@implydata/tinykeys

A tiny (~400 B) & modern library for keybindings. See Demo

Install

npm install --save @implydata/tinykeys

Or for a CDN version, you can use it on unpkg.com

Usage

import { tinykeys } from "@implydata/tinykeys" // Or `window.tinykeys` using the CDN version

tinykeys(window, {
  "Shift+D": () => {
    alert("The 'Shift' and 'd' keys were pressed at the same time")
  },
  "y e e t": () => {
    alert("The keys 'y', 'e', 'e', and 't' were pressed in order")
  },
  "$mod+KeyD": event => {
    event.preventDefault()
    alert("Either 'Control+d' or 'Meta+d' were pressed")
  },
})

Alternatively, if you want to only create the keybinding handler, and register it as an event listener yourself:

import { createKeybindingsHandler } from "@implydata/tinykeys"

let handler = createKeybindingsHandler({
  "Shift+D": () => {
    alert("The 'Shift' and 'd' keys were pressed at the same time")
  },
  "y e e t": () => {
    alert("The keys 'y', 'e', 'e', and 't' were pressed in order")
  },
  "$mod+KeyD": event => {
    event.preventDefault()
    alert("Either 'Control+d' or 'Meta+d' were pressed")
  },
})

window.addEventListener("keydown", handler)

React Hooks Example

If you're using tinykeys within a component, you should also make use of the returned unsubscribe() function.

import { useEffect } from "react"
import { tinykeys } from "@implydata/tinykeys"

function useKeyboardShortcuts() {
  useEffect(() => {
    let unsubscribe = tinykeys(window, {
      // ...
    })
    return () => {
      unsubscribe()
    }
  })
}

Commonly used key's and code's

Keybindings will be matched against KeyboardEvent.key andKeyboardEvent.code which may have some names you don't expect.

Windows	macOS	key	code
N/A	Command / ⌘	Meta	MetaLeft / MetaRight
Alt	Option / ⌥	Alt	AltLeft / AltRight
Control	Control / ^	Control	ControlLeft / ControlRight
Shift	Shift	Shift	ShiftLeft / ShiftRight
Space	Space	N/A	Space
Enter	Return	Enter	Enter
Esc	Esc	Escape	Escape
1, 2, etc	1, 2, etc	1, 2, etc	Digit1, Digit2, etc
a, b, etc	a, b, etc	a, b, etc	KeyA, KeyB, etc
-	-	-	Minus
=	=	=	Equal
+	+	+	Equal*

Something missing? Check out the key logger on the demo website

* Some keys will have the same code as others because they appear on the same key on the keyboard. Keep in mind how this is affected by international keyboards which may have different layouts.

Key aliases

In some instances, tinykeys will alias keys depending on the platform to simplify cross-platform keybindings on international keyboards.

AltGraph (modifier)

On Windows, on many non-US standard keyboard layouts, there is a key named Alt Gr or AltGraph in the browser, in some browsers, pressing Control+Alt will report AltGraph as being pressed instead.

Similarly on macOS, the Alt (Option) key will sometimes be reported as the AltGraph key.

Note: The purpose of the Alt Gr key is to type "Alternate Graphics" so you will often want to use the event.code (KeyS) for letters instead of event.key (S)

tinykeys(window, {
  "Control+Alt+KeyS": event => {
    // macOS: `Control+Alt+S` or `Control+AltGraph+S`
    // Windows: `Control+Alt+S` or `Control+AltGraph+S` or `AltGraph+S`
  },
  "$mod+Alt+KeyS": event => {
    // macOS: `Meta+Alt+S` or `Meta+AltGraph+S`
    // Windows: `Control+Alt+S` or `Control+AltGraph+S` or `AltGraph+S`
  },
})

Keybinding Syntax

Keybindings are made up of a sequence of presses.

A press can be as simple as a single key which matches against KeyboardEvent.code and KeyboardEvent.key (case-insensitive).

// Matches `event.key`:
"d"
// Matches: `event.code`:
"KeyD"

Presses can optionally be prefixed with modifiers which match against any valid value to KeyboardEvent.getModifierState().

"Control+d"
"Meta+d"
"Shift+D"
"Alt+KeyD"
"Meta+Shift+D"

There is also a special $mod modifier that makes it easy to support cross platform keybindings:

• Mac: $mod = Meta (⌘)
• Windows/Linux: $mod = Control

"$mod+D" // Meta/Control+D
"$mod+Shift+D" // Meta/Control+Shift+D

Keybinding Sequences

Keybindings can also consist of several key presses in a row:

"g i" // i.e. "Go to Inbox"
"g a" // i.e. "Go to Archive"
"ArrowUp ArrowUp ArrowDown ArrowDown ArrowLeft ArrowRight ArrowLeft ArrowRight B A"

Each press can optionally be prefixed with modifier keys:

"$mod+K $mod+1" // i.e. "Toggle Level 1"
"$mod+K $mod+2" // i.e. "Toggle Level 2"
"$mod+K $mod+3" // i.e. "Toggle Level 3"

Each press in the sequence must be pressed within 1000ms of the last.

Display the keyboard sequence

You can use the parseKeybinding method to get a structured representation of a keyboard shortcut. It can be useful when you want to display it in a fancier way than a plain string.

import { parseKeybinding } from "tinykeys"

let parsedShortcut = parseKeybinding("$mod+Shift+K $mod+1")

Results into:

[
  [["Meta", "Shift"], "K"],
  [["Meta"], "1"],
]

Additional Configuration Options

You can configure the behavior of tinykeys in a couple ways using a third options parameter.

tinykey(
  window,
  {
    M: toggleMute,
  },
  {
    event: "keyup",
  },
)

options.event

Valid values: "keydown", "keyup"

Key presses will listen to this event (default: "keydown").

Note: Do not pass "keypress", it is deprecated in browsers.

options.timeout

Keybinding sequences will wait this long between key presses before cancelling (default: 1000).

Note: Setting this value too low (i.e. 300) will be too fast for many of your users.