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Code Issues 29 Pull requests Releases Activity

clean up and fix up jumping

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This commit is contained in:
Henry Hiles 2026-09-29 19:24:16 -04:00
commit 1e4aab08ad
Signed by: Henry-Hiles
SSH key fingerprint: SHA256:VKQUdS31Q90KvX7EkKMHMBpUspcmItAh86a+v7PGiIs
1 changed files with 41 additions and 64 deletions
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103
lib/helpers/hooks/chat_scroll.dart
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@ -1,5 +1,3 @@
import "dart:async";
import "package:fast_immutable_collections/fast_immutable_collections.dart";
import "package:flutter_hooks/flutter_hooks.dart";
import "package:hooks_riverpod/hooks_riverpod.dart";
@ -26,28 +24,20 @@ final class ChatScroll({
required ValueNotifier<int?> contextualEvent,
}) {
final anchorId = useState<int?>(null);
final atBottom = useState(true);
final pendingJump = useState<int?>(null);
final scrollController = useScrollController();
final centerKey = useMemoized(GlobalKey.new);
final itemKeys = useMemoized(() => <int, GlobalKey>{}, []);
GlobalKey keyFor(int eventRowId) =>
itemKeys.putIfAbsent(eventRowId, GlobalKey.new);
final scrollController = useScrollController();
final centerKey = useMemoized(GlobalKey.new);
final atBottom = useState(true);
final pendingAnchorTarget = useState<int?>(null);
final anchorMountedCompleter = useRef<Completer<BuildContext>?>(null);
useEffect(() {
if (anchorId.value == null) {
if (controllerData case AsyncData(:final value?)
when value.timeline.isNotEmpty) {
final hasContextualEvent = value.timeline.any(
(event) => event == contextualEvent.value,
);
anchorId.value = hasContextualEvent
anchorId.value = value.timeline.contains(contextualEvent.value)
? contextualEvent.value
: value.timeline.last;
}
@ -57,35 +47,34 @@ final class ChatScroll({
}, [controllerData, contextualEvent.value]);
useEffect(() {
final target = pendingAnchorTarget.value;
if (target == null) return null;
final rowId = pendingJump.value;
if (rowId == null || anchorId.value != rowId) return null;
pendingJump.value = null;
final found =
controllerData.value?.timeline.any((event) => event == target) ??
false;
WidgetsBinding.instance.addPostFrameCallback((_) async {
if (!scrollController.hasClients) return;
if (found || controllerData is AsyncError) {
if (found) {
anchorId.value = target;
final position = scrollController.position;
scrollController.jumpTo(
(-position.viewportDimension)
.clamp(position.minScrollExtent, position.maxScrollExtent)
.toDouble(),
);
await WidgetsBinding.instance.endOfFrame;
WidgetsBinding.instance.addPostFrameCallback((_) {
final context = keyFor(target).currentContext;
if (context != null && context.mounted) {
anchorMountedCompleter.value?.complete(context);
anchorMountedCompleter.value = null;
}
});
} else {
anchorMountedCompleter.value?.completeError(
StateError("Failed to load context for $target"),
final context = keyFor(rowId).currentContext;
if (context?.mounted == true) {
await Scrollable.ensureVisible(
context!,
alignment: 0.5,
duration: const .new(milliseconds: 700),
curve: Curves.easeInOut,
);
anchorMountedCompleter.value = null;
}
pendingAnchorTarget.value = null;
}
});
return null;
}, [controllerData, pendingAnchorTarget.value]);
}, [anchorId.value, pendingJump.value]);
final ({IList<int> history, IList<int> live}) split = useMemoized(() {
final items = controllerData.value?.timeline;
@ -97,9 +86,7 @@ final class ChatScroll({
final anchorIndex = items.indexOf(anchor);
if (anchorIndex == -1) {
return (history: const .empty(), live: items);
}
if (anchorIndex == -1) return (history: const .empty(), live: items);
return (
history: items.take(anchorIndex).toIList().reversed.toIList(),
@ -138,7 +125,6 @@ final class ChatScroll({
}
scrollController.addListener(checkPosition);
WidgetsBinding.instance.addPostFrameCallback((_) => checkPosition());
return () => scrollController.removeListener(checkPosition);
@ -158,35 +144,27 @@ final class ChatScroll({
centerKey: centerKey,
scrollController: scrollController,
atBottom: atBottom.value,
keyFor: keyFor,
jumpToEvent: (int rowId) async {
if (!scrollController.hasClients) return;
final existing = keyFor(rowId).currentContext;
if (existing != null && existing.mounted) {
// Already mounted, just scroll
await Scrollable.ensureVisible(
existing,
alignment: 0.5,
duration: const .new(milliseconds: 700),
curve: Curves.easeInOut,
);
} else {
final completer = Completer<BuildContext>();
anchorMountedCompleter.value = completer;
pendingAnchorTarget.value = rowId;
contextualEvent.value = rowId;
final context = await completer.future;
if (!context.mounted) return;
await Scrollable.ensureVisible(context, alignment: 10);
if (!context.mounted) return;
final context = keyFor(rowId).currentContext;
if (context != null) {
await Scrollable.ensureVisible(
context,
alignment: 0.5,
duration: const .new(milliseconds: 700),
curve: Curves.easeOutCirc,
curve: Curves.easeInOut,
);
return;
}
pendingJump.value = rowId;
if (controllerData.value?.timeline.contains(rowId) ?? false) {
anchorId.value = rowId;
} else {
anchorId.value = null;
contextualEvent.value = rowId;
}
},
jumpToBottom: () async {
@ -203,7 +181,6 @@ final class ChatScroll({
curve: Curves.easeInOut,
);
},
keyFor: keyFor,
);
}
}