iphone - A way to tell when the user is done typing on a timed interval? -

I'm wondering if there is a way that the user should ask for UITextField for 2 seconds

If this is not possible, then I want to know if there is any way to tell that the user has typed an error in the text field - Example:

Code> UITextView which contains objects from NSArray and the user will need to type in the textfield and the content on the text view. Must match. If they make a mistake, they will tell them (I need help) - Note: If the user correctly typed the string, then it automatically accepts it and goes to the next one - string There is no button to submit - it does that through a text field.

Wherever you are handling the change of text, you can see a NSTimer . If more text is entered before the timer's fire, then you can call it at -invalidate to cancel it, but if the timer sets the fire, then you do not know if anyone The text has not been entered.