Maintaining reference to UITextField "text" field - objective-c

Question

Problem:
I am trying to create a custom UITextField class "UIValidatedTextField" which allows one to set certain rules as to whether input is valid. For example, you can set a regex parameter to ensure that input is of a specific format, i.e. a password, email address, etc...
Another ability of this is to specify and set a parameter that references another UITextField and ensures that the input matches the input from that other UITextField.
The issue I am having here, is that I am setting this reference to another UITextField. However, when I access its "text" field I find that there is nothing in the text field even when I type something into it.
I have provided related code below:
#import "UIRegisterViewController.h"
#import "UIRegisterViewCell.h"
#import "UIValidatedTextField.h"
#import "NSConstants.h"
#interface UIRegisterViewController ()
#end
#implementation UIRegisterViewController
- (void)viewDidLoad {
[super viewDidLoad];
_tableView.delegate = self;
_tableView.dataSource = self;
_tableItems = #[#"name", #"email", #"netId", #"username", #"password", #"confirmPassword"];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [_tableItems count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSString *cellIdentifier = [_tableItems objectAtIndex:indexPath.row];
UIRegisterViewCell *cell = [_tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
if ([cellIdentifier isEqualToString:#"email"]) {
[cell.textField setRegex:VALID_DUKE_EMAIL_REGEX];
} else if ([cellIdentifier isEqualToString:#"netId"]) {
//Validation?
} else if ([cellIdentifier isEqualToString:#"username"]) {
//Validation?
//THIS IS THE CELL THAT I WANT TO COMPARE INPUT TO
} else if ([cellIdentifier isEqualToString:#"password"]) {
[cell.textField setRegex:VALID_PASSWORD_REGEX];
//SETTING THE TEXT FIELD IN QUESTION HERE...
} else if ([cellIdentifier isEqualToString:#"confirmPassword"]) {
[cell.textField setRegex:VALID_PASSWORD_REGEX];
NSIndexPath *index = [NSIndexPath indexPathForRow:4 inSection:0];
UIRegisterViewCell *confirm =(UIRegisterViewCell *)[self tableView:_tableView cellForRowAtIndexPath:index];
[cell.textField setConfirm:confirm.textField];
}
cell.textField.delegate = self;
return cell;
}
#pragma mark - Text Field Delegate
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
[textField resignFirstResponder];
return YES;
}
#end
Note that the textFields are UIValidatedTextFields - a custom class provided below:
#import "UIValidatedTextField.h"
#import "NSArgumentValidator.h"
#implementation UIValidatedTextField
- (id) initWithCoder:(NSCoder *)aDecoder {
self = [super initWithCoder:aDecoder];
if (self) {
[self initialize];
}
return self;
}
- (id)initialize {
if (self) {
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(textFieldDidChange:)
name:UITextFieldTextDidChangeNotification object:self];
[self validate]; //Validate in case editing began before observer was set.
}
return self;
}
- (void) setOptional:(BOOL)isOptional {
_isOptional = isOptional;
}
- (BOOL) isOptional {
return _isOptional;
}
- (void) setRegex:(NSString *)regex {
_regex = regex;
}
//SET THE TEXT FIELD TO COMPARE INPUT AGAINST HERE.
- (void) setConfirm:(UITextField *)confirm {
_confirm = confirm;
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(textFieldDidChange:)
name:UITextFieldTextDidChangeNotification object:_confirm];
[self validate]; //Validate in case editing on confirm began before observer was set.
}
- (void) setQuery:(NSString *)query {
_query = query;
}
- (void) textFieldDidChange:(NSNotification *)notification {
NSLog(#"UPDATE");
_isValid = [self validate];
[self showInputValidation];
}
- (BOOL) validateRegex {
if (_regex.length == 0) {
return true;
}
return [NSArgumentValidator isValid:self.text withRegex:_regex];
}
- (BOOL) validateConfirm {
// NSLog(#"%# : %#", [_confirm text], self.text);
if (_confirm == NULL) {
//NSLog(#"IS NULL");
return true;
}
return [self.text isEqualToString:_confirm.text];
}
- (BOOL) validateQuery {
return true;
}
- (BOOL) validate {
_isValid = (self.text == 0 && _isOptional) || ((self.text != 0) && [self validateRegex] && [self validateConfirm] && [self validateQuery]);
return _isValid;
}
//IF ANYONE HAS A SOLUTION AS TO HOW TO MAKE CHANGING BORDER COLOR CHANGE THE COLOR ALONG THE ROUNDED BORDER THAT IS PRESENT AS OPPOSED TO A RECTANGULAR BORDER LET ME KNOW.
- (void) showInputValidation {
self.layer.borderWidth = 1.0;
if (self.text.length == 0) {
self.layer.borderColor = [[UIColor blackColor] CGColor];
} else if (_isValid) {
self.layer.borderColor = [[UIColor greenColor] CGColor];
} else {
self.layer.borderColor = [[UIColor redColor] CGColor];
}
}
- (void) finalize {
[super finalize];
[[NSNotificationCenter defaultCenter] removeObserver:self
name:UITextFieldTextDidChangeNotification object:self];
if (_confirm != NULL) {
[[NSNotificationCenter defaultCenter] removeObserver:self
name:UITextFieldTextDidChangeNotification object:_confirm];
}
}
#end
Thanks for the help!

Answer 1

One glaring bug in this code is that you're setting the regex in cellForRowAtIndexPath:, even though all cell are reusing the same cell object. cellForRowAtIndexPath: should be used only to set cell content, like text and color. Instead, create an IBOutlet to the validating text fields and add their regexes in viewDidLoad. Better yet, scrap the custom subclass entirely and instead run your regex validation whenever one of the relevant text fields fires off an event when editing is finished.