Why textFieldShouldReturn is still working when i return false?

问题

I am hiding keyboard on return key pressed by implementing function textFieldShouldReturn and calling resignFirstResponder() inside this function. It works perfectly but when I return false in this function, still then keyboard is hiding. Now here I do not understand that what is use of returning true or false if keyboard is hiding in both case?

回答1:

The keyboard is being dismissed due to the call to resignFirstResponder. It has nothing at all to do with the return value of textFieldShouldReturn.

In my experience, the return value of textFieldShouldReturn almost has no use. In the vast majority of cases it makes no difference whether you return true, or false.

I return false in all my uses of testFieldShouldReturn. If you return true and your implementation of textFieldShouldReturn sets the first responder to a UITextView, the text view ends up getting the newline added to it. Returning false from textFieldShouldReturn ensures this won't happen. But this was based on experience with iOS 4 or 5 a few years ago. I don't know if that still happens with the latest versions of iOS.

回答2:

The return value from textFieldShouldReturn answers a different question. If the text field has an action for the control event editingDidEndOnExit, that will cause the keyboard to dismiss unless textFieldShouldReturn is implemented to return false.

回答3:

I have tried that wether true or false, the keyboard do dismiss, here is the code:

func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    textField.resignFirstResponder()
    return false
}

The keyboard do dismiss or not depends on "textField.resignFirstResponder()", if you delete it, the keyboard does no longer dismiss, whether true or false.

来源：https://stackoverflow.com/questions/33624413/why-textfieldshouldreturn-is-still-working-when-i-return-false

标签

ios

uitextfield