I have an array of data that will be used to create accordions, I'd like to make it so that only one of them can be expanded at once (i.e, if the user expands accordion #1 and then #2, #1 will un-expand)

I have this code:

const MyAccordion = props => {
    const [expanded, setExpanded] = React.useState()
    const handleChange = panel => (_, isExpanded) => {setExpanded(isExpanded ? panel : false)}
    const classes = styles //?
    let accordionInfo = createAccordionInfo(props.propthing);
    return (
        <Accordion
            key={accordionInfo.uid}
            onChange={handleChange(accordionInfo.uid)}
            expanded={expanded === accordionInfo.uid}
            TransitionProps={{unmountOnExit: true}}
            className={classes.accordion}
        >
            <AccordionSummary expandIcon={<ExpandMoreIcon />} aria-controls={`${accordionInfo.uid}-content`} id={`${accordionInfo.uid}-header`}>
                <Typography>Accordion Summary</Typography>
            </AccordionSummary>

            <AccordionDetails>
                <Typography>Accordion Details</Typography>
            </AccordionDetails>
        </Accordion>
    )
}

const MyAccordions = props => {
    const [expanded, setExpanded] = React.useState()
    const handleChange = panel => (_, isExpanded) => {setExpanded(isExpanded ? panel : false)}
    return (
        <div className={styles.root}>
            {accordions.map(accordion => (
                <MyAccordion onChange={handleChange} propthing={accordion} />
            ))}
        </div>
    )
}

I'm quite new to React so I suspect I've made a mistake with the states. Any help / tips would be appreciated! Thank you

I have an array of data that will be used to create accordions, I'd like to make it so that only one of them can be expanded at once (i.e, if the user expands accordion #1 and then #2, #1 will un-expand)

I have this code:

const MyAccordion = props => {
    const [expanded, setExpanded] = React.useState()
    const handleChange = panel => (_, isExpanded) => {setExpanded(isExpanded ? panel : false)}
    const classes = styles //?
    let accordionInfo = createAccordionInfo(props.propthing);
    return (
        <Accordion
            key={accordionInfo.uid}
            onChange={handleChange(accordionInfo.uid)}
            expanded={expanded === accordionInfo.uid}
            TransitionProps={{unmountOnExit: true}}
            className={classes.accordion}
        >
            <AccordionSummary expandIcon={<ExpandMoreIcon />} aria-controls={`${accordionInfo.uid}-content`} id={`${accordionInfo.uid}-header`}>
                <Typography>Accordion Summary</Typography>
            </AccordionSummary>

            <AccordionDetails>
                <Typography>Accordion Details</Typography>
            </AccordionDetails>
        </Accordion>
    )
}

const MyAccordions = props => {
    const [expanded, setExpanded] = React.useState()
    const handleChange = panel => (_, isExpanded) => {setExpanded(isExpanded ? panel : false)}
    return (
        <div className={styles.root}>
            {accordions.map(accordion => (
                <MyAccordion onChange={handleChange} propthing={accordion} />
            ))}
        </div>
    )
}

I'm quite new to React so I suspect I've made a mistake with the states. Any help / tips would be appreciated! Thank you

• javascript
• reactjs
• jsx

1 Answer 1

It looks like you tried putting state and handlers in both the parent MyAccordions and the children MyAccordion ponents. If you want only one accordion open at-a-time then I suggest placing the state in the parent ponent so it can manage what is open/expanded. Use the children accordion ids as the basis of determining which should expand.

Parent

const MyAccordions = props => {
  const [expanded, setExpanded] = React.useState(null);

  const handleChange = id => (_, isExpanded) => {
    // if expanded, set id to open/expand, close it otherwise 
    setExpanded(isExpanded ? id: null);
  };

  return (
    <div className={styles.root}>
      {accordions.map(accordion => {
        const info = createAccordionInfo(accordion);
        return (
          <MyAccordion
            key={info.uid} // <-- set React key here!!
            onChange={handleChange(info.uid)}
            expanded={expanded === info.uid}
          />
        )
      })}
    </div>
  );
};

Child

const MyAccordion =({ expanded, onChange }) => {
  const classes = styles //?

  return (
    <Accordion
      onChange={onChange}
      expanded={expanded}
      TransitionProps={{unmountOnExit: true}}
      className={classes.accordion}
    >
      <AccordionSummary
        expandIcon={<ExpandMoreIcon />}
        aria-controls={`${accordionInfo.uid}-content`}
        id={`${accordionInfo.uid}-header`}
      >
        <Typography>Accordion Summary</Typography>
      </AccordionSummary>

      <AccordionDetails>
        <Typography>Accordion Details</Typography>
      </AccordionDetails>
    </Accordion>
  );
};