onDismiss property

VoidCallback onDismiss

The handler for SemanticsAction.dismiss.

This is a request to dismiss the currently focused node.

TalkBack users on Android can trigger this action in the local context menu, and VoiceOver users on iOS can trigger this action with a standard gesture or menu option.

Implementation 

VoidCallback get onDismiss => _onDismiss;
void onDismiss= (VoidCallback value)

Implementation 

set onDismiss(VoidCallback value) {
  _addArgumentlessAction(SemanticsAction.dismiss, value);
  _onDismiss = value;
}