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I am new to compose and have written some Compose code using the Jetsnack sample code as a guide. One of the things that Jetsnack does not provide guidance for is how to dynamically add or remove items to scrollable lists. While I am trying to understand what to “remember” about a a list using videos, articles and Android documentation, a link to a sample app, code-lab or tutorial that illustrates adding or removing items to a list would be much appreciated.

No, but if the material that helps me understand how to add or remove list items also explains animation at the same time, that would be very cool.

In declarative UI frameworks you don't _add_ or _remove_ parts of UI. You just declare them or don't declare them.
For example consider this
```LazyColumn {
    item { Text("Item1") }
    item { Text("Item2") }
}```
Here you "remove" Item 2 by just not declaring it. This can be done for example with boolean flag.
```LazyColumn {
    item { Text("Item1") }
    
    if (item2Displayed) {
        item { Text("Item2") }
    }
}```
(This flag would have to be a `State` so the UI gets updated on change)

If your UI is backed by a list data structure, you either need to use an implementation of that data structure that is snapshot aware (eg `mutableStateListOf()`) or to store an immutable list in one (eg `mutableStateOf()`). In both those cases, when you add/remove from those lists, your compose ui should automatically update 

<@UE4JAH6M9> I do not think your answer is my case, which is more like `items { ... }`where one of the items is removed by tapping the element and selecting remove.

In that case Zachs answer is more helpful :slightly_smiling_face:

I was just describing the general idea of why you don't "just remove" a part of UI in declarative UI framework

Yes, Zach’s answer looks to be in the ballpark … now I just need to grok it.  Where “grok” means see it used in the wild. :-)

Maybe the `todoapp-lite` example may help:
<https://github.com/JetBrains/compose-jb/tree/master/examples/todoapp-lite/common/src/commonMain/kotlin/example/todoapp/lite/common>

Take a look at `RootStore`. It holds the list (wrapped in `RootState`) and provides methods to edit and remove items. Both are then used in `MainContent` (via `RootContent`).

<@U01UU8RM8KU> thanks for the suggestion. Checking it out now….

Just to wrap up this thread, my problem was not fully understanding that all elements of a list must be “remembered”, not just changes to the list.