Track Held Keys and Modifier State in Vue

These composables report which keys the user is holding right now. They're optional helpers for your UI: show which modifiers are down, or change a button while Shift is held. You don't need them to register hotkeys. To show a button's shortcut while the user holds its modifiers, see Hotkey Hints.

Each composable returns a ref, which templates unwrap for you.

Show which keys are held#

useHeldKeys returns the held keys in the order they were pressed, such as ['Control', 'Shift', 'A']:

<script setup lang="ts">
import { useHeldKeys } from '@tanstack/vue-hotkeys'

const heldKeys = useHeldKeys()
</script>

<template>
  <div>
    {{ heldKeys.length > 0 ? `Held: ${heldKeys.join(' + ')}` : 'No keys held' }}
  </div>
</template>

Check whether a key is held#

useKeyHold returns whether one key is held. It updates only when that key is pressed or released, and accepts a ref or getter for a key that changes:

<script setup lang="ts">
import { useKeyHold } from '@tanstack/vue-hotkeys'

const props = defineProps<{ file: File }>()
const isShiftHeld = useKeyHold('Shift')
</script>

<template>
  <div>
    <span>{{ file.name }}</span>
    <button v-if="isShiftHeld" @click="permanentlyDelete(file)">Delete permanently</button>
    <button v-else @click="moveToTrash(file)">Move to trash</button>
  </div>
</template>

Tell left and right modifiers apart#

useHeldKeyCodes maps each held key to the physical key that's down, from event.code:

<script setup lang="ts">
import { useHeldKeyCodes } from '@tanstack/vue-hotkeys'

const heldCodes = useHeldKeyCodes() // e.g. { Shift: 'ShiftLeft', Control: 'ControlRight' }
</script>

<template>
  <p v-if="heldCodes.Shift === 'ShiftRight'">Right Shift is held</p>
</template>

Read held keys in an event handler#

To read the held keys in an event handler without tracking them, use the shared tracker from getKeyStateTracker:

<script setup lang="ts">
import { getKeyStateTracker } from '@tanstack/vue-hotkeys'

const tracker = getKeyStateTracker()

function onClick() {
  if (tracker.isKeyHeld('Space')) startPanning()
  else if (tracker.isAnyKeyHeld(['Shift', 'Control'])) addToSelection()
  else select()
}
</script>

<template>
  <canvas @click="onClick" />
</template>

The tracker starts listening the first time you get it, so get it in setup, before the user presses the keys you care about. Call its methods inside the handler to read the state at that moment. It also has getHeldKeys() and areAllKeysHeld(keys). Don't destroy the tracker when a component unmounts, because every composable shares it.

For a mouse or wheel event, event.ctrlKey, shiftKey, altKey, and metaKey already report the modifiers. Browsers also set ctrlKey for a trackpad pinch, so it doesn't always mean Control is held.

Held keys clear when the window loses focus, so a key released after switching apps doesn't stay held. Held keys reset when the window loses focus covers the cases the tracker handles.

The useHeldKeys example shows held keys and their codes, and the useKeyHold example shows modifier indicators.