addValueIdsListener

The addValueIdsListener method registers a listener function with the Store that will be called whenever the Value Ids in a Store change.

addValueIdsListener(
  listener: ValueIdsListener<Store>,
  mutator?: boolean,
): string

The provided listener is a ValueIdsListener function, and will be called with a reference to the Store.

By default, such a listener is only called when a Value is added or removed. To listen to all changes in the Values, use the addValuesListener method.

Use the optional mutator parameter to indicate that there is code in the listener that will mutate Store data. If set to false (or omitted), such mutations will be silently ignored. All relevant mutator listeners (with this flag set to true) are called before any non-mutator listeners (since the latter may become relevant due to changes made in the former). The changes made by mutator listeners do not fire other mutating listeners, though they will fire non-mutator listeners.

import {createStore} from 'tinybase';

const store = createStore().setValues({open: true});
const listenerId = store.addValueIdsListener((store) => {
  console.log('Value Ids changed');
  console.log(store.getValueIds());
});

store.setValue('employees', 3);
// -> 'Value Ids changed'
// -> ['open', 'employees']

store.delListener(listenerId);

import {createStore} from 'tinybase';

const store = createStore().setValues({open: true});
const listenerId = store.addValueIdsListener(
  (store) => store.setValue('updated', true),
  true, // mutator
);

store.setValue('employees', 3);
console.log(store.getValues());
// -> {open: true, employees: 3, updated: true}

store.delListener(listenerId);