Hover Card

An hover card allows sighted users to preview content available behind a link

Properties

openDelay

closeDelay

Features

Customize side, alignment, offsets
Optionally render a pointing arrow.
Supports custom open and close delays.
Opens on hover only.
Ignored by screen readers.

Installation

To use the hover card machine in your project, run the following command in your command line:

npm install @zag-js/hover-card @zag-js/react
# or
yarn add @zag-js/hover-card @zag-js/react

npm install @zag-js/hover-card @zag-js/solid
# or
yarn add @zag-js/hover-card @zag-js/solid

npm install @zag-js/hover-card @zag-js/vue
# or
yarn add @zag-js/hover-card @zag-js/vue

npm install @zag-js/hover-card @zag-js/vue
# or
yarn add @zag-js/hover-card @zag-js/vue

This command will install the framework agnostic hover card logic and the reactive utilities for your framework of choice.

Anatomy

To set up the hover card correctly, you'll need to understand its anatomy and how we name its parts.

Each part includes a data-part attribute to help identify them in the DOM.

Usage

First, import the hover card package into your project

import * as hoverCard from "@zag-js/hover-card"

The hover card package exports two key functions:

machine — The state machine logic for the hover card widget.
connect — The function that translates the machine's state to JSX attributes and event handlers.

Next, import the required hooks and functions for your framework and use the hover-card machine in your project 🔥

import * as hoverCard from "@zag-js/hover-card"
import { useMachine, normalizeProps, Portal } from "@zag-js/react"

function HoverCard() {
  const [state, send] = useMachine(hoverCard.machine({ id: "1" }))

  const api = hoverCard.connect(state, send, normalizeProps)

  return (
    <>
      <a
        href="https://twitter.com/zag_js"
        target="_blank"
        {...api.triggerProps}
      >
        Twitter
      </a>

      {api.open && (
        <Portal>
          <div {...api.positionerProps}>
            <div {...api.contentProps}>
              <div {...api.arrowProps}>
                <div {...api.arrowTipProps} />
              </div>
              Twitter Preview
            </div>
          </div>
        </Portal>
      )}
    </>
  )
}

import * as hoverCard from "@zag-js/hover-card"
import { normalizeProps, useMachine } from "@zag-js/solid"
import { createMemo, createUniqueId, Show } from "solid-js"
import { Portal } from "solid-js/web"

function Checkbox() {
  const [state, send] = useMachine(hoverCard.machine({ id: "1" }))

  const api = hoverCard.connect(state, send, normalizeProps)

  return (
    <>
      <a
        href="https://twitter.com/zag_js"
        target="_blank"
        {...api().triggerProps}
      >
        Twitter
      </a>

      <Show when={api().open}>
        <Portal>
          <div {...api().positionerProps}>
            <div {...api().contentProps}>
              <div {...api().arrowProps}>
                <div {...api().arrowTipProps} />
              </div>
              Twitter Preview
            </div>
          </div>
        </Portal>
      </Show>
    </>
  )
}

import * as hoverCard from "@zag-js/hover-card"
import { normalizeProps, useMachine } from "@zag-js/vue"
import { defineComponent, h, Fragment, computed, Teleport } from "vue"

export default defineComponent({
  name: "HoverCard",
  setup() {
    const [state, send] = useMachine(hoverCard.machine({ id: "hoverCard" }))

    const apiRef = computed(() =>
      hoverCard.connect(state.value, send, normalizeProps),
    )

    return () => {
      const api = apiRef.value
      return (
        <>
          <a
            href="https://twitter.com/zag_js"
            target="_blank"
            {...api.triggerProps}
          >
            Twitter
          </a>

          {api.open && (
            <Teleport to="body">
              <div {...api.positionerProps}>
                <div {...api.contentProps}>
                  <div {...api.arrowProps}>
                    <div {...api.arrowTipProps} />
                  </div>
                  Twitter Preview
                </div>
              </div>
            </Teleport>
          )}
        </>
      )
    }
  },
})

<script setup>
import * as hoverCard from "@zag-js/hover-card"
import { normalizeProps, useMachine } from "@zag-js/vue"
import { computed, Teleport } from "vue"

const [state, send] = useMachine(hoverCard.machine({ id: "1" }))

const api = computed(() => hoverCard.connect(state.value, send, normalizeProps))
</script>

<template>
  <a 
    href="https://twitter.com/zag_js"
    target="_blank" 
    v-bind="api.triggerProps"
  >
    Twitter
  </a>
  <Teleport to="body" v-if="api.open">
    <div v-bind="api.positionerProps">
      <div v-bind="api.contentProps">
        <div v-bind="api.arrowProps">
          <div v-bind="api.arrowTipProps" />
        </div>
        Twitter Preview
      </div>
    </div>
  </Teleport>
</template>

Making it opened initially

To make an hover card open by default, set the context's open property to true

const [state, send] = useMachine(
  hoverCard.machine({
    open: true,
  }),
)

Listening for open state changes

When the hover card is opened or closed, the onOpenChange callback is invoked.

const [state, send] = useMachine(
  hoverCard.machine({
    onOpenChange(details) {
      // details => { open: boolean }
      console.log("hovercard is:", details.open ? "opened" : "closed")
    },
  }),
)

Styling guide

Earlier, we mentioned that each hover card part has a data-part attribute added to them to select and style them in the DOM.

[data-part="trigger"] {
  /* styles for trigger */
}

[data-part="content"] {
  /* styles for content */
}

Open and closed state

The hover card exposes a data-state attribute that can be used to style the hover card based on its open-close state.

[data-part="trigger"][data-state="open|closed"] {
  /* styles for open or closed state */
}

[data-part="content"][data-state="open|closed"] {
  /* styles for open or closed state */
}

Arrow

Zag exposes some variable that can be used to style the arrow.

[data-part="arrow"] {
  /* styles for arrow */
  --arrow-background: white;
  --arrow-size: 8px;
}

[data-part="content"] {
  /* styles for content */
}

Methods and Properties

Machine Context

The hover card machine exposes the following context properties:

idsPartial<{ trigger: string; content: string; positioner: string; arrow: string; }>The ids of the elements in the popover. Useful for composition.

onOpenChange(details: OpenChangeDetails) => voidFunction called when the hover card opens or closes.

openDelaynumberThe duration from when the mouse enters the trigger until the hover card opens.

closeDelaynumberThe duration from when the mouse leaves the trigger or content until the hover card closes.

openbooleanWhether the hover card is open

open.controlledbooleanWhether the hover card is controlled by the user

positioningPositioningOptionsThe user provided options used to position the popover content

dir"ltr" | "rtl"The document's text/writing direction.

idstringThe unique identifier of the machine.

getRootNode() => ShadowRoot | Node | DocumentA root node to correctly resolve document in custom environments. E.x.: Iframes, Electron.

Machine API

The hover card api exposes the following methods:

openbooleanWhether the hover card is open

setOpen(open: boolean) => voidFunction to open the hover card

reposition(options?: Partial<PositioningOptions>) => voidFunction to reposition the popover

Data Attributes

Trigger

data-scope

hover-card

data-part

trigger

data-placement

The placement of the trigger

data-state

"open" | "closed"

Content