Storyboard viewcontroller circular dependency issue

[foulkesjohn]

I am loading view controllers from TyphoonStoryboard and have a definition for the class which works fine, several properties are injected with no problems. However one of the properties is a view which itself has a delegate property which I want to be the view controller instance. When the view comes to set the delegate property it tries to create a new instance of the view controller instead of using the instance which has been created by the storyboard. How can I make the delegate property use the current instance of the view controller? My definitions look something like this:

- (id)viewController
{
  return [TyphoonDefinition withClass:[MyViewController class] configuration:^(TyphoonDefinition *definition) {
    [definition injectProperty:@selector(view) with:[self myView]];
  }];
}

- (id)myView
{
  return [TyphoonDefinition withClass:[MyView class] configuration:^(TyphoonDefinition *definition) {
    [definition injectProperty:@selector(delegate) with:[self viewController]];
  }];
}

From what I can see the view controller can never be used a reference as it doesn't added a shared reference anywhere and Typhoon has no option but to instantiate a new one?

[alexgarbarev]

Yeah. That is problem, since viewController created by Storyboard and not owned by typhoon (which required to work with circular references)
I think there is not way to wire delegate to viewController with Typhoon. But you can try wire by InterfaceBuilder: mark your delegate property as IBOutlet and connect to controller.

[jasperblues]

We like to have use GH for bug tracking and general support on Stack Overflow. The advantage of StackOverflow is wider community involvement and therefore faster response time, and also its very well indexed by Google for future users. So, I hope you don't but I've copied your question here:

http://stackoverflow.com/questions/27986510/typhoon-wire-circular-dependency-in-storyboard-created-view-controller/27986663#27986663

[jasperblues]

If we do end up discovering a bug a feature request we can always reopen a new issue. Thanks for choosing Typhoon.

[foulkesjohn]

My initial thoughts are that it should be straight forward to keep references to any storyboard created through TyphoonStoryboard and therefore easy to hook up them up as dependencies?

[jasperblues]

There's a TyphoonStack used for resolving circular dependencies along with an object-graph (default) scope pool. Perhaps we can push on this stick prior to instructing Typhoon to inject deps on the instance.

[alexgarbarev]

@jasperblues Agree. We can leave this as feature request and do that special case in order of TyphoonStoryboard.. (i.e. making TyphoonStoryboard more integrated into Typhoon-core)

[jasperblues]

@foulkesjohn I made a change to that I think should work, but can't do unit tests at the moment. Can you try update to:

pod 'Typhoon', :head

And let me know how it goes?

[foulkesjohn]

Doesn't seem have made a difference, not sure where to look to try and debug it either. Where should I be looking to try track down whats wrong?

[jasperblues]

Oops. I only took you part of the way there. Can you try again?

Where should I be looking to try track down whats wrong?

Circular dependencies can be tricky because there's lots of recursion involved. It relies on TyphoonCallStack, scopes and the id<TyphoonComponentPool>. See TyphoonComponentFactory+InstanceBuilder . . in the case of a pre-obtained instance, the stack and shared pools weren't being intitialized pre to hooking into the property injector, hence circular deps wouldn't work.

[jasperblues]

One more change, and added the following test case, which passes:

- (void)test_first_resolves_circular_dependencies {
    StoryboardFirstlViewController *controller = [storyboard instantiateViewControllerWithIdentifier:@"first"];
    StoryboardControllerDependency *dependency = controller.dependency;
    StoryboardFirstlViewController *circular = dependency.circularDependencyBackToViewController;

    XCTAssertTrue(controller == circular);
}

Thanks for your patience.

[foulkesjohn]

That seems to have worked, thanks for looking at it so quickly

[jasperblues]

We'll push this out as a minor version then, so you don't have to pod from :head . . pushing now.

[jasperblues]

Pushed Typhoon 2.3.4 to CocoaPods master repo.