pushBackHandler method

VoidCallback pushBackHandler(
  1. VoidCallback handler
)

Registers handler as the current target for Android's hardware back button — e.g. a drilled-in detail screen or a fullscreen viewer — instead of the panel or the host app underneath; call the returned callback once that view is gone.

Implementation

VoidCallback pushBackHandler(VoidCallback handler) {
  _backHandlers.add(handler);
  return () => _backHandlers.remove(handler);
}