Babylon.js/sharedUiComponents/lines/lineContainerComponent.tsx

import * as React from "react";
import { DataStorage } from 'babylonjs/Misc/dataStorage';
const downArrow = require("./downArrow.svg");

interface ILineContainerComponentProps {
    title: string;
    children: any[] | any;
    closed?: boolean;
}

export class LineContainerComponent extends React.Component<ILineContainerComponentProps, { isExpanded: boolean }> {
    constructor(props: ILineContainerComponentProps) {
        super(props);

        let initialState = DataStorage.ReadBoolean(this.props.title, !this.props.closed);

        this.state = { isExpanded: initialState };
    }

    switchExpandedState(): void {
        const newState = !this.state.isExpanded;

        DataStorage.WriteBoolean(this.props.title, newState);

        this.setState({ isExpanded: newState });
    }

    renderHeader() {
        const className = this.state.isExpanded ? "collapse" : "collapse closed";

        return (
            <div className="header" onClick={() => this.switchExpandedState()}>
                <div className="title">
                    {this.props.title}
                </div>
                <div className={className}>
                    <img className="img" title={this.props.title} src={downArrow}/>
                </div>
            </div>
        );
    }

    render() {
        if (!this.state.isExpanded) {
            return (
                <div className="paneContainer">
                    <div className="paneContainer-content">
                        {
                            this.renderHeader()
                        }
                    </div>
                </div>
            );
        }

        return (
            <div className="paneContainer">
                <div className="paneContainer-content">
                    {
                        this.renderHeader()
                    }
                    <div className="paneList">
                        {this.props.children}
                    </div >
                </div>
            </div>
        );
    }
}