HTML Hack – Making Any Element Focusable

Recently I have been working on making a simple snake game and wanted to know what my options were for capturing keyboard events other than simply adding event listeners to the body, document, or the window. Amongst the obvious reasons for avoiding adding event listeners globally, I just want to make a prototype that will create one canvas element which will capture keyboard events. After doing a quick Google search I found this awesome article saying that it is possible to make any element focusable.

For example make an element as innocuous as a <div> element focusable by simply defining it’s tabIndex attribute:

• Clicking on me will give me the focus!
• Clicking on me will do nothing because I have no tabIndex.

The above focusable and non-focusable <div>‘s are produced by this code:

<style type="text/css">
.focusable-test:focus {
  box-shadow: 0 0 5px 1px #08F;
}
</style>
<ul>
  <li><div class="focusable-test" tabindex="1234">Clicking on me will give me the focus!</div></li>
  <li><div class="focusable-test">Clicking on me will do nothing because I have no <code>tabIndex</code>.</div></li>
</ul>

As you can see, only the <div> with a set tabIndex is truly focusable. I plan on using this cool hack to make my game’s canvas focusable. I hope you find this neat trick useful as well! 😎