A child view controller framework that makes setting up your parent controllers as easy as pie.

Hello I'm trying to give a little help regarding support of Swift Package Manager as I need it in one of my project :) This is a very simple implementation I just did and allowed me to use Family with SPM recently. I'm not sure if this is good enough but I think it is a good base to start with if it helps.

Changes

• Create target for shared code between macOS and mobile platforms (iOS & tvOS) named Family-Shared. This target is used by both macOS and mobile target.
• Family-mobile encapsulate both tvOS and iOS frameworks.

Hello and thanks for this library :)

We're trying to take advantage of child view controllers to split a view controller that is now really too complex. Here is how we want to organize it after refactoring (at the moment this is one UITableViewController subclass):

1. One view controller for the header
2. One view controller for our list of items that are linked to core data using an NSFetchedResultsController
3. A fixed view controller for a toolbar allowing to enter text and create content

I've just started to play with your library and I encountered a problem : our header has a dynamic height, which is set automatically with auto layout constraints. I've succeed to set fixed height for this container using the height parameter of addChild but with only auto layout constraints I couldn't. Also I encountered a case where I could scroll in the tableview and the main scroll view wasn't scrolling..

So I would like to know if this is supported to have height set using auto layout? Regarding https://github.com/zenangst/Family/issues/73 I have the feeling it's not.

Regarding your experience in child view controller, is it a good pattern to split this controller in three view controllers in that way? Maybe it's just easier to use the table view header to add the header controller?

I've included a sample project to quickly show the problem I'm having. Test family.zip

Thanks for your help!

The view hierarchy is FamilyViewController --UICollectionView inside a UIViewController --UICollectionView inside a UIViewController

They are added using addChild(viewController, view: { $0.collectionView })

Each collectionView has 50 items retrieved from network with content size over the screen height. The result is that the collectionView does not show all the items when scrolling down. The demo project is here https://github.com/superk589/FamilyDemo What's wrong in my implementation?

Hello,

I have a new issue related to the last fix made for UICollectionViewController (viewWillAppear not called). The did select item method isn't triggered in my UICollectionViewController subclass anymore after update to the last version of Family. Also the navigation bar doesn't update its large title to small title when scrolling (it works fine with only a table view).

Steps to reproduce:

1. Create a FamilyViewController containing a view controller subclassing UICollectionViewController
2. Present the controller
3. Override collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) in your UICollectionViewController subclass

Whats happens:

• The collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) method isn't called on the UICollectionViewController subclass.
• The navigation bar doesn't update its large title while scrolling

What should happens:

• collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) should be called correctly.
• The navigation bar update its large title while scrolling

Sample: Test family collection view 2.zip

Is it possible to use Family to create a card-like interface, similar to Snapchat or Duolingo with multiple rounded cards that scroll infinetely?

So far I was able to achieve a very similar effect, but with some flaws using this code:

  func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    let family = FamilyViewController()
    family.view.backgroundColor = .white
    let vc1 = TableViewController1()
    let vc2 = TableViewController2()

    family.addChild(vc1)
    family.addChild(vc2)
    window = UIWindow(frame: UIScreen.main.bounds)
    window?.rootViewController = family
    window?.makeKeyAndVisible()

    return true
  }

The result looks like this:

So, the problem is really with the outer corners which should not be visible if there is some content further down (or up) the table.

What would be ideal is to add some padding where the views could extend before being recycled.

I.e. currently the tableviews are limited by the FamilyController's alignment rect, or at least, respects the top and bottom safe area insets. Because of that, the layout looks weird on the X-series phones.

Having some parameter (i.e. margins to extend) would give an option to both achieve the card-like looks and fix the x-series bug.

Video Description

This new issue only occurs on real devices. (The device above is iOS 12.4, iPhone X) When a collection view with more than one screen items followed by a new collection view with fewer items, the first collection view will be jumpy. Use demo code here(the newest commit): https://github.com/superk589/FamilyDemo

Issue

Hello,

First, thanks for your framework we have complex ViewController in our app and this is really useful for us!

I have an issue when I remove a view from the parent view controller. purgeRemovedViews() & scrollView.purgeWrapperViews() are not called so obviously the height is not correctly resize and a blank space is still visible.

If you want to test the issue, please find this sample.

Test no resize height.zip

Fix

The fix is pretty simple because all methods already exists. I just create a removeChild function (as we have for the addChild) to call this private methods purgeRemovedViews() & scrollView.purgeWrapperViews().

