Question

I am presenting a modal view controller to show detailed information. I have it set up so that any change to the information in the modal view controller will change the information in its parent view controller.

The information is changed, but I cannot manage to reload the gridView data when the modal view controller is dismissed. Right now I have the action to dismiss the modal inside the modal view controller. Everything works good, I just can’t reload the data for the gridView from the modal view controller.

I read somewhere that one of the options is to create a delegate that will be able to dismiss the modal view controller from the parent view controller, I just can’t seem to find examples or nice tutorials on how to go by doing this. The truth is that I know how to use the delegates, but not quite sure on how to properly implement one.

Can anyone please point me in the right direction here? Maybe someone has a better option. I am open to any suggestions.

Answer 1

If I understand clearly, you want to reload the grid contained in your parent view controller when you dismiss the modal view controller. If so, here how:

Declare a protocol in your ModalViewController by doing something like

@protocol MyViewControllerDelegate;

@interface MyViewController : UIViewController {

    id<MyViewControllerDelegate>delegate;
    // Your stuff
}

@property (nonatomic, assign) id<MyViewControllerDelegate>delegate;

@end

@protocol MyViewControllerDelegate <NSObject>

-(void)viewControllerWasDismissedOrAnyOtherNameYoudLike;

@end

And in your .m file, just @synthesize delegate.

Just when you call dismissModalViewController:animated:, also call [delegate viewControllerWasDismissedOrAnyOtherNameYoudLike].

In your view controller with the grid view, import the header file of your modalviewcontroller, conform to the protocol

@interface MyGridViewController : UIViewController <MyViewControllerDelegate>

When you init the Modalview controller, set the delegate to self, and implement the viewControllerWasDismissedOrAnyOtherNameYoudLike method.
Voilà!