Antdpro Table column is not working when state changes

ONLINECAST

3 min read

·

05-10-2024

9

0

Share

Ant Design Pro Table: Troubleshooting State Changes in Columns

Scenario: You're working with Ant Design Pro's Table component and you've encountered a frustrating issue – your table columns aren't dynamically updating when your state changes. You've painstakingly set up your component to react to state changes, but the columns remain stubbornly static.

The Problem: This is a common challenge when working with dynamic UI components. The key is understanding how data flow works within React and Ant Design Pro.

Original Code (Example):

import React, { useState } from 'react';
import { Table } from 'antd';

function MyTable() {
  const [data, setData] = useState([
    { key: 1, name: 'John Doe', age: 30 },
    { key: 2, name: 'Jane Smith', age: 25 },
  ]);

  const [showAgeColumn, setShowAgeColumn] = useState(true);

  const handleToggleAgeColumn = () => {
    setShowAgeColumn(!showAgeColumn);
  };

  const columns = [
    {
      title: 'Name',
      dataIndex: 'name',
      key: 'name',
    },
    ...(showAgeColumn ? [
      {
        title: 'Age',
        dataIndex: 'age',
        key: 'age',
      }
    ] : []),
  ];

  return (
    <div>
      <button onClick={handleToggleAgeColumn}>Toggle Age Column</button>
      <Table columns={columns} dataSource={data} />
    </div>
  );
}

export default MyTable;

Explanation:

In this example, we have a table with two initial rows. We want to conditionally show an 'Age' column based on a state variable showAgeColumn. The columns array is constructed dynamically, adding the 'Age' column only if showAgeColumn is true.

The Issue: While the showAgeColumn state does change when you click the "Toggle Age Column" button, the table columns don't reflect this change. The columns array remains static, and the table renders with the same columns regardless of the state.

Solution: The problem lies in the way React handles state updates. React only re-renders a component if its props or state change. Here, even though the showAgeColumn state changes, the columns array isn't directly updated as a result.

Fixing the Problem:

To ensure that the table columns are updated when the showAgeColumn state changes, we need to use a memoization technique. This technique creates a new columns array every time showAgeColumn changes.

Updated Code:

import React, { useState, useMemo } from 'react';
import { Table } from 'antd';

function MyTable() {
  const [data, setData] = useState([
    { key: 1, name: 'John Doe', age: 30 },
    { key: 2, name: 'Jane Smith', age: 25 },
  ]);

  const [showAgeColumn, setShowAgeColumn] = useState(true);

  const handleToggleAgeColumn = () => {
    setShowAgeColumn(!showAgeColumn);
  };

  const columns = useMemo(() => [
    {
      title: 'Name',
      dataIndex: 'name',
      key: 'name',
    },
    ...(showAgeColumn ? [
      {
        title: 'Age',
        dataIndex: 'age',
        key: 'age',
      }
    ] : []),
  ], [showAgeColumn]); // Pass showAgeColumn as dependency

  return (
    <div>
      <button onClick={handleToggleAgeColumn}>Toggle Age Column</button>
      <Table columns={columns} dataSource={data} />
    </div>
  );
}

export default MyTable;

Explanation:

1. useMemo: This hook allows us to create a memoized version of the columns array. useMemo will only recompute the array if the showAgeColumn dependency changes.

2. Dependency Array: By passing [showAgeColumn] as the dependency array for useMemo, we're telling React to re-evaluate the columns array whenever the showAgeColumn state changes.

Key Takeaway:

By using useMemo, we ensure that the columns array is recreated whenever showAgeColumn changes, triggering a re-render of the table and dynamically updating the displayed columns.

Additional Tips:

• React Development Tools: Utilize the React Developer Tools for Chrome or Firefox to inspect your component tree and understand how state changes are affecting your component rendering.

• Performance Considerations: While useMemo is essential for dynamic updates, use it judiciously. For complex computations, consider other techniques like memoizing individual columns or using React.memo for performance optimization.

Resources:

• Ant Design Pro Table Documentation
• React Hook - useMemo

By understanding how state changes impact component re-rendering and employing techniques like memoization, you can confidently create dynamic and responsive tables using Ant Design Pro.