Question

I am creating a multi-user iPhone app, and I am trying to finish up the coding for the user login in process. I can successfully create an account, and store the data the user inputs into the Core Data DB, and the pin into the Keychain, so now I am trying to complete the login process. The following code listed below is what I have so far, I am getting an error, No visible @interface for ‘Account’ declares the selector ‘password:’

- (IBAction)processLogin:(id)sender {

// hide keyboard
[_textFieldUsername resignFirstResponder];
[_textFieldPin resignFirstResponder];


// First - make activity indicator visible, then start animating, then turn of wrong user / pin label
_welcomeActivityIndicator.hidden = FALSE;
[_welcomeActivityIndicator startAnimating];
[_wrongUserPin setHidden:YES];

// check if username and pin text fields are populated
if ([_textFieldUsername.text length ] == 0 &&  [_textFieldPin.text length ] == 0)
{
    [_welcomeActivityIndicator stopAnimating];
    [_wrongUserPin setHidden:NO];   
}

// CORE DATA
// NSManagedObjectContext *context = _managedObjectContext;

NSFetchRequest *request= [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Account" inManagedObjectContext:_managedObjectContext];
NSPredicate *predicate =[NSPredicate predicateWithFormat:@"username=%@",self.textFieldUsername.text];

// TODO check pin
Account *pinAccount = [[Account alloc] init];

// GETTING ERROR ON BELOW LINE OF CODE! - ERR0R - No visible @interface for 'Account' declares the selector 'password:'
[pinAccount password:_textFieldPin.text];


[request setEntity:entity];
[request setPredicate:predicate];

NSError *error = nil;

NSArray *array = [_managedObjectContext executeFetchRequest:request error:&error];
if (array != nil) {
    NSUInteger count = [array count]; // may be 0 if the object has been deleted.
    NSLog(@"Username may exist, %@",count);
}

else {
    NSLog(@"Username does not exist.");
}
}

The Account class files m and h look like the following:

Account.m

- (NSString*)password 
{
if (self.username)
    return [KeychainHelper getPasswordForKey:self.username];
return nil;
}

- (void)setPassword:(NSString*)aPassword 
{
if (self.username) [KeychainHelper setPassword:aPassword forKey:self.username];


}
- (void)prepareForDeletion
{
if (self.username) [KeychainHelper removePasswordForKey:self.username];
}
@end

Account.h

#import "AccountBase.h"

@interface Account : AccountBase {

}

// nonatomic - don't worry about multithreading

@property (nonatomic, assign) NSString *password;

- (void)setPassword:(NSString*)aPassword;

@end

I would appreciate any ideas or thoughts, and thanks for reading.

Answer 1

I was able to check / verify the pin with the following code.

// CORE DATA
NSFetchRequest *request = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Account" inManagedObjectContext:_managedObjectContext];

// set entity for request
[request setEntity:entity];

// filter results using a predicate
NSPredicate *pred =[NSPredicate predicateWithFormat:(@"username = %@"), _textFieldUsername.text];

// set predicate for the request
[request setPredicate:pred];

NSError *error = nil;

// store DB usernames in results array
NSArray *results = [_managedObjectContext executeFetchRequest:request error:&error];

NSLog(@"The returned results are %@",results);


// check text field against results stored in DB
for (Account *anAccount in results) {
    if ([anAccount.username isEqualToString:_textFieldUsername.text]){
        NSLog(@"Your username exists");
        if ([anAccount.password isEqualToString:_textFieldPin.text]){
            NSLog(@"Your pin is correct");