`useSynchronizerStatusListener`

The useSynchronizerStatusListener hook registers a listener function with the Synchronizer that will be called when its status changes.

useSynchronizerStatusListener(
  listener: StatusListener<MergeableStoreOnly>,
  listenerDeps?: DependencyList,
  synchronizerOrSynchronizerId?: SynchronizerOrSynchronizerId,
): void

	Type	Description
`listener`	`StatusListener<MergeableStoreOnly>`	The function that will be called whenever the status of the `Synchronizer` changes.
`listenerDeps?`	`DependencyList`	An optional array of dependencies for the `listener` function, which, if any change, result in the re-registration of the listener. This parameter defaults to an empty array.
`synchronizerOrSynchronizerId?`	`SynchronizerOrSynchronizerId`	The `Synchronizer` to be accessed: omit for the default context `Synchronizer`, provide an `Id` for a named context `Synchronizer`, or provide an explicit reference.
returns	`void`	This has no return value.

This hook is useful for situations where a component needs to register its own specific listener to do more than simply tracking the value (which is more easily done with the useSynchronizerStatus hook).

Unlike the addStatusListener method, which returns a listener Id and requires you to remove it manually, the useSynchronizerStatusListener hook manages this lifecycle for you: when the listener changes (per its listenerDeps dependencies) or the component unmounts, the listener on the underlying Synchronizer will be deleted.

Example

This example uses the useSynchronizerStatusListener hook to create a listener that is scoped to a single component. When the component is unmounted, the listener is removed from the Synchronizer.

import {Provider, useSynchronizerStatusListener} from 'tinybase/ui-react';
import React from 'react';
import {createLocalSynchronizer} from 'tinybase/synchronizers/synchronizer-local';
import {createMergeableStore} from 'tinybase';
import {createRoot} from 'react-dom/client';

const App = ({synchronizer}) => (
  <Provider synchronizer={synchronizer}>
    <Pane />
  </Provider>
);
const Pane = () => {
  useSynchronizerStatusListener((synchronizer, status) =>
    console.log('Synchronizer status changed: ' + status),
  );
  return <span>App</span>;
};

const synchronizer = createLocalSynchronizer(createMergeableStore());
const app = document.createElement('div');
const root = createRoot(app);
root.render(<App synchronizer={synchronizer} />);

synchronizer.load();
// -> 'Synchronizer status changed: 1'
// ...
// -> 'Synchronizer status changed: 0'

synchronizer.save();
// -> 'Synchronizer status changed: 2'
// ...
// -> 'Synchronizer status changed: 0'

Since

v5.3.0