I found this bug when embedding a UITextView inside a UITableViewCell, then in a FamilyViewController. UISelectionGrabberDot is a private type of UIKit, it represents the two pins on the two sides of the selected range.

This view is wrapped by FamilyWrapperView. And it causes some strange behavior such as an incorrect frame of the dot's first ancestor scroll view subclass, the UITextView.

Hi, this is not an issue but more of a question of how to use your library. I have a view controller built in storyboard and it has multiple views that require their own controller. However, because I don't know how to set child view controller properly, I have one massive view controller managing three different views. I find this library very useful in terms of separating three views into separate view controllers and having a parent controller.

1. Can I have FamilyViewController as subclass of my parent controller that is built in storyboard?
2. For the views that I have setup in storyboard using constraints, is it possible for me to have each view have child view controller like, view1 = viewController1.view when I do add addChild(viewController1)?
3. How does the memory allocation work, do all child and parent view controllers get deallocated as soon as the navigation controller gets dismissed since they are part of navigation controller stack?

Hello,

I have a new issue, this time when using an UICollectionViewController as child controller :)

Steps to reproduce:

1. Create a FamilyViewController containing a view controller subclassing UICollectionViewController
2. Present the controller

Whats happens: The viewWillAppear method isn't called on the UICollectionViewController subclass.

What should happens: viewWillAppear should be called correctly.

I've found a workaround by creating an UIViewController containing an UICollectionView, then it's working correctly.

Sample: Test family collection view.zip

I can hardly say this is a reasonable use case. But this is what I am dealing with. There is a collection view, like an excel table, which can scroll both vertically and horizontally, is inside a FamilyViewController. But with isDirectionalLockEnabled, it can only scroll at one direction at one time.

Because FamilyScrollView has code lines below:

  func configureScrollView(_ scrollView: UIScrollView) {
    #if os(iOS)
    scrollView.scrollsToTop = false
    if let collectionView = scrollView as? UICollectionView,
      (collectionView.collectionViewLayout as? UICollectionViewFlowLayout)?.scrollDirection == .horizontal {
      scrollView.isScrollEnabled = true
    } else {
      scrollView.isScrollEnabled = false
    }
    #else
    for scrollView in subviewsInLayoutOrder {
      scrollView.isScrollEnabled = scrollViewIsHorizontal(scrollView)
    }
    #endif
  }

The "excel" collection view always has it's scrollView.isScrollEnabled on. It sometimes freezes the whole FamilyViewController vertically, when it fills the whole screen and can only scroll horizontally. The gesture can not pass to the container scroll view below.

Hello,

We're having some weird issues when trying to add a UIRefreshControl on top of FamilyViewController. When pulling everything if fine. But whenever we're refreshing, the refresh control just disappears or is having a lot of UI issues.

I can reproduce this in the demo app by enabling large title and setting up scrollView.refreshControl = UIRefreshControl()

Note that it's the same if we're trying to use directly FamilyScrollView.

Do you have any idea what could cause this?

Thank you so much :)

Instead of having a bundled Xcode project, I'd like to propose using XcodeGen to generate the project-based of a .yml file. This would reduce the occasional merge conflicts that can occur when multiple people are making PR's at the same time. Also, it would clean up PR's by not including Xcode project changes as they are invalid with XcodeGen in place.

For more information about XcogeGen, check out their README

• https://github.com/yonaskolb/XcodeGen

The README could use some updating to ensure that we both explain the underlying technical aspects of the framework, how the algorithm works, and some best practice information on how to best adapt the framework into your apps.

Some example images of what could be built would be a big bonus here.

Family does one thing and it does it pretty great. It is to encapsulate scroll views (and other views) into one scrollable feed meanwhile ensuring that dequeuing stays intact for things like collection views and table views and that performance is still top-notch. This is normally kinda hard to achieve in UIKit, hence the framework's inception.

The way forward, now that we are slowly transitioning into the world of SwiftUI, it would be interesting to see if this framework could be adapted to support the same kind of functionality in that landscape. SwiftUI does support multiple vertical stacks inside of a scroll view, but not with things like List which is harder to get working when they should be self-sizing.

I propose that we do some experimentation here to see if there is a future for Family inside SwiftUI-land.

We should consider rewriting the test suites for the different targets to ensure that we have all the most important parts of the framework covered. Now, tvOS is lagging a bit behind the other platforms.