ScrollView and keyboard in Swift
Solution 1:
In ViewDidLoad, register the notifications:
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name:UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name:UIResponder.keyboardWillHideNotification, object: nil)
Add below observer methods which does the automatic scrolling when keyboard appears.
@objc func keyboardWillShow(notification:NSNotification) {
guard let userInfo = notification.userInfo else { return }
var keyboardFrame:CGRect = (userInfo[UIResponder.keyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
keyboardFrame = self.view.convert(keyboardFrame, from: nil)
var contentInset:UIEdgeInsets = self.scrollView.contentInset
contentInset.bottom = keyboardFrame.size.height + 20
scrollView.contentInset = contentInset
}
@objc func keyboardWillHide(notification:NSNotification) {
let contentInset:UIEdgeInsets = UIEdgeInsets.zero
scrollView.contentInset = contentInset
}
Solution 2:
The top answer for swift 3:
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name:NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name:NSNotification.Name.UIKeyboardWillHide, object: nil)
And then:
func keyboardWillShow(notification:NSNotification){
//give room at the bottom of the scroll view, so it doesn't cover up anything the user needs to tap
var userInfo = notification.userInfo!
var keyboardFrame:CGRect = (userInfo[UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
keyboardFrame = self.view.convert(keyboardFrame, from: nil)
var contentInset:UIEdgeInsets = self.theScrollView.contentInset
contentInset.bottom = keyboardFrame.size.height
theScrollView.contentInset = contentInset
}
func keyboardWillHide(notification:NSNotification){
let contentInset:UIEdgeInsets = UIEdgeInsets.zero
theScrollView.contentInset = contentInset
}
Solution 3:
Here is a complete solution, utilizing guard and concise code. Plus correct code in keyboardWillHide
to only reset the bottom
to 0.
@IBOutlet private weak var scrollView: UIScrollView!
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
registerNotifications()
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
scrollView.contentInset.bottom = 0
}
private func registerNotifications() {
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 private func keyboardWillShow(notification: NSNotification){
guard let keyboardFrame = notification.userInfo![UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else { return }
scrollView.contentInset.bottom = view.convert(keyboardFrame.cgRectValue, from: nil).size.height
}
@objc private func keyboardWillHide(notification: NSNotification){
scrollView.contentInset.bottom = 0
}
Solution 4:
for Swift 4.0
In ViewDidLoad
// setup keyboard event
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)
Add below observer methods which does the automatic scrolling when keyboard appears.
@objc func keyboardWillShow(notification:NSNotification){
var userInfo = notification.userInfo!
var keyboardFrame:CGRect = (userInfo[UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
keyboardFrame = self.view.convert(keyboardFrame, from: nil)
var contentInset:UIEdgeInsets = self.ui_scrollView.contentInset
contentInset.bottom = keyboardFrame.size.height
ui_scrollView.contentInset = contentInset
}
@objc func keyboardWillHide(notification:NSNotification){
let contentInset:UIEdgeInsets = UIEdgeInsets.zero
ui_scrollView.contentInset = contentInset
}