Make a session time scrolling sticky

[ryu38]

Issue

• close Sticky time scroll in session list #493

Overview (Required)

• Update a scrolling behavior in session list to stick a session time at the top of the list until replaced by a different one.

Links

• Nothing

Screenshot

Before

session_time_scroll.webm

After

sticky_scroll.webm

[takahirom]

Thanks for your great effort!
Probably this cause performance problem.
I think it is tough. But I came up with two approaches to solve this problem.

1. Use draw behind
   In this way, you can skip the composition and layout phase

        LazyColumn(
            modifier = Modifier.fillMaxSize().drawBehind {
                     ...
            }

2. Pass sessionsListListState and consume it in the function

This way, you can't skip the recompose, but you can narrow the recompose.

fun TimeLane(sessionsListListState, timetable) {
        val visibleItemsInfo = remember {
            derivedStateOf {
                sessionsListListState.layoutInfo.visibleItemsInfo
            }
        }
}

[ryu38]

I'm sorry for my late response.
Your advice helped me for fixing the code, thank you!
I adopted the second one in my code (I tried to solve this by using drawBehind but I can't ...).

[takahirom]

Thanks!

[github-actions]

There are differences in Compose previews:

[takahirom]

Can you run ./gradlew spotlessKotlinApply? 🙏

[takahirom]

Step 'ktlint' found problem in 'src/main/java/io/github/droidkaigi/confsched2022/feature/sessions/TimeLane.kt':
Error on line: 36, column: 1
rule: max-line-length
Exceeded max line length (100)
java.lang.AssertionError: Error on line: 36, column: 1

[github-actions]

There are differences in Compose previews:

[takahirom]

Please run ./gradlew composeLint and fix the issues🙇

[github-actions]

There are differences in Compose previews:

[takahirom]

Looks good! Thank you for your contribution!