And their restitutions doesn't combine, the software just used the higher one? restitution is how much energy the physics body loses when it bounces off another object. So it seems logical to have 0.8 as a result. You should try: ball.restitution = 0.4 // <<-- Swapped with block block.restitution = 0.8 My guess would be restitution used by physics engine should be 0.4

buggy forum. I have to repost to get the previous post visible !

if foods were class, would that make a difference? Yes, because in this case you pass a reference. So when you modify item.isSelected.toggle() this applies to the pointed reference, not to a copy of it as is the case with struct.

Check the cells you dequeue are the cells defined in the CollectionView.     let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CollectionViewCell", for: indexPath) as! CollectionViewCell Check in particular as! CollectionViewCell

I should, but some who tried have visibly got serious problems: https://developer.apple.com/forums/thread/682815. You'd better double check by contacting Apple Support (Contact Us link at the bottom of this page).

Is this possible without enrolling in the ADP as an individual? Collaboration is possible with a common Git repository. Being declared as team member is necessary when you want to be able to publish on the appstore by several members. So you will have to do it once your company is created. Or if you prefer, share the same account on several Mac.

There is no problem running directly, but there is a problem running after Archive Could you explain exactly the sequence of what you do and when it crashes ?

Do I need to change the code handling the placement of the UI elements using fractions of the screen width and height instead of fixed whole numbers?  I would advise not to do that, that will give a poor result and be pretty complex to manage. Or do I add a line to the GameViewController that looks for which type of device is being used and then throws to a different set of files with values specific to that device? I would not do this either. I see 2 main options: Use constraints to position elements relatively to the whole view (or safe area). It will be OK on a larger than iPhone 11, but on a small screen, you will have problem to fit them all. You will probably manage on a 5.5" screen, but will be hard on a 4.7 or worse 4" screen. Embed the whole scene in a UIView withy a fixed size equal ti size of the iPhone11 screen. Set constraints relatively to this view Then embed this View into a Scrolling view. Set the constraints of the scrollView to the safe area In any case, clearly warn on the app description that it best works on screens larger than (iPhone 11 screen) Result: In iPhone 11, you will see no change. on larger screens, you will have some unused space, but no scrolling on smaller screens, user will have to scroll ; may be a bit tricky for a game.

Could you show a screenshot ? Here is what I get in an app:

Please how the present extensions you have in the 12.5 project. When you open the existing project, do you get warnings (in Issues Navigator on the left pane) advising to update to new settings ? If so, do it. You could also do a Clean Build Folder. Finally, search everywhere in code for the button.

I'm sure the tag I selected doesn't have anything to do with what I am asking, You're right, but that's not a major problem. In the future, just start typing UIK in the textField for selecting tag. Then you can select UIKit… I am in the process of building Loop in Xcode and cannot understand how to move around in there What Loop do you mean ? Is it a question of using Xcode ? To loop between what in Xcode ? Or a question how to program something to select fields in your app ? If so, please show the code you try (even if it does not work) Please clarify.

Is it a compiler error or a compiler warning ?

I cannot understand your question. What does not work ? What would you expect ? But the output image obtained is slightly different for iOS 15 when compared with iOS 14. Different in what ? Colors ? Size ? orientation ?

Have you checked you connected correctly textFields in storyboard to their IBOutlet ? The code you posted if of little use. Could you post the full code of the class where you have the textFields IBOutlets ?

Did you ask the app developer ? The problem may be on their side. Please note also when you ask a question: it is not enough to say "it doesn't work" you have to tell which version of OS, which version of app… you have also to explain the problem itself: cannot download ? cannot launch ? crash at launch ? select the appropriate tag. I don't think your problem is related to WWDC21-10002 It seems others had similar problem in the past : https://developer.apple.com/forums/thread/122771