Question

I have 3 viewcontrollers that are switched by a swipe gesture (like a carrousel). The data is dynamic, so is there anyway to store the viewcontroller, so when I swipe back to it, it doesn’t have to reload the data?

Answer 1

You dont need to store, just dont release them
Another way to ensure that you dont release them

In your app delegate
.h file

Add a property

@interface AppDelegate : UIResponder <UIApplicationDelegate>
{
    NSMutableArray *viewControllers;
}
@property (retain, nonatomic) NSMutableArray *viewControllers;

In the .m File synthesize it and allocated it in didFinishLaunchingWithOptions

self.viewControllers = [[NSMutableArray alloc] init];

Now add all your view controllers to this mutable array

AppDelegate *delegate = [UIApplication sharedApplication].delegate;
[delegate.viewControllers addObject:myViewController];

And now when you want to use any of the view controllers you have. you could access it from

AppDelegate *delegate = [UIApplication sharedApplication].delegate;
myViewContoller = [delegate.viewControllers objectAtIndex:0];