模态没有出现在反应中

Question

I'm new to react thus the question. This is my CustomModal,

import React from 'react';
import {useState} from "react";
import {Button, Modal} from "react-bootstrap";

const CustomModal = (props) =>{
    const [show, setShow] = useState(true);
    const handleClose = () => setShow(false);

    return (
        <div>
            <Modal show={show} animation={false}>
                <Modal.Header closeButton>
                    <Modal.Title>Modal heading</Modal.Title>
                </Modal.Header>
                <Modal.Body>{props.message}</Modal.Body>
                <Modal.Footer>
                    <Button variant="secondary" onClick={handleClose}>
                        Close
                    </Button>
                </Modal.Footer>
            </Modal>
        </div>
    )
};
export default CustomModal;

I want to render it inside a class component when user submits a registration form.

class Register extends React.Component {
    state = {
        email : '',
        username: '',
        password: '',
        second_password: ''
    };
    handleSubmit = async (event) =>{
        event.preventDefault();

        const emailValidated = await this.validateEmail(this.state.email);
        const usernameValidated = this.validateUsername(this.state.username);
        const passwordValidated = this.validatePassword(this.state.password, this.state.second_password);
        let registrationComplete = false;
        if(emailValidated === true && usernameValidated === true && passwordValidated === true){
            registrationComplete = await this.register(this.state.email, this.state.username, this.state.password);
            console.log(registrationComplete);
            this.showModal("Hello World!"); //This is the function begin called to show the modal.
        }

    };
    validateUsername = (username) =>{
        return true;
    };

    validatePassword = (password, second) =>{
        return true;
    };

    validateEmail = async (email) =>{
        return true;
    };


    //This is the function that should display the modal

    showModal = (message) =>{
        return (<CustomModal message={message}/>);
    };


    register = async (email, username, password) =>{
        return true;
    };
    render() {
        return (
            <div className="register">
                <h1>Register</h1>
                <Form onSubmit={this.handleSubmit}>
                    <Form.Group controlId="formBasicEmail">
                        <Form.Label>Email address</Form.Label>
                        <Form.Control type="email"
                                      placeholder="Enter email"
                                      value={this.state.email}
                                      onChange={event => this.setState({email: event.target.value})}/>
                        <Form.Text className="text-muted">
                            Please make sure you've access to this mail. You'll receive an activation code here.
                        </Form.Text>
                    </Form.Group>

                    <Form.Group controlId="formPlainText">
                        <Form.Label className="form-label">Username</Form.Label>
                        <Form.Control type="text"
                                      placeholder="Username"
                                      value={this.state.username}
                                      onChange={event => this.setState({username: event.target.value})}/>
                        <Form.Text className="text-muted">
                            Please make it atleast 8 characters long.
                        </Form.Text>
                    </Form.Group>

                    <Form.Group controlId="formBasicPassword">
                        <Form.Label>Password</Form.Label>
                        <Form.Control type="password"
                                      placeholder="Password"
                                      value={this.state.password}
                                      onChange={event => this.setState({password: event.target.value})}/>
                        <Form.Text className="text-muted">
                            Please make sure it's atleast 8 characters long and uses a mix of letters and numbers.
                        </Form.Text>
                    </Form.Group>

                    <Form.Group controlId="formBasicPassword">
                        <Form.Label>Retype Password</Form.Label>
                        <Form.Control type="password"
                                      placeholder="Password"
                                      value={this.state.second_password}
                                      onChange={event => this.setState({second_password: event.target.value})}/>
                    </Form.Group>


                    <Button variant="primary" type="submit">
                        Register
                    </Button>
                </Form>
            </div>
        );
    }
}
export default Register;

All the values are correct and the console log shows true but the Modal doesn't display. Can someone help me with this?

Answer 1

There are some issues on your code

1. The customModal has to be part of the render of the Register component
2. There should be a state to track the status of the modal from the Register component
3. Also the register has to be notified when the Modal closes

I have modified your code and working. You can find it live here

Answer 2

I prefer attack this problem creating portals here documentation .

you might to have issues with z-index in the future.

Basically, you create an element outside the DOM hierarchy.

Now, your issue is that, you must render modal inside render method and control it, with boolean state "showModal".

I prepare for you an example:

example in my GitHub account

• git clone ...
• npm install
• npm run start

preview: