Adds a change listener. It will be called any time an action is
dispatched, and some part of the state tree may potentially have changed.
You may then call getState() to read the current state tree inside the
callback.
You may call dispatch() from a change listener, with the following
caveats:
The subscriptions are snapshotted just before every dispatch() call.
If you subscribe or unsubscribe while the listeners are being invoked,
this will not have any effect on the dispatch() that is currently in
progress. However, the next dispatch() call, whether nested or not,
will use a more recent snapshot of the subscription list.
The listener should not expect to see all states changes, as the state
might have been updated multiple times during a nested dispatch() before
the listener is called. It is, however, guaranteed that all subscribers
registered before the dispatch() started will be called with the latest
state by the time it exits.
Adds a change listener. It will be called any time an action is dispatched, and some part of the state tree may potentially have changed. You may then call
getState()to read the current state tree inside the callback.You may call
dispatch()from a change listener, with the following caveats:The subscriptions are snapshotted just before every
dispatch()call. If you subscribe or unsubscribe while the listeners are being invoked, this will not have any effect on thedispatch()that is currently in progress. However, the nextdispatch()call, whether nested or not, will use a more recent snapshot of the subscription list.The listener should not expect to see all states changes, as the state might have been updated multiple times during a nested
dispatch()before the listener is called. It is, however, guaranteed that all subscribers registered before thedispatch()started will be called with the latest state by the time it exits.