mission_runner library

Classes

MissionCancelToken: External cancellation handle. reason is the wire failure_reason the terminal frame reports: cancelled for a backend cancel or a preemption, user_interrupted when a person touched the app (RN / Android interruptActive). The first reason wins.
MissionRunner: Orchestrates a MissionMessage end-to-end: walks steps in order, finds targets, dispatches to the right executor, verifies side effects, retries on failure, emits protocol events for both lifecycle (status) and outcome (verification).
MissionRunResult: Terminal outcome of a MissionRunner.run call.

raceCancel<T>(Future<T> work, CancelSignal signal, T onCancel(), {Duration poll = const Duration(milliseconds: 20)}) → Future<T>: Race work against signal (Android raceCancel): completes with work's value, or with onCancel's the moment signal fires — whichever is first. The abandoned work keeps running but is inert: every executor checkpoints the same signal before its next live-UI action. The signal is polled every poll (CancelSignal has no listener API).

HighlightCallback = void Function(UiNode target): Draws the highlight for a mission's highlight / scroll_and_highlight step on target (the re-found, settled node).
MissionFindCandidatesListener = void Function(FindCandidatesResponseMessage msg)
MissionInfoQueryListener = void Function(InfoQueryResponseMessage msg)
MissionPhaseListener = void Function(MissionPhaseMessage msg)
MissionStatusListener = void Function(MissionStatusMessage msg)
MissionVerificationListener = void Function(VerificationResultMessage msg)
RollbackCallback = Future<void> Function(MissionRunResult result)
ScrollerResolver = Scroller? Function(MissionStep step, UiSnapshot snapshot): Given a step (typically scroll_to / scroll_and_highlight) and the current snapshot, return the Scroller the step should drive — or null when no scrollable can be resolved.
SnapshotFactory = UiSnapshot? Function()
StepHighlightCallback = void Function(UiNode target, MissionStep step, String missionId): Richer highlight hook: also receives the step (for duration_ms) and the mission id (an internal hl_ mission draws through the standalone path). When set it replaces HighlightCallback for drawing.