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FilterStore.watch() method

Subscribes to changes of a specific filter state property.

Watch a single property for changes. More efficient than watching the entire state when you only care about specific properties.

Signature:

watch<K extends keyof FilterStates>(key: K, callback: (value: FilterStates[K]) => void): () => void;

Parameters

Returns:

() => void

Unsubscribe function to stop watching this property

Example 1

Watch a specific property:

const unsubscribe = filterStore.watch('latestRequestKey', (key) => {
  console.log('Latest request key changed to:', key);
});

Example 2

Extend to add custom watcher behavior:

window.boostWidgetIntegration.extend('FilterStore', (FilterStore) => {
  return class CustomFilterStore extends FilterStore {
    watch(keyOrCallback, callback) {
      const unsubscribe = super.watch(keyOrCallback, callback);
      console.log('New watcher registered');
      return () => {
        console.log('Watcher removed');
        unsubscribe();
      };
    }
  };
});