repl_view #

Generic REPL-style scroll view for Flutter.

Part of flutter_scroll_kit — composable Flutter scroll primitives.

Input lines pin as sticky section headers; response lines scroll as leaves within each section. Repeated identical responses coalesce with a count badge (e.g. "ok x47" instead of 47 identical lines) when the consumer's data source supplies a pre-coalesced entry with count > 1.

Built on sticky_hierarchical_scroll.

Usage #

class MyEntry implements ConsoleEntry {
  @override
  final String value;
  @override
  final bool isInput;
  @override
  final String coalescingKey;
  @override
  final int count;
  @override
  final Object identity;

  MyEntry({
    required this.value,
    required this.isInput,
    required this.coalescingKey,
    required this.identity,
    this.count = 1,
  });
}

ReplView<MyEntry>(
  entries: entries,
  itemExtent: 16.0,
  entryBuilder: (context, entry) {
    return Row(
      children: [
        if (entry.count > 1)
          Container(
            padding: const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
            margin: const EdgeInsets.only(right: 6),
            decoration: BoxDecoration(
              color: Theme.of(context).colorScheme.surfaceContainer,
              borderRadius: const BorderRadius.all(Radius.circular(7)),
            ),
            child: Text('${entry.count}'),
          ),
        Expanded(child: Text(entry.value, overflow: TextOverflow.ellipsis)),
      ],
    );
  },
);

Interface #

Features #

• Sticky input headers — input entries pin at the top of their response scope (VS Code terminal style).
• Coalescing display — consumer-supplied count > 1 on an entry lets the entryBuilder render a count badge, keeping the scrollback compact.
• Identity-anchored viewport — two observable states:
  • Stuck to bottom (default): new entries, coalescing updates, parent rebuilds, and tab detach/reattach all resettle to the bottom.
  • Floating: when the user drags away from the bottom, the viewport pins to a specific entry by identity plus a pixel offset within it. Tail appends and coalescing leave the pinned content unchanged. When the anchor entry is trimmed from the consumer's scrollback, the view snaps back to the bottom and returns to stuck.
• Trailing items — optional prompt line, separators, or status text scroll with the content rather than pinning as a footer.

Parameters #

Design #

Coalescing happens upstream in the consumer's data source. The widget reads the supplied count and hands the entry to entryBuilder — it does not dedupe entries. This keeps the package agnostic to the consumer's equivalence relation (exact string match, regex canonicalisation, session-scoped key, etc.).

Input entries render as level-0 sticky sections; responses render as level-1 leaves. Depth is fixed at 2 — the REPL model has one level of nesting (input -> its responses), unlike the general sticky_hierarchical_scroll which supports arbitrary depth.