History HistoryBoundary

HistoryBoundary

The hairline where full messages begin, below the compacted history: an arrow, "Full messages from here" and the number of the first message shown in full.

import 'package:agent_kit/agent_kit.dart';

Demo

Boundary in the 1600 px scene: a hairline on each side of "Full messages from here", then "message 132". The gallery passes messageNumber: 132.

Parameters

Parameter	Type	Notes
messageNumber	int (required)	One-based number of the first message shown in full. It is written after the text, unless the width is compact.

Theme roles

thread (the two hairlines), ink (the "Full messages from here" text, weight 600), faint (the message number), colors.iconSecondary (the arrow), typeScale.uiSmall.

Size classes

The widget reads sizeClassOf(context).isCompact. Compact widths leave out "message N"; the text and both hairlines stay.

Accessibility

• The row is a Semantics container labelled "Full messages start here, from message N". Its visible children are excluded from semantics (ExcludeSemantics), so the label is read in place of the visible text.
• No keyboard or tap handling.
• No reduced-motion handling in this file.

Gallery and tests

• Gallery scene: History (GalleryScene.history, HistoryScene). It is the boundary entry of the scene's timeline, with messageNumber: 132, and it is the scene's initial anchor.
• Golden: apps/gallery/test/component_shots_test.dart writes history_boundary (index 0), _light.png and _dark.png. The whole scene is in h_history_1600_<theme>.png and h_history_390_<theme>.png.
• Other tests, packages/agent_kit/test/history/history_test.dart:
  • "names the first full message"
  • "leaves the number out when compact"

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Generated from docs/components/history/HistoryBoundary.md. Edit the file there; changes made on the wiki are overwritten.