useThrottledState

function useThrottledState<TValue, TSelected>(
   value,
   options,
   selector?): [TValue, Dispatch<StateUpdater<TValue>>, PreactThrottler<Dispatch<StateUpdater<TValue>>, TSelected>];

Defined in: throttler/useThrottledState.ts:91

A Preact hook that creates a throttled state value that updates at most once within a specified time window. This hook combines Preact's useState with throttling functionality to provide controlled state updates.

Throttling ensures state updates occur at a controlled rate regardless of how frequently the setter is called. This is useful for rate-limiting expensive re-renders or operations that depend on rapidly changing state.

The hook returns a tuple containing:

• The throttled state value
• A throttled setter function that respects the configured wait time
• The throttler instance for additional control

For more direct control over throttling without state management, consider using the lower-level useThrottler hook instead.

State Management and Selector

The hook uses TanStack Store for reactive state management via the underlying throttler instance. The selector parameter allows you to specify which throttler state changes will trigger a re-render, optimizing performance by preventing unnecessary re-renders when irrelevant state changes occur.

By default, there will be no reactive state subscriptions and you must opt-in to state tracking by providing a selector function. This prevents unnecessary re-renders and gives you full control over when your component updates. Only when you provide a selector will the component re-render when the selected state values change.

Available throttler state properties:

• executionCount: Number of function executions that have been completed
• lastArgs: The arguments from the most recent call to maybeExecute
• lastExecutionTime: Timestamp of the last function execution in milliseconds
• nextExecutionTime: Timestamp when the next execution can occur in milliseconds
• isPending: Whether the throttler is waiting for the timeout to trigger execution
• status: Current execution status ('disabled' | 'idle' | 'pending')

Type Parameters

TValue

TValue

TSelected

TSelected = ThrottlerState<Dispatch<StateUpdater<TValue>>>

Parameters

value

TValue

options

PreactThrottlerOptions<Dispatch<StateUpdater<TValue>>, TSelected>

selector?

(state) => TSelected

Returns

[TValue, Dispatch<StateUpdater<TValue>>, PreactThrottler<Dispatch<StateUpdater<TValue>>, TSelected>]

Example

// Default behavior - no reactive state subscriptions
const [value, setValue, throttler] = useThrottledState(0, { wait: 1000 });

// Opt-in to re-render when execution count changes (optimized for tracking executions)
const [value, setValue, throttler] = useThrottledState(
  0,
  { wait: 1000 },
  (state) => ({ executionCount: state.executionCount })
);

// Opt-in to re-render when throttling state changes (optimized for loading indicators)
const [value, setValue, throttler] = useThrottledState(
  0,
  { wait: 1000 },
  (state) => ({
    isPending: state.isPending,
    status: state.status
  })
);

// Opt-in to re-render when timing information changes (optimized for timing displays)
const [value, setValue, throttler] = useThrottledState(
  0,
  { wait: 1000 },
  (state) => ({
    lastExecutionTime: state.lastExecutionTime,
    nextExecutionTime: state.nextExecutionTime
  })
);

// With custom leading/trailing behavior
const [value, setValue] = useThrottledState(0, {
  wait: 1000,
  leading: true,   // Update immediately on first change
  trailing: false  // Skip trailing edge updates
});

// Access throttler methods if needed
const handleReset = () => {
  setValue(0);
  throttler.cancel(); // Cancel any pending updates
};

// Access the selected throttler state (will be empty object {} unless selector provided)
const { executionCount, isPending } = throttler.state;