Global variable value issue iPhone

Question

I have declared a variable NSString sessionId; in app delegate file for global usage.

In appdelegate.h

@property (strong, nonatomic) NSMutableString *sessionId;

In appdelegate.m

@synthesize sessionId;

And used it in one of my view controller like this.

    ((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId = sID.retain;

NSLog(@"session id = %@", ((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId);

I am able to accèss that variable sessionId in all of my view controllers but the issue is that the value is not getting saved in it. Like in viewcontroller1.m, I assigned it some value but when I accessed sessionId in another viewcontroller2.m, its showing its value as null on console.

How can I resolve this issue.

Code added:

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
     NSString *responseString = [[NSString alloc] initWithData:receivedData encoding:NSUTF8StringEncoding];

self.receivedData = nil;


    NSError *error;

    SBJSON *json = [[SBJSON new] autorelease];

    NSArray *session = [json objectWithString:responseString error:&error];

    SBJsonParser *parser =[[SBJsonParser alloc] init];

    NSDictionary *jsonObject = [parser objectWithString:responseString];

    sID = [jsonObject objectForKey:@"session"];

    ((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId = sID;

    NSLog(@"session id = %@", ((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId);


    NSUserDefaults *sessID = [NSUserDefaults standardUserDefaults];

    [sessID setObject:sID forKey:@"sessionID"];

    [sessID synchronize];

    NSLog(@"This session %@ saved", sID);

    NSDictionary *accountsObj = [parser objectWithString:responseString];

    NSString *accounts = [accountsObj objectForKey:@"account"];

    NSArray *accountList = [accounts componentsSeparatedByString:@","];

    NSLog(@"Accounts: %@", accountList);


    if (session == nil)
    NSLog(@"JSON parsing failed: %@", [error localizedDescription]);
else {

    if (accountList.count > 1) {

        ChooseAccountsController *accountsView = [[ChooseAccountsController alloc] initWithNibName:@"ChooseAccountsController" bundle:nil ];

        self.chooseAcc = accountsView;

        [self.view addSubview: accountsView.view];
    } else if (accountList.count == 1) {

            MainScreenController *mainScreen1 = [[MainScreenController alloc] initWithNibName:@"MainScreen" bundle:nil ];

             self.mainScreen = mainScreen1;

             [self.view addSubview: mainScreen1.view];

         }
    }

}

Well, show us how you did declare the variable in the first place, please. — cli_hlt
man, your variable naming is horrible! why do you assign your user defaults to an name sessID? — vikingosegundo
before getting into application delegate variable stuff, I was thinking of nsuserdefaults to save the sessionId, thats y — user831679
I don't see, why you need this property on your AppDelegate. Just write and read it to/from your [NSUserDefaults standardUserDefaults] where needed. — vikingosegundo
was just gonna try it... but didn't used it... now I have deleted it .. if the solution you have suggested will work fine then I don't need another method ... but still I am getting issue of variable values getting null sometimes and sometimes not ... this abnormal behavior is very bad .. — user831679

vikingosegundo vikingosegundo · Accepted Answer · 2012-01-02T13:05:01

((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId = sID.retain;

is not valid code, try

((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId = sID

a strong property should be retaining, and also retain is a message, so if you need this (not in this case) the only correct syntax is [anObject retain]

try

((VektorAppDelegate *)[UIApplication sharedApplication].delegate).sessionId = [jsonObject objectForKey:@"session"];

Global variable value issue iPhone

4 Answers