (or whatever other 'normal' height divergence)?
I thought about using a global var for the keyboard height of the keyboardWillShow function but that won't work since I'd either move to far or to less when they switch between textfields with different keyboard heights (see number pad).
Any help is highly appreciated! Thanks in advance!
EDIT:
Ah! I think storing the willShowKeyboard-height in a global var and comparing it to the willHideKeyboard-height might work. I'm still open for smoother solutions though!

Answer 1

The key UIKeyboardFrameBeginUserInfoKey doesn't give you the final size - as the name hints "Begin".
Instead try using it's sister UIKeyboardFrameEndUserInfoKey - which will give you the keyboards final size after end animation.
Note it doesn't take rotation into account https://developer.apple.com/reference/uikit/uikeyboardframeenduserinfokey

Answer 2

I ended storing the keyboardHeight from keboardWillShow into a global var and take that variable to move it back in keboardWillHide. And I'm checking whether the last keyboardHeight is equal to the current to move my view if needed.
Not too beautiful. But hey, it works!
// keyboardHeight is a global var.
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0 ||
(keyboardHeight != keyboardSize.height/2)
{
self.view.frame.origin.y = 0
self.view.frame.origin.y -= keyboardSize.height/2
keyboardHeight = keyboardSize.height/2
}
}
}
func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
_ = keyboardSize.height/2 // to surpress warnings...
if self.view.frame.origin.y != 0 {
self.view.frame.origin.y += keyboardHeight //keyboardSize.height/2
}
}
}
I don't know about that self.view.frame.origin.y = 0 in keyboardWillShow. I think I'll consider only moving it the difference instead setting it to 0 each time. But at the moment everythink works as it should.