react-table how create column headers and cells with array

Question

i'm using react-table in my project and i wonder how create headers dynamically with array.

in my component i have:

const columns = [
  {Header: 'day', accessor: ''}, 
  {Header: 'day', accessor: ''}
]

<ReactTable
    className="-striped -highlight"
    data={this.props.items}
    columns={columns}
    defaultPageSize={20}/>

and i have json data like that:

"items": [
    {
      "day": "01",
      "city": "A",
      "1": "",
      "2": "",
      "3": "",
      "4": null,
      "5": "",
      "6": 256,
      "7": 36.07,
      "8": 35.15,
      "9": "",
      "10": "",
      "11": 6.49,
      "12": 5.9,
      "13": "",
      "14": "",
      "15": 72.0,
      "16": 62.109375,
      "17": 266.78,
      "18": 83.59375,
      "19": 444.96
    },
    {
      "day": "02",
      "city": "B",
      "1": "",
      "2": "",
      "3": "",
      "4": null,
      "5": "",
      "6": 234,
      "7": 36.52,
      "8": 35.6,
      "9": "",
      "10": "",
      "11": 6.08,
      "12": 5.71,
      "13": "",
      "14": "",
      "15": 64.0,
      "16": 43.162393162393165,
      "17": 121.97,
      "18": 84.1880341880342,
      "19": 346.49
    },
    {
      "day": "03",
      "city": "B",
      "1": "",
      "2": "",
      "3": "",
      "4": null,
      "5": "",
      "6": 221,
      "7": 36.96,
      "8": 35.93,
      "9": "",
      "10": "",
      "11": 5.82,
      "12": 5.28,
      "13": "",
      "14": "",
      "15": 56.99999999999999,
      "16": 39.366515837104075,
      "17": 94.48,
      "18": 78.28054298642535,
      "19": 227.4
    },
   ]

so here is i want to make each item in items array will have column. and these columns headers will be their day property and cells will be values which in list 1, 2, 3, 5, 6. How can i do that ?

Orlyyn · Accepted Answer · 2019-03-07 09:23:05Z

3

You could just have a loop in a function to dynamically create the headers you need based on the first object of your items list :

getColumns () {
  let columns = [];
  let headers = Object.keys(items[0]);
  headers.forEach(header => {
    columns.push({
      Header: header
      accessor: ""
    })
  }

  return columns;
}

Hope it is what you were looking for (unless I didn't understand the question).

UPDATE

The first thing to do is to build the rows array to fit the way you want to display them. Indeed, the items array should be transformed into something like this :

[{
  "day01": "A",
  "day02": "B",
  "day03": "B"
},
{...}]

It can be done like this :

  render () {
    const rows = this.buildDataFromItems(items);   // items is your json array
    const columns = this.buildColumnsFromItems(items);
    return(
      <ReactTable
        columns={columns}
        data={rows}
      />
    )
  }

  buildColumnsFromItems (items) {
    let headers = [];
    items.forEach(item => {
      headers.push("day" + item.day);
    })

    let columns = [];
    headers.forEach(header => {
      columns.push({
        Header: header,
        accessor: header
      })
    });

    return columns;
  }

  buildDataFromItems (items) {
    let rows = [];
    let currentHeader = "";
    let currentRow = {};

    for (let i = 0; i < Object.keys(items[0]).length && Object.keys(items[0])[i] !== "day"; i++) {
      currentRow = {};
      items.forEach(item => {
        currentHeader = "day" + item.day;
        currentRow[currentHeader] = item[Object.keys(items[0])[i]];
      })

      rows.push(currentRow);
    }

    return rows;
  }

This piece of code should be enough to lead you to your final solution I hope :)

edited Mar 7, 2019 at 9:23

answered Mar 6, 2019 at 14:13

Orlyyn

2,6222 gold badges25 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

user3348410 Over a year ago

Thank you for your answer, and sorry for my bad explanation. I want to make each column will take one item in array so column header will be day01 property and from top to bottom will ordered another values. order will be like in json data, just each column will take one item in this array. From top to bottom, another item will be another column, next item will be another..

Orlyyn Over a year ago

Ooh so you want actually the header to be the first attribute of each item ? Like first column has header day01 with values listed below, then second header is day02 etc ? Then, as a value, what do you wish to display ? the keys concatenated to their values (ex: cityB) or just the given value ? (ex: B)

user3348410 Over a year ago

yes header will be 'day' and cell values of this column will be "1": "", "2": "", "3": "", "4": null, "5": "", "6": 221, "7": 36.96, "8": 35.93, "9": "", "10": "", "11": 5.82, "12": 5.28, "13": "", "14": "", "15": 56.99999999999999, "16": 39.366515837104075, "17": 94.48, "18": 78.28054298642535, "19": 227.4 , from top to bottom

Orlyyn Over a year ago

@user3348410 I added a piece of code to match the rows construction that needs to be done, based on your items array. Tell me if this is clear for you ! :)

user3348410 Over a year ago

thanks you so much! it's worked well and i understand the concept :)

Collectives™ on Stack Overflow

react-table how create column headers and cells with array

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related