Skip to content

React DOM events on components

I wanted to show or hide a little panel based on the mouse hover status.

When I hovered a link, the panel would show up.

Then I could enter this panel with the mouse, and when I moved the mouse away, the panel would hide.

Like the Twitter profile that shows when you move the mouse upon the name of a person:

on the <a> element that triggered the panel to show up, I added the event onMouseEnter:

<a
  onMouseEnter={() => {
    setShowCard(true)
  }}
>flavio</a>

so the panel would show when I hovered it with the mouse, because it was shown depending on the showCard state variable I had set before:

const [showCard, setShowCard] = useState(false)

Then I had the ProfileCard component but I couldn’t just do:

<ProfileCard
onMouseEnter={() => {
  setShowCard(true)
}}
onMouseLeave={() => {
  setShowCard(false)
}}
/>

because it didn’t work. ProfileCard is not a DOM element, so it didn’t get the events fired to respond to.

What I had to do was to pass onMouseEnter and onMouseLeave as props to the ProfileCard component, then identify the correct DOM element inside it that could receive those events, and attach the event handler there. In this case, I used the container div:

const ProfileCard = ({
  onMouseEnter,
  onMouseLeave
}) => (
  <div
    onMouseEnter={onMouseEnter}
    onMouseLeave={onMouseLeave}>
      ...

Now leaving the panel would hide it.

→ Download my free React Handbook!

THE VALLEY OF CODE

THE WEB DEVELOPER's MANUAL

You might be interested in those things I do:

  • Learn to code in THE VALLEY OF CODE, your your web development manual
  • Find a ton of Web Development projects to learn modern tech stacks in practice in THE VALLEY OF CODE PRO
  • I wrote 16 books for beginner software developers, DOWNLOAD THEM NOW
  • Every year I organize a hands-on cohort course coding BOOTCAMP to teach you how to build a complex, modern Web Application in practice (next edition February-March-April-May 2024)
  • Learn how to start a solopreneur business on the Internet with SOLO LAB (next edition in 2024)
  • Find me on X

Related posts that talk about react: