fixed conversion warning

gistfile1.m

#pragma mark - Phone Number Field Formatting

// Adopted from: http://stackoverflow.com/questions/6052966/phone-number-formatting
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if (textField == self.mobileNumberField || textField == self.homeNumberField || textField == self.workNumberField) {
        int length = [self getLength:textField.text];
        
        if(length == 10) {
            if(range.length == 0)
                return NO;
        }
        
        if(length == 3) {
            NSString *num = [self formatNumber:textField.text];
            textField.text = [NSString stringWithFormat:@"(%@) ",num];
            if(range.length > 0)
                textField.text = [NSString stringWithFormat:@"%@",[num substringToIndex:3]];
        }
        else if(length == 6) {
            NSString *num = [self formatNumber:textField.text];
            textField.text = [NSString stringWithFormat:@"(%@) %@-",[num  substringToIndex:3],[num substringFromIndex:3]];
            if(range.length > 0)
                textField.text = [NSString stringWithFormat:@"(%@) %@",[num substringToIndex:3],[num substringFromIndex:3]];
        }
    }
    return YES;
}

-(NSString*)formatNumber:(NSString*)mobileNumber
{
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"(" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@")" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@" " withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"-" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"+" withString:@""];
    
    NSUInteger length = [mobileNumber length];
    if(length > 10) {
        mobileNumber = [mobileNumber substringFromIndex: length-10];
    }
    return mobileNumber;
}


-(int)getLength:(NSString*)mobileNumber
{
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"(" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@")" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@" " withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"-" withString:@""];
    mobileNumber = [mobileNumber stringByReplacingOccurrencesOfString:@"+" withString:@""];
    
    int length = [mobileNumber length];
    return length;
}