NumberPad restrict numeric input

Question

Hi,

I have some simple UITextFields that bring up the Numberpad.

I would like to restrict the control the user has over input.

For example, one particular textField should not been allowed any value over 32.

Which parameter do I use with <32 to enable this?

Thanks

Answer 1

You could use

[aTextfield.text intValue] < 32

to compare the text in the Textfield to 32. ;-)

Answer 2

I would implement this UITextFieldDelegate method:

- (BOOL) textField: (UITextField *) textField shouldChangeCharactersInRange: (NSRange) range replacementString: (NSString *) string
{
    NSString *result = [textField.text stringByReplacingCharactersInRange: range withString: string];
    if ( [result intValue] < 0 || [result intValue] > 32 )
        return NO;
    return YES;
}

For consistency, you may also want to implement -textFieldShouldEndEditing: to return false when the value is invalid.