Numeric text fields in iPhone settings.bundle

I recently checked out this Apple doc: https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/UserDefa开发者_如何学JAVAults/Preferences/Preferences.html

And I can now add settings.bundle into my app and can use it. I can edit Root.plist and I know how to use text fields in this but what I want the user to enter is numeric values.

The default text field allows user to enter any text but I want to take only numeric values from users.

How to do that?

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Simply set keyboard type to number pad. Refer the image below

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I have found the answer myself after surfing the net while and found the answer here:

http://devrichardagreene.blogspot.com/2009/01/creating-user-configurations-on-iphone.html