Expose boolean of whether an item is currently visible in the grid

[Sindre Sorhus]

I have a large grid of NSImageView's that play animated GIFs. This is very resource intensive, so I would like to pause playing the GIF animation for items that are outside the viewport. It would be useful if Grid could somehow expose this information.

[Sindre Sorhus]

It would also be useful with a method that runs a callback when an element enters/exits the viewport, since .onAppear() triggers for all grid elements at load time and not when they enter the viewport. Maybe called .onVisibilityChange(isVisible:).

[Victor Mihaita]

@ay42 I try to paginate my API calls using this logic and is impossible because I cannot know when the last item in my dataSource is displayed. I think this is an important fix as well as #81
Do you have an ETA for this?

[Alexander Young]

@victormihaita most likely this feature will not be implemented. Just like HStack and VStack, Grid is a lower level layout element. I imagine this can be done with the ViewModifier on the presented views directly but not as a part of this project.

[Alexander Young]

@victormihaita I'm looking for a way to fix #81, do you know how to do it?

[Victor Mihaita]

In this code, when calling onAppear, I expect that it should be called only for the elements visible on the screen, but instead is called for all the elements in the grid. is that correct? This causes also the issue #81 in my case.

Grid(viewModel.dataSource, id: \.id) {
    CardView($0).onAppear {
        //Do something
    }
}