UITextView in InputAccessoryView not becoming First Responder (Keyboard does not show up initially)-CodePudding

I'm trying to implement an input accessory view that works just like Messages app in iOS. I've searched almost every SO questions regarding this topic, but couldn't find the solution that worked for me.

Here is the minimal reproducible code I created, referring to this

CodePudding user response：

If you want the text view to become active, and the keyboard to show, as soon as the view appears, use:

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    textView.becomeFirstResponder()
}

If you want the text view to be visible at the bottom, and become active / show the keyboard when the textview is tapped, take a look at this answer:

https://stackoverflow.com/a/61508928/6257435

Edit

If you want to push a view controller onto the navigation stack, and have the keyboard showing with a custom input accessory view, containing a text view, and give it the focus...

Add a hidden text field to the controller. In viewDidLoad tell that text field to use the custom input accessory view and tell it to become first responder.

Then, in viewDidAppear tell the text view in the custom input accessory view to become the first responder:

class TestViewController: UIViewController {
    
    var hiddenTF = UITextField()

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white
        
        // set the text field to hidden
        hiddenTF.isHidden = true
        // add it to the view
        view.addSubview(hiddenTF)

        // tell hidden text field to use custom input accessory view
        hiddenTF.inputAccessoryView = keyboardAccessory
        
        // tell it to become first responder
        hiddenTF.becomeFirstResponder()
    }
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        // tell the textView (in the custom input accessory view)
        //  to become first responder
        textView.becomeFirstResponder()
    }
    
    var textView: UITextView = {
        let view = UITextView()
        view.translatesAutoresizingMaskIntoConstraints = false
        view.backgroundColor = .yellow
        return view
    }()
    
    lazy var keyboardAccessory: UIToolbar = {
        let inputAccessory = UIToolbar(frame: .init(x: 0, y: 0, width: 0, height: 100))
        inputAccessory.addSubview(textView)
        NSLayoutConstraint.activate([
            textView.centerXAnchor.constraint(equalTo: inputAccessory.centerXAnchor),
            textView.centerYAnchor.constraint(equalTo: inputAccessory.centerYAnchor),
            textView.widthAnchor.constraint(equalToConstant: 200),
            textView.heightAnchor.constraint(equalToConstant: 50)
        ])
        inputAccessory.backgroundColor = .gray
        return inputAccessory
    }()
    
}

CodePudding user response：

Actually when you override canBecomeFirstResponder the keyboard is appear just under the view , thats why you only see the accessory view bottom side of the view . You can basically try this with adding notification to your controller like

 override func viewDidLoad() {
    super.viewDidLoad()

    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 func keyboardWillShow(notification:NSNotification) {

    let userInfo = notification.userInfo!
    let keyboardFrame:CGRect = (userInfo[UIResponder.keyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
    print(keyboardFrame)
    print(self.view.frame)
}

When you run the project , you gonna see the keyboardWillShow notification is hired.(If you delete overiride canBecomeFirstResponder it won't )

And when you print keyboard and view frame , you gonna notice to keyboard's y position is equal to view's frame height . That means keyboards want to show us only its accessoryView .

So , you need to hired textView.becomeFirstResponder() in keyboardWillShow notification

@objc func keyboardWillShow(notification:NSNotification) {

    let userInfo = notification.userInfo!
    let keyboardFrame:CGRect = (userInfo[UIResponder.keyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
    textView.becomeFirstResponder()
}

Do not forget to deinit notification when controller deinit

  deinit {
    NotificationCenter.default.removeObserver(self)
}