Question

I’ve got an App with different ViewControllers which are managed in an Navigation Controller. In one ViewController I’m making a Request to my WebService to authenticate the user. I’m writing the respond in an BOOL (isLoggedIn). Now I need to use this BOOL and the username in different ViewControllers. I need the variable to change a Custom Navigation Button Title (Login -> Logout). Also in an other ViewController I’ve to send something to my WebService, but only an Authenticated User (isLoggedIn) is permitted to make the call.
I hope it’s well enough explained 🙂
So what possibilites do I have to make this work? I’ve read something to create a Singleton Class, is this the proper way?

Or should I make somehow a connection from my LoginViewController to the affected ViewControllers?
How can I do this? Right now I’ve just used the method prepareForSegue to reference a DetailViewController and pass the data.

Answer 1

You can make a singleton implementation like:

static SingletonClass *_sharedClass = nil;
@implementation SingletonClass

@synthesize sharedVar;

+ (SingletonClass*)sharedClass
{
    if (_sharedClass == nil) {
        _sharedClass = [[SingletonClass alloc] init];
    }
    return _sharedClass;
}

- (id)init
{
    if ((self = [super init])) {
        //init any class vars you need
    }
    return self;
}
@end

Then have sharedVar be a property of the class. From anywhere in the app, you can use:

[[SingletonClass sharedClass] sharedVar];

to access it.