Want ability to manually scroll to pull textfield above keyboard - ios

Question

The problem is apparently when a user sees that the keyboard is blocking textfields that they want to type in, instead of hitting return, or closing the keyboard and tapping on the next field, they try to pan to the next field. Since my content matches the size of the iPad, the scrollview doesn't automatically scroll when the user tries to pan. Honestly, I don't want it to scroll unless the keyboard is on-screen anyway.
However, enabling scrolling on the scrollview doesn't solve the problem; it still won't respond to panning even in that case. Neither does making the viewcontroller the delegate of the scrollview and overriding the function scrollViewDidScroll. How do I get the scrollview to enable panning, particularly only when the keyboard is enabled?
Since a solution has been posted that doesn't quite work, I think I will post my keyboardWillBeShown and keyboardWillBeHidden code:
func keyboardWillBeShown(_ sender: Notification)
{
self.myScrollView.isScrollEnabled = true
let info: NSDictionary = (sender as NSNotification).userInfo! as NSDictionary
let value: NSValue = info.value(forKey: UIKeyboardFrameBeginUserInfoKey) as! NSValue
let keyboardSize: CGSize = value.cgRectValue.size
let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0)
self.myScrollView.contentInset = contentInsets
self.myScrollView.scrollIndicatorInsets = contentInsets
self.myScrollView.scrollRectToVisible(self.myScrollView.frame, animated: true)
var aRect: CGRect = self.view.frame
aRect.size.height -= keyboardSize.height
let activeTextFieldRect: CGRect? = activeField?.frame
let activeTextFieldOrigin: CGPoint? = activeTextFieldRect?.origin
if activeTextFieldOrigin != nil
{
if (!aRect.contains(activeTextFieldOrigin!))
{
let scrollpoint : CGPoint = CGPoint(x: 0.0, y: activeField!.frame.origin.y - keyboardSize.height)
self.myScrollView.setContentOffset(scrollpoint, animated: true)//.scrollRectToVisible((activeField?.frame)!, animated: true)
}
}
}
func keyboardWillBeHidden(_ sender: Notification)
{
myScrollView.isScrollEnabled = false
let contentInsets: UIEdgeInsets = UIEdgeInsets.zero
myScrollView.contentInset = contentInsets
myScrollView.scrollIndicatorInsets = contentInsets
}

Answer 1

Try this,
Declare variables to be used
var originalViewCGRect: CGRect?
var originalOffset: CGPoint!
in viewDidLoad add keyboard observers
NotificationCenter.default.addObserver(self
, selector: #selector(keyboardWillAppear(_:))
, name: NSNotification.Name.UIKeyboardWillShow
, object: nil)
NotificationCenter.default.addObserver(self
, selector: #selector(keyboardWillDisappear(_:))
, name: NSNotification.Name.UIKeyboardWillHide
, object: nil)
And finally, add these functions
func keyboardWillAppear(_ notification: Foundation.Notification){
self.scrollView.scrollRectToVisible(self.scrollView.frame, animated: true)
let keyboardSize:CGSize = ((notification as NSNotification).userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue.size
let insets = UIEdgeInsetsMake(0, 0, keyboardSize.height, 0)
self.scrollView.contentInset = insets
}
func keyboardWillDisappear(_ notification: Foundation.Notification){
let beginFrame = ((notification as NSNotification).userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
let endFrame = ((notification as NSNotification).userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
let delta = (endFrame.origin.y - beginFrame.origin.y)
self.view.frame = self.originalViewCGRect!
self.scrollView.setContentOffset(CGPoint(x: 0, y: max(self.scrollView.contentOffset.y - delta, 0)), animated: true)
}
In summary, this will adjust the content inset of the scrollview when the keyboard is shown and/or hidden.
Hope this helps.
EDIT
Fixed adjustments

Answer 2

I figured out how to get what I want. Set myScrollView.contentSize to be as big as the screen plus the keyboard when the keyboard is shown, and reduce the size back to what it was when keyboard is hidden. Then make the view controller a UIScrollViewDelegate, set myScrollView.delegate = self, and implement scrollViewDidScroll so that if a textfield is editing, and that textfield isn't blank, then change which text field is the first responder. Piece of cake once you realize the trick of setting .contentSize!