Handle delete in empty UITextField

gistfile1.m

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    if ([textField.text length] == 0)
    {
        textField.text = DSEmptyNewLineCharacter;
    }
}

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    // The delete key being pressed always has an NSRange length of one.
    BOOL isDeleteKey = (range.length == 1);
    BOOL isDeletingTheFirstCharacter = (range.location == 0) && (range.length == 1) && (isDeleteKey == YES);

    BOOL firstFieldHasFocus = [textField isEqual:self.firstField];    
    if (firstFieldHasFocus == YES)
    {
        if (isDeletingTheFirstCharacter == YES)
        {
            BOOL fieldHasOnlyEmptyLine = [self.firstField.text isEqual:DSEmptyNewLineCharacter];
            if (fieldHasOnlyEmptyLine == YES)
            {
                [self.firstField resignFirstResponder];
                return NO; 
            }
            else
            {
                self.firstField.text = DSEmptyNewLineCharacter;
                return NO;
            }
        }
        
        [self stripNewLineCharacterIfNecessaryFromField:self.firstField];
    }
}