Question

How can I set the max string length for a textfield created within a UIAlertView? I am using Xcode 4.5 and building the app on 10.8 (OS X) Currently I have UIAlertView that launches when the user clicks a button. The user will scan their RFID badge, and I want the input textfield of the UIAlertView to be limited to 10 (ten) characters so the user can’t fudge association process.

Answer 1

Looks like the above answer is almost right.

When typing single characters, range.length (for this method) appears to always be zero, while the location increments.

 - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

      NSLog(@"Range: %@", NSStringFromRange(range));
      return ( range.location < 10 );

 }

edit: length would probably be longer if you doing something other than single-character typing, i.e. pasting a line, etc.