I have a component (selector) which contains a checkbox and another div (selectorPane).

The checkbox state controls the selectorPane visibility (by assigning/not-assigning the ‘visible’ css class).

This works fine, the problem comes when i try to make selectorPane invisible (set checkbox.checked = false) on selectorPane.onBlur() event… in other words, close selectorPane when clicking outside.

This is the working code (without the ‘click outside to close‘ functionality).

import { useEffect, useRef, useState } from "react"

import "./Selector.css"

export default function Selector() {
  //reference selector-pane for programatic focus
  const selectorPaneRef = useRef<HTMLDivElement | null>(null);

  const [ selectorPaneVisible, setSelectorPaneVisible ] = useState(false);

  const handleCheckboxStateChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const checkbox = e.target as HTMLInputElement;
    setSelectorPaneVisible(checkbox.checked);
  }

  //autofocus selector-pane when rendering with selectorPaneVisible = true
  useEffect(() => {
    if (selectorPaneVisible && !!selectorPaneRef.current) {
      selectorPaneRef.current.focus();
    }
  }, [selectorPaneVisible])

  return (
    <div className="selector">
      <input
        type="checkbox"
        checked={selectorPaneVisible}
        onChange={handleCheckboxStateChange}
      />
      <div
        className={`selector-pane ${selectorPaneVisible ? "visible" : ""}`}
        tabIndex={-1}
      >
        content content content content
      </div>
    </div>
  )
}

note: autofocus functionality is not used here, but is kept to demonstrate it doesn’t add a bug

Here is the NOT-WORKING example:

It has added the onBlur (function: handleSelectorPaneBlur) event for the selectorPane div which performs a setSelectorPaneVisible(false)

import { useEffect, useRef, useState } from "react";

import "./Selector.css";

export default function Selector() {
  //reference selector-pane for programatic focus
  const selectorPaneRef = useRef<HTMLDivElement | null>(null);

  const [selectorPaneVisible, setSelectorPaneVisible] = useState(false);

  const handleCheckboxStateChange = (
    e: React.ChangeEvent<HTMLInputElement>
  ) => {
    const checkbox = e.target as HTMLInputElement;
    setSelectorPaneVisible(checkbox.checked);
  };

  const handleSelectorPaneBlur = () => {
    setSelectorPaneVisible(false);
  };

  //autofocus selector-pane when render with selectorPaneVisible = true
  useEffect(() => {
    if (selectorPaneVisible && !!selectorPaneRef.current) {
      selectorPaneRef.current.focus();
    }
  }, [selectorPaneVisible]);

  return (
    <div className="selector">
      <input
        type="checkbox"
        checked={selectorPaneVisible}
        onChange={handleCheckboxStateChange}
      />
      <div
        className={`selector-pane ${selectorPaneVisible ? "visible" : ""}`}
        tabIndex={-1}
        ref={selectorPaneRef}
        onBlur={handleSelectorPaneBlur}
      >
        content content content content
      </div>
    </div>
  );
}

By default the checkbox is unchecked, so the selectorPane is invisible

• on first click is checks correctly, shows the div, and it autofocuses
• if i click outside the pane (anywhere), it unchecks and hides de pane well
• the problem is that i cant hide the pane by clicking on the checkbox itself (it flashes unchecked & checked again instantly)

This is the CSS:

.selector > div {
  background-color: green;
}
.selector > div:focus {
  background-color: red;
}

.selector > div {
  visibility: hidden;
}
.selector > div.visible {
  visibility: visible;
}

I tested creating a ref to the checkbox element to uncheck it by firing a programatic click event

const checkboxRef = useRef<HTMLInputElement | null>(null)

<input 
  type="checkbox" 
  checked={selectorPaneVisible} 
  onChange={handleCheckboxStateChange} 
  ref={checkboxRef} 
/>

const handleSelectorPaneBlur = () => {
  if (checkboxRef.current) {
    checkboxRef.current.click();
  }
}

but the result is the same (unchecks & checks again in a flash)

• The handleCheckboxStateChange function is fired only ONCE when I click the checkbox to uncheck it