calculating keyboard height without using NSNotification in swift - swift

Question

I have a very small question - can we calculate the Keyboard Height with out using Notification. All the answers in stake overflow is using NSNotification but is there simpler way of calculating it?
below is the code:
NotificationCenter.default.addObserver( self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil
#objc func keyboardWillShow(notification: ) {
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
let kbHeight = keyboardSize.height
}
}
}
Code to use keyboard height in textFieldDidBeginEditing:
var kbHeight: CGFloat?
#objc func keyboardWillShow(notification: NSNotification) {
if let userInfo = notification.userInfo {
if let keyboardSize = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
kbHeight = keyboardSize.height
}
}
}
func textFieldDidBeginEditing(_ textField: UITextField) {
if textField.frame.maxY > self.kbHeight!
{
self.scrollView.setContentOffset(CGPoint.init(x: 0, y: textField.frame.maxY - (self.kbHeight! + 2.0)), animated: true)
}
else{
return
}
print(textField.frame.maxY)
print(self.view.frame.height * 0.6)
print(textField.frame.maxY - self.view.frame.height * 0.6)
}
func textFieldDidEndEditing(_ textField: UITextField)
{
self.scrollView.setContentOffset(CGPoint.init(x: 0, y: 0), animated: true)
self.view.endEditing(true);
}

Answer 1

actually i don't have any idea for getting keyboard hight directly.. but you can save the keyboard height in variable when keyboard is present and use them where you want
Use these two Observers for keyboard and manage the keyboard hight
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)
Must be remove these observer at dinit method when pop or dismiss the view controller.
deinit {
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
Selector methods for keyboard notification ...
#objc func keyboardWillShow(notification: NSNotification) {
var keyBoardHeight: CGFloat = 0
if let keyboardFrame: NSValue = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue {
let keyboardRectangle = keyboardFrame.cgRectValue
keyBoardHeight = keyboardRectangle.height
}
}
#objc func keyboardWillHide(notification: NSNotification) {
}