ListenerCondition<T> typedef
ListenerCondition<T> =
bool Function(T previous, T current)
Signature for the listenWhen
function which takes the previous state
and the current state
and is responsible for returning a bool which
determines whether or not to call LidWidgetListener of LidListener
with the current state
Implementation
typedef ListenerCondition<T> = bool Function(T previous, T current);