How to handle Tab key press in iOS?

Question

I have a UIViewController which has 3 three UITextFields - TF1, TF2 and TF3. When the app is running on iOS simulator and I press Tab key, the focus moves to the next text field as expected.

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TF3 is special. When the user taps on TF3, the text field should not get focused but instead a new view must be shown on the screen. I have implemented the UITextFieldDelegate method textFieldShouldBeginEditing(_:) to fix this as follows-

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
    if (textField == TF3) {
        // show new view
        return false
    }
    return true
}

This works as expected.

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After the above code is added, whenever the Tab key is pressed, the new view is shown. This is because whenever the Tab key is pressed, textFieldShouldBeginEditing(_:) is called on all the text fields on the screen.

Consider that TF1 is the first responder at present.

If I press Tab key, it moves the focus to TF2 as expected. However, the new view is also shown because textFieldShouldBeginEditing(_:) is called on TF3.

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Can anyone point out how to solve this issue?

Answer 1

if I understand you correctly,what you want is below:

Plan A

var isTF3Beginned = false // a property of current view controller as flag

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
    if (textField == TF3 && isTF3Beginned == true) {
        // show new view
        return false
    }
    isTF3Beginned = true
    return true
}

Plan B RxSwift

TF3.rx
.controlEvent(.editingDidBegin)
.skip(1)
.subscribe(onNext: { () in
    // show new view
}).disposed(by: disposeBag)