BackHandler typedef

BackHandler = Future<bool> Function()

Host-supplied back-navigation hook.

In practice this is _EmbedWidgetState._handleBackRequest, which is itself the full Android-parity ladder — host hook → nearest Navigator (maybePop, so PopScope is honoured) → system-back sweep of every reachable navigator deepest-first. The runner runs the nav-stack tab-restore rung before this executor, mirroring Android's four-rung core/intelligence/exec/BackExecutor.kt.

Implementation

typedef BackHandler = Future<bool> Function();