Handling keyboard with bottom constraint - ios

Question

I'm building a chat app with a regular design and UI of a chat app.
I have a "toolbar" that my app needs (0,0 375x66) and I want it to stay where it is when the keyboard is shown. It has 4 constraints: top: 0, leading: 0, trailing: 0, aspect-ratio: 125:22
I have a UICollectionView (0,66 375x530) that I want to be scrolled like any other chat app when the keyboard is shown. It has 4 constraints: top (to the toolbar): 0, leading: 0, trailing: 0, bottom (to the newMessageView I'll explain shortly): 0
I have a UIView that has a UITextField inside it. let's call it newMessageView (0,596 375x71) and it has 4 constraints: bottom: 0, leading: 0, trailing: 0, aspect-ratio: 375:71
Now, I'm trying to bring the newMessageView app when the keyboard is shown. I'm trying to to it like this:
#objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y == 0{
self.newMessageViewBottomConstraint.constant += keyboardSize.height
}
}
}
#objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
if self.view.frame.origin.y != 0{
self.newMessageViewBottomConstraint.constant -= keyboardSize.height
}
}
}
but it completly doesn't work. The view jumps and hides and I really can't understand why.
Am I doing it right? Can anyone help me and guide me with this?

Answer 1

You have to use self.view.layoutIfNeeded() after Update constraint
i write complete solution for you
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
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)
}
#objc func keyboardWillShow(notification: Notification) {
self.keyboardControl(notification, isShowing: true)
}
#objc func keyboardWillHide(notification: Notification) {
self.keyboardControl(notification, isShowing: false)
}
private func keyboardControl(_ notification: Notification, isShowing: Bool) {
/* Handle the Keyboard property of Default*/
var userInfo = notification.userInfo!
let keyboardRect = (userInfo[UIKeyboardFrameEndUserInfoKey]! as AnyObject).cgRectValue
let curve = (userInfo[UIKeyboardAnimationCurveUserInfoKey]! as AnyObject).uint32Value
let convertedFrame = self.view.convert(keyboardRect!, from: nil)
let heightOffset = self.view.bounds.size.height - convertedFrame.origin.y
let options = UIViewAnimationOptions(rawValue: UInt(curve!) << 16 | UIViewAnimationOptions.beginFromCurrentState.rawValue)
let duration = (userInfo[UIKeyboardAnimationDurationUserInfoKey]! as AnyObject).doubleValue
var pureheightOffset : CGFloat = -heightOffset
if isShowing { /// Wite space of save area in iphonex ios 11
if #available(iOS 11.0, *) {
pureheightOffset = pureheightOffset + view.safeAreaInsets.bottom
}
}
// Here change you Consrant
// self.actionBarPaddingBottomConstranit?.update(offset:pureheightOffset)
UIView.animate(
withDuration: duration!,
delay: 0,
options: options,
animations: {
self.view.layoutIfNeeded()
},
completion: { bool in
})
}