React Data GridRow pre-populating

Populate newly-added rows with predefined template values, using cell renderers.

Example
Related API reference

Example

The example below shows how cell renderers can be used to populate the template values in empty rows. When a cell in the empty row is edited, the beforeChange callback fills the row with the template values.

{
  "name": "handsontable",
  "version": "1.0.0",
  "description": "",
  "dependencies": {
    "react": "^18.2.0",
    "react-dom": "^18.2.0",
    "hyperformula": "^2.4.0",
    "handsontable": "14.6",
    "@handsontable/react": "14.6"
  },
  
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
}

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Handsontable</title>
  </head>

  <body>
    <noscript> You need to enable JavaScript to run this app. </noscript>
    <div id="root"></div>
  </body>
</html>

import React, { StrictMode } from "react";
import { createRoot } from "react-dom/client";
import "./styles.css";
import ExampleComponent from "./ExampleComponent";

const rootElement = document.getElementById("root");
const root = createRoot(rootElement);

root.render(
  <StrictMode>
    <ExampleComponent />
  </StrictMode>
);

import React from "react";
import { useRef } from 'react';
import { HotTable } from '@handsontable/react';
import { registerAllModules } from 'handsontable/registry';
import { textRenderer } from 'handsontable/renderers/textRenderer';
import 'handsontable/dist/handsontable.full.min.css';

// register Handsontable's modules
registerAllModules();

const ExampleComponent = () => {
  const hotRef = useRef(null);
  const templateValues = ['one', 'two', 'three'];
  const data = [
    ['', 'Tesla', 'Nissan', 'Toyota', 'Honda'],
    ['2017', 10, 11, 12, 13],
    ['2018', 20, 11, 14, 13],
    ['2019', 30, 15, 12, 13],
  ];

  function isEmptyRow(instance, row) {
    const rowData = instance.getDataAtRow(row);

    for (let i = 0, ilen = rowData.length; i < ilen; i++) {
      if (rowData[i] !== null) {
        return false;
      }
    }

    return true;
  }

  function defaultValueRenderer(instance, td, row, col) {
    const args = arguments;

    if (args[5] === null && isEmptyRow(instance, row)) {
      args[5] = templateValues[col];
      td.style.color = '#999';
    } else {
      td.style.color = '';
    }

    textRenderer.apply(this, args);
  }

  return (
    <>
      <HotTable
        ref={hotRef}
        data={data}
        startRows={8}
        startCols={5}
        minSpareRows={1}
        contextMenu={true}
        height="auto"
        autoWrapRow={true}
        autoWrapCol={true}
        licenseKey="non-commercial-and-evaluation"
        cells={function (row, col, prop) {
          const cellProperties = {};

          cellProperties.renderer = defaultValueRenderer;

          return cellProperties;
        }}
        beforeChange={function (changes) {
          const instance = hotRef.current?.hotInstance;
          const columns = instance?.countCols() || 0;
          const rowColumnSeen = {};
          const rowsToFill = {};

          for (let i = 0; i < changes.length; i++) {
            const cellChanges = changes;

            // if oldVal is empty
            if (cellChanges[i][2] === null && cellChanges[i][3] !== null) {
              if (isEmptyRow(instance, cellChanges[i][0])) {
                // add this row/col combination to the cache so it will not be overwritten by the template
                rowColumnSeen[
                  `${cellChanges[i][0]}/${cellChanges[i][1]}`
                ] = true;
                rowsToFill[cellChanges[i][0]] = true;
              }
            }
          }

          for (const r in rowsToFill) {
            if (rowsToFill.hasOwnProperty(r)) {
              for (let c = 0; c < columns; c++) {
                // if it is not provided by user in this change set, take the value from the template
                if (!rowColumnSeen[`${r}/${c}`]) {
                  changes.push([r, c, null, templateValues[c]]);
                }
              }
            }
          }
        }}
      />
    </>
  );
};

export default ExampleComponent;

import { useRef } from 'react';
import { HotTable } from '@handsontable/react';
import { registerAllModules } from 'handsontable/registry';
import { textRenderer } from 'handsontable/renderers/textRenderer';
import 'handsontable/dist/handsontable.full.min.css';

// register Handsontable's modules
registerAllModules();

const ExampleComponent = () => {
  const hotRef = useRef(null);
  const templateValues = ['one', 'two', 'three'];
  const data = [
    ['', 'Tesla', 'Nissan', 'Toyota', 'Honda'],
    ['2017', 10, 11, 12, 13],
    ['2018', 20, 11, 14, 13],
    ['2019', 30, 15, 12, 13],
  ];

  function isEmptyRow(instance, row) {
    const rowData = instance.getDataAtRow(row);

    for (let i = 0, ilen = rowData.length; i < ilen; i++) {
      if (rowData[i] !== null) {
        return false;
      }
    }

    return true;
  }

  function defaultValueRenderer(instance, td, row, col) {
    const args = arguments;

    if (args[5] === null && isEmptyRow(instance, row)) {
      args[5] = templateValues[col];
      td.style.color = '#999';
    } else {
      td.style.color = '';
    }

    textRenderer.apply(this, args);
  }

  return (
    <>
      <HotTable
        ref={hotRef}
        data={data}
        startRows={8}
        startCols={5}
        minSpareRows={1}
        contextMenu={true}
        height="auto"
        autoWrapRow={true}
        autoWrapCol={true}
        licenseKey="non-commercial-and-evaluation"
        cells={function (row, col, prop) {
          const cellProperties = {};

          cellProperties.renderer = defaultValueRenderer;

          return cellProperties;
        }}
        beforeChange={function (changes) {
          const instance = hotRef.current?.hotInstance;
          const columns = instance?.countCols() || 0;
          const rowColumnSeen = {};
          const rowsToFill = {};

          for (let i = 0; i < changes.length; i++) {
            const cellChanges = changes;

