Making a uitextfield scroll to the bottom when adding an item - ios

Question

I have a collectionViewController and an inputContainerAccesoryView that have a uitextfield inside. Every time I press return on the keyboard, an item (a row) is added to the collectionview, and I want the collectionview to automatically scroll to the bottom of it; also I want that when the keyboard shows up, it also scrolls to the bottom of the collectionview. I have a tried a code, but is not scrolling the way I want:
viewDidLoad
collectionView?.keyboardDismissMode = .interactive
NotificationCenter.default.addObserver(
self,
selector: #selector(HomeViewController.keyboardWillShow(event:)),
name: NSNotification.Name.UIKeyboardWillShow,
object: nil
)
textFieldShouldReturn
handleKeyboardDidShow()
The methods
func keyboardWillShow(event: Notification) {
//let keyboardqlq = inputTextField.frame.height
guard let keyboardFrame = (event.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else { return }
guard let colelctionview = self.collectionView else { return }
colelctionview.contentInset.bottom = keyboardFrame.height - 200
colelctionview.scrollIndicatorInsets.bottom = keyboardFrame.height - 200
// do NOT scroll messages if the keyboard is the `accessoryView`
if keyboardFrame.height != inputContainerView.frame.height {
handleKeyboardDidShow()
}
}
func handleKeyboardDidShow() {
if messages.count > 0 {
let indexPath = IndexPath(item: messages.count - 1, section: 0)
collectionView?.scrollToItem(at: indexPath, at: .bottom, animated: true)
}
}

Answer 1

Maybe it's not efficient but it solves the problem. Make sure that textfield delegate is self.
var needToScroll :Bool = true
func textFieldDidBeginEditing(_ textField: UITextField) {
needToScroll = true
}
func handleKeyboardWillHide(notification:Notification) {
let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
UIView.animate(withDuration: keyboardDuration!) {
self.view.layoutIfNeeded()
self.chatLogCollectionView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 30, right: 0)
self.needToScroll = false
}
}
func handleKeyboardWillShow(notification:Notification) {
let keyboardFrame = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? CGRect
let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
UIView.animate(withDuration: keyboardDuration!) {
self.view.layoutIfNeeded()
self.chatLogCollectionView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: (keyboardFrame?.height)!, right: 0)
if self.needToScroll {
if self.chatLogCollectionView.messages.count > 0 {
self.chatLogCollectionView.scrollToItem(at: NSIndexPath(item: self.chatLogCollectionView.messages.count - 1, section: 0) as IndexPath, at: .bottom, animated: false)
}
}
}
}