Calling a method on every edit of UITextField - ios

Question

I'm now programming a simple app that has 3 UITextFields and if I edit one, the other two should scale together with it.
I tried using
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
this method, but:
replacement string is the last character that was typed in
can't figure out how backspace works there
it is being called a little too early
if I can "fix" the first point(by sending
[NSString stringWithFormat:#"%#%#", [textField text], string];
as a parameter), it will not "fix" the second point, because string variable is:
(lldb) po string
(NSString *) $1 = 0x0080cf14 <object returned empty description>
So the question is: is there any method that is being called AFTER textFieldShouldChangeCharactersInRange:? Or is there a way to:
return YES in textFieldShouldChangeCharactersInRange: method
and THEN call a method to change the values of the 2 other UITextFields?
EDIT
I could use the following:
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
[self performSelector:#selector(myMethod:) withObject:textField afterDelay:0.1];
return YES;
}
but it doesn't seem to be the safest solution

Answer 1

The backspace works modifying the NSRange with a empty string. What you can do is modify the three text field in the textField:shouldChange and then return NO to the method.
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
textField.text = [textField.text stringByReplacingCharactersInRange:range withString:string]; // this is what will happen if you return yes to this method
anotherTextField.text = // do whatever u need
yetAnotherTextField.text = // do whatever u need
return NO;
}

Answer 2

The following code prints correctly the full text of the text view (with the last character that was inserted), can that be useful?
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
if ([string length])
NSLog(#"Current Text:%#", [textField.text stringByAppendingString:string]);
else
NSLog(#"Current Text:%#", [textField.text substringWithRange:(NSRange){0, [textField.text length]-1}]);
return YES;
}
The backspace just sends an empty string in the string parameter.

Answer 3

For textFields:
[yourtextField addTarget:self action:#selector(textFieldDidChange) forControlEvents:UIControlEventEditingChanged];
-(void)textFieldDidChange
{
//Your Code
}