Correctly creating an antd Form using the extends React.Component mechanism

Question

I am trying to reproduce the antd Form example in https://github.com/ant-design/ant-design/blob/master/components/form/demo/horizontal-login.md

Replacing React.createClass with extends React.Component but I am getting a Uncaught TypeError: Cannot read property 'getFieldDecorator' of undefined

with the following code:

import { Form, Icon, Input, Button } from 'antd';
const FormItem = Form.Item;

export default class HorizontalLoginForm extends React.Component {
    constructor(props) {
        super(props);
    }

  handleSubmit(e) {
    e.preventDefault();
    this.props.form.validateFields((err, values) => {
      if (!err) {
        console.log('Received values of form: ', values);
      }
    });
  },
  render() {
    const { getFieldDecorator } = this.props.form;
    return (
      <Form inline onSubmit={this.handleSubmit}>
        <FormItem>
          {getFieldDecorator('userName', {
            rules: [{ required: true, message: 'Please input your username!' }],
          })(
            <Input addonBefore={<Icon type="user" />} placeholder="Username" />
          )}
        </FormItem>
        <FormItem>
          {getFieldDecorator('password', {
            rules: [{ required: true, message: 'Please input your Password!' }],
          })(
            <Input addonBefore={<Icon type="lock" />} type="password" placeholder="Password" />
          )}
        </FormItem>
        <FormItem>
          <Button type="primary" htmlType="submit">Log in</Button>
        </FormItem>
      </Form>
        )
    }
}

Looks like the missing Form.create part is causing the issue, but don't know where it fits using the extends mechanism.

How can I properly do it ?

Answer 1

@vladimirimp is on the right track, but there are 2 issues with the chosen answer.

1. Higher-Order Components (such as Form.create()) should not be called in the render method.
2. JSX requires user-defined component names (such as myHorizontalLoginForm) to start with capital letters.

To fix this, we just need to change our default export of HorizontalLoginForm:

class HorizontalLoginForm extends React.Component { /* ... */ }

export default Form.create()(HorizontalLoginForm);

Then we can use HorizontalLoginForm directly without needing to set it to a new variable. (but if you did set it to a new variable, you would want to name that variable MyHorizontalLoginForm or anything else that starts with a capital letter).

Answer 2

When you wish to include your form class in parent component you must first create form, for example in parent components render method:

    ...

    render() {
        ...

        const myHorizontalLoginForm = Form.create()(HorizontalLoginForm);
        ...
          return (
          ...
          <myHorizontalLoginForm />
          )
    }

Be sure to import your HorizontalLoginForm class in the parent class.