javascript - 访问并显示位于另一个组件中的模式

Question

我有一个PersonList组件，无论用户点击List.Item我想传递一些详细信息，例如 personId至PersonModal并显示它。我正在使用 Ant Design 组件来实现模态。

以下是我尝试过的方法，但不幸的是我收到了如下错误:

Warning: Can't call setState on a component that is not yet mounted. This is a no-op, but it might indicate a bug in your application. Instead, assign to this.state directly or define a state = {}; class property with the desired state in the PersonModal component.

PersonModal.js

import React from "react";
import {Modal} from "antd";

class PersonModal extends React.Component {
    constructor(props) {
        super(props);
        console.log(this.props.personId)
    }

    state = { visible: false };

    showModal = () => {
        this.setState({
            visible: true,
        });
    };

    // handleOk (...)
    // handleCancel (...)

    render() {
        return <Modal
            title="Basic Modal"
            visible={this.state.visible}
            onOk={this.handleOk}
            onCancel={this.handleCancel}
        >
            Modal body
        </Modal>
    }
}
export default PersonModal;

PersonList.js

import React from "react";
import {Icon, Input, List, Avatar} from "antd";
import PersonModal from "PersonModal/PersonModal"

class PersonList extends React.Component {

    showModal(personId) {
        const modal = new PersonModal({personId: 123})
        modal.showModal()
    }

    render() {
        const persons = this.props.list;
        return (
            <div>
            <List
                itemLayout="horizontal"
                dataSource={persons}
                renderItem={item => (
                    <>
                    <List.Item onClick={this.showModal(123)} style={{cursor: 'pointer'}}>
                        <List.Item.Meta
                            avatar={<Avatar src="avatar.png"/>}
                            title={<span>{item.firstName} {item.lastName}</span>}
                            description={<span>{item.city}, {item.country}</span>}
                        />
                    </List.Item>
                    </>
                )}
            />
            </div>
        );
    }
}

解决这个问题的正确方法是什么？由于我是 React 新手，我认为这不是正确的方法。

在 stackblitz here 上重现了问题

Answer 1

您需要跟踪 PersonList 组件中 PersonModal 的可见状态。您应该有一个 bool 变量来控制 PersonModal 的可见性。

并且PersonModal不会控制其可见性状态，而是从其客户端获取它，在您的情况下，客户端是PersonList。所以让我们从代码开始

首先，编辑 PersonModal 组件以期望来自其客户端的 props

class PersonModal extends React.Component {
    // handleOk (...)
    // handleCancel (...)

    handleCancel = () => {

        // because the client controls the visivlity state of the component
        this.props.hideModal();
    }

    render() {
         /// this.props.isVisible is required, and it will be a boolean true or false.
        const shouldBeVisible = this.props.isVisible;

        return <Modal
            title="Basic Modal"
            visible={shouldBeVisible}
            onOk={this.handleOk}
            onCancel={this.handleCancel}
        >
            Modal body
        </Modal>
    }
}
export default PersonModal;

所以现在你的 PersonModal 组件 expexts 一个 prop；这是 isVisible 属性。

class PersonList extends React.Component {

    state = {
        // the client controls the visibility of the modal with this state key;
        showModal: false,
        personId: null
    }


    // edited
    showModal = (personId) => {
       // set state to update the UI and show the PersonModal
        this.setState({
            showModal: true,
            personId: personId
        });
    }

     hideModal= () => this.setState({showModal: false});

    render() {
        const persons = this.props.list;
        return (
            <div>
             // now PersonModal will only be visible when the parent of it tells it to
            <PersonModal 
            isVisible = {this.state.showModal} 
                hideModal= {this.hideModal}
/>   
            <List
                itemLayout="horizontal"
                dataSource={persons}
                renderItem={item => (
                    <>
                    <List.Item onClick={() => this.showModal(123)} style={{cursor: 'pointer'}}>
                        <List.Item.Meta
                            avatar={<Avatar src="avatar.png"/>}
                            title={<span>{item.firstName} {item.lastName}</span>}
                            description={<span>{item.city}, {item.country}</span>}
                        />
                    </List.Item>
                    </>
                )}
            />
            </div>
        );
    }
}

希望对您有帮助；

这就是 React 世界中解决问题的方式