            // if oldVal is empty
            if (cellChanges[i][2] === null && cellChanges[i][3] !== null) {
              if (isEmptyRow(instance, cellChanges[i][0])) {
                // add this row/col combination to the cache so it will not be overwritten by the template
                rowColumnSeen[
                  `${cellChanges[i][0]}/${cellChanges[i][1]}`
                ] = true;
                rowsToFill[cellChanges[i][0]] = true;
              }
            }
          }

          for (const r in rowsToFill) {
            if (rowsToFill.hasOwnProperty(r)) {
              for (let c = 0; c < columns; c++) {
                // if it is not provided by user in this change set, take the value from the template
                if (!rowColumnSeen[`${r}/${c}`]) {
                  changes.push([r, c, null, templateValues[c]]);
                }
              }
            }
          }
        }}
      />
    </>
  );
};



ReactDOM.render(<ExampleComponent />, document.getElementById("example1"));

<script src="https://cdn.jsdelivr.net/npm/handsontable@14.6/dist/handsontable.full.min.js"></script>
<link type="text/css" rel="stylesheet" href="https://cdn.jsdelivr.net/npm/handsontable@14.6/dist/handsontable.full.min.css" /> 
<script src="https://cdn.jsdelivr.net/npm/react@17/umd/react.production.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/react-dom@17/umd/react-dom.production.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/@handsontable/react@14.6/dist/react-handsontable.min.js"></script>
<script src="https://handsontable.com/docs/scripts/fixer.js"></script>

<div id="example1" class="hot "></div>

import { useRef } from 'react';
import { HotTable } from '@handsontable/react';
import { registerAllModules } from 'handsontable/registry';
import { textRenderer } from 'handsontable/renderers/textRenderer';
import 'handsontable/dist/handsontable.full.min.css';

// register Handsontable's modules
registerAllModules();

const ExampleComponent = () => {
  const hotRef = useRef(null);
  const templateValues = ['one', 'two', 'three'];
  const data = [
    ['', 'Tesla', 'Nissan', 'Toyota', 'Honda'],
    ['2017', 10, 11, 12, 13],
    ['2018', 20, 11, 14, 13],
    ['2019', 30, 15, 12, 13],
  ];

  function isEmptyRow(instance, row) {
    const rowData = instance.getDataAtRow(row);

    for (let i = 0, ilen = rowData.length; i < ilen; i++) {
      if (rowData[i] !== null) {
        return false;
      }
    }

    return true;
  }

  function defaultValueRenderer(instance, td, row, col) {
    const args = arguments;

    if (args[5] === null && isEmptyRow(instance, row)) {
      args[5] = templateValues[col];
      td.style.color = '#999';
    } else {
      td.style.color = '';
    }

    textRenderer.apply(this, args);
  }

  return (
    <>
      <HotTable
        ref={hotRef}
        data={data}
        startRows={8}
        startCols={5}
        minSpareRows={1}
        contextMenu={true}
        height="auto"
        autoWrapRow={true}
        autoWrapCol={true}
        licenseKey="non-commercial-and-evaluation"
        cells={function (row, col, prop) {
          const cellProperties = {};

          cellProperties.renderer = defaultValueRenderer;

          return cellProperties;
        }}
        beforeChange={function (changes) {
          const instance = hotRef.current?.hotInstance;
          const columns = instance?.countCols() || 0;
          const rowColumnSeen = {};
          const rowsToFill = {};

          for (let i = 0; i < changes.length; i++) {
            const cellChanges = changes;

            // if oldVal is empty
            if (cellChanges[i][2] === null && cellChanges[i][3] !== null) {
              if (isEmptyRow(instance, cellChanges[i][0])) {
                // add this row/col combination to the cache so it will not be overwritten by the template
                rowColumnSeen[
                  `${cellChanges[i][0]}/${cellChanges[i][1]}`
                ] = true;
                rowsToFill[cellChanges[i][0]] = true;
              }
            }
          }

          for (const r in rowsToFill) {
            if (rowsToFill.hasOwnProperty(r)) {
              for (let c = 0; c < columns; c++) {
                // if it is not provided by user in this change set, take the value from the template
                if (!rowColumnSeen[`${r}/${c}`]) {
                  changes.push([r, c, null, templateValues[c]]);
                }
              }
            }
          }
        }}
      />
    </>
  );
};

export default ExampleComponent;

Hooks:
- beforeChange

React Data GridRow pre-populating

Example

Related API reference