How to prevent events from acting in nested divs when using React Hooks

Question

I have nested div elements. Outside there should be events to move and to click. I want to enable a nested element to act as a button and to prevent the event from outside to act. In the example when we click on the red part, both events are happening. How can I stop the event from the green part when we click on the red part? stopPropagation() did not do the job. I am using React and my structure is more complex than in the example. But I wanted to reduce for reasons of clarity.

I would be happy if someone can help.

#bigCircle {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background-color: green;
}

#smallCircle {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: red;
}

<!DOCTYPE html>
<html lang="en">

<head>
</head>

<body>
  <div id="bigCircle">
    <div id="smallCircle"></div>
  </div>
  
  <script>
  document.getElementById("bigCircle").addEventListener("click",myBigCircle);
  
    document.getElementById("smallCircle").addEventListener("click",mySmallCircle);
  
  function myBigCircle(){
  console.log("Hello");}
  
    function mySmallCircle(){
  console.log("Bye");}
  </script>
</body>

</html>

I think it is related to React Hooks. Here you see the example with stopPropagation not working:

import React, { useState } from 'react';

function Test() {
    let [test, setTest] = useState(false);


    return (
        <div id="wrapper"
            style={styleBigCircle}
            onMouseUp={() => {
                setTest(false);
                console.log("Hello", test)
            }
            }>

            <div id="center"
                style={styleSmallCircle}
                onClick={(e) => {
                    e.stopPropagation();
                    setTest(!test);
                    console.log("Bye", test)
                }}
            >

            </div>

        </div>

    );
}

const styleBigCircle = {
    display: "flex",
    justifyContent: "center",
    alignItems: "center",
    width: "180px",
    height: "180px",
    borderRadius: "50%",
    backgroundColor: "green"
}

const styleSmallCircle = {
    width: "40px",
    height: "40px",
    borderRadius: "50%",
    backgroundColor: "red"
}

export default Test;

I would be happy if someone knows how to fix this.

*stopPropagation() did not do the job* It should. Please post the code where you tried to use it — CertainPerformance, Feb 19 '20 at 10:24

score 1 · Answer 1 · answered Feb 19 '20 at 10:28

Use event.stopPropagation() to prevent parent trigger.

#bigCircle {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  background-color: green;
}

#smallCircle {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: red;
}

<!DOCTYPE html>
<html lang="en">

<head>
</head>

<body>
  <div id="bigCircle">
    <div id="smallCircle"></div>
  </div>
  
  <script>
  document.getElementById("bigCircle").addEventListener("click",myBigCircle);
  
    document.getElementById("smallCircle").addEventListener("click",mySmallCircle);
  
  function myBigCircle(){
  console.log("Hello");}
  
    function mySmallCircle(event){
     event.stopPropagation()
     console.log("Bye");
   }
  </script>
</body>

</html>

a--m · Accepted Answer · 2020-02-19T12:54:51.817

You are dealing with different events, so to prevent the child element from trigger the parent you would need to add the same event and stopPropagation() on that one instead:

<div
    id="center"
    style={styleSmallCircle}
    onMouseUp={e => {
      e.stopPropagation();
    }}
    onClick={e => {
      setTest(!test);
      console.log("Bye");
    }}
/>

Here is a fully working example:

const Test = () => {
  let [test, setTest] = React.useState(false);

  return (
    <div
      id="wrapper"
      style={styleBigCircle}
      onMouseUp={() => {
        console.log("Hello");
      }}
    >
      <div
        id="center"
        style={styleSmallCircle}
        onMouseUp={e => {
          e.stopPropagation();
        }}
        onClick={e => {
          console.log("Bye");
        }}
      />
    </div>
  );
};

const styleBigCircle = {
  display: "flex",
  justifyContent: "center",
  alignItems: "center",
  width: "180px",
  height: "180px",
  borderRadius: "50%",
  backgroundColor: "green"
};

const styleSmallCircle = {
  width: "40px",
  height: "40px",
  borderRadius: "50%",
  backgroundColor: "red"
};

const rootElement = document.getElementById("root");
ReactDOM.render(<Test />, rootElement);

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.12.0/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.12.0/umd/react-dom.production.min.js"></script>


<div id="root"></div>

How to prevent events from acting in nested divs when using React Hooks

2 Answers2