Custom fields

In Kottster, all fields are basically table columns. If you need to add or modify fields in the table pages, you can do so by modifying or adding custom columns.

Add new fields to the form

If you want to display a new field in the form, you can use the customColumns prop. This is useful for adding additional fields without modifying the existing columns or backend logic.

Add the customColumns prop to the TablePage component. This prop accepts an array of objects, each representing a custom column.

Example of a page with a custom field:

app/pages/users/index.jsx

import { TablePage } from '@kottster/react';

export default () => (
  <TablePage
    customColumns={[
      // Add a custom column to the table
      {
        // The unique key for the new column
        column: 'fullName',

        // The display label for the column
        label: 'Full name',

        // Position of the column, if not specified, it will be added to the end
        formFieldPosition: 1,

        // Hide the column in the table view since it's only for the form
        hiddenInTable: true,

        fieldInput: {
          type: 'custom',

          // Render component function
          renderComponent: ({ record }) => {
            return (
              <input 
                type='text'
                placeholder='Enter full name'
                value={`${record.first_name || ''} ${record.last_name || ''}`}
                onChange={(e) => {
                  const values = e.target.value.split(' ');

                  updateFieldValue('first_name', values[0] || '');
                  updateFieldValue('last_name', values[1] || '');
                }}
              />
            )
          },
        },
      },
    ]}
  />
);

Modify field input for existing columns

If you want to update existing fields (columns), you can use the columnOverrides prop. This is useful for adding custom render for field inputs.

Add the columnOverrides prop to the TablePage component. This prop accepts an object where each key is the column name and the value is a function that takes the existing column configuration and returns the modified column configuration.

Example of modifying email field:

app/pages/users/index.jsx

import { TablePage } from '@kottster/react';

export default () => (
  <TablePage
    columnOverrides={{
      // Modifying the field input of the email column
      email: column => ({
        ...column,

        // The custom display label for the column
        label: 'Email address',

        // The custom field input
        fieldInput: {
          type: 'custom',
          renderComponent: (params) => {
            const { value, updateFieldValue } = params;

            return (
              <input 
                type='email'
                placeholder='Enter email'
                value={value} 
                onChange={(e) => updateFieldValue('email', e.target.value)} 
              />
            )
          },
        }
      }),
    }}
  />
);

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Learn more about fieldInput and its parameters in the API reference.