Keyboard management in iOS Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to dismiss the keyboard when the user taps outside the text field.

iOS Swift

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
  self.view.[1]()
}

Drag options to blanks, or click blank then click option'

AendEditing(true)

BbecomeFirstResponder()

CresignFirstResponder()

DreloadInputViews()

Attempts:

3 left

💡 Hint

Common Mistakes

Using becomeFirstResponder() which actually shows the keyboard.

Using resignFirstResponder() on the view, which is not correct.

Calling endEditing(true) on the view dismisses the keyboard by ending editing on the current first responder.

2fill in blank

medium

Complete the code to move the view up when the keyboard appears.

iOS Swift

NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)

@objc func keyboardWillShow(notification: NSNotification) {
  if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
    self.view.frame.origin.y = [1]
  }
}

Drag options to blanks, or click blank then click option'

A-keyboardSize.height

BkeyboardSize.height

C0

DkeyboardSize.width

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive keyboard height which moves the view down.

Using keyboard width instead of height.

To move the view up, subtract the keyboard height from the view's origin y position.

3fill in blank

hard

Fix the error in the code to reset the view position when the keyboard hides.

iOS Swift

@objc func keyboardWillHide(notification: NSNotification) {
  self.view.frame.origin.y = [1]
}

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Aself.view.frame.origin.y

Bself.view.frame.height

C-self.view.frame.height

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using the view's height which moves the view off screen.

Using negative height which moves the view further up.

Resetting the view's origin y to 0 moves it back to its original position.

4fill in blank

hard

Fill both blanks to add observers for keyboard show and hide notifications.

iOS Swift

NotificationCenter.default.addObserver(self, selector: #selector([1]), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector([2]), name: UIResponder.keyboardWillHideNotification, object: nil)

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AkeyboardWillShow

BkeyboardDidShow

CkeyboardWillHide

DkeyboardDidHide

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Did' notifications which happen after the keyboard animation.

Mixing show and hide selectors incorrectly.

Use keyboardWillShow and keyboardWillHide selectors to respond to keyboard appearance and disappearance.

5fill in blank

hard

Fill all three blanks to properly remove keyboard observers in deinit.

iOS Swift

deinit {
  NotificationCenter.default.[1](self, name: UIResponder.keyboardWillShowNotification, object: nil)
  NotificationCenter.default.[2](self, name: UIResponder.keyboardWillHideNotification, object: nil)
  NotificationCenter.default.[3](self)
}

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AremoveObserver

BaddObserver

Cpost

DremoveAllObservers

Attempts:

3 left

💡 Hint

Common Mistakes

Using addObserver instead of removeObserver.

Trying to call a non-existent removeAllObservers method.

Use removeObserver to unregister from notifications to avoid memory leaks.