ReactJs 切换按钮打开菜单

Question

我构建了一个 React 组件，Toggle Menu，它由按钮触发。首次打开后我无法看到菜单打开/关闭。有点迷失如何开始解决这个问题...这是我用作引用的示例 How to Build a Sliding Menu Using ReactJS

export default class ToggleMenu extends React.Component {

  showRight = () => {
    this.right.show();
  }


  constructor(props) {
    super(props);
    this.showRight = this.showRight.bind(this);
  }

  render() {

    return (
      <div>
        <button onClick={this.showRight}>Show Right Menu!</button>
        <Menu ref={right => this.right = right} alignment="right">
        <MenuItem hash="first-page">First Page</MenuItem>
        <MenuItem hash="second-page">Second Page</MenuItem>
        <MenuItem hash="third-page">Third Page</MenuItem>
      </Menu>
      </div>
    );
  }
}


export default class Menu extends React.Component {
    state = {
      visible: false,
    };

    show() {
      this.setState({ visible: true });
    }

    hide() {
      this.setState({ visible: false });
    }

    render() {
      const { visible } = this.state;

      return (
        <div className="menu">
          {
            visible &&
              <div className={this.props.alignment}>{this.props.children}</div>
          }
        </div>
      );
    }
}

Answer 1

通过将 State 移动到主 ToggleMenu 中，您可以让该组件保持菜单的可见性。

class ToggleMenu extends React.Component {
    constructor(props) {
        super(props);

        this.state = {
            visible: false  
        };

        this.toggleMenu = this.toggleMenu.bind(this);
    }

    toggleMenu() {
        this.setState({visible: !this.state.visible})
    }

    render() {
        return (
            <div>
                <button onClick={this.toggleMenu}>Show Right Menu!</button>
                {this.state.visible && <Menu alignment="right">
                <MenuItem hash="first-page">First Page</MenuItem>
                <MenuItem hash="second-page">Second Page</MenuItem>
                <MenuItem hash="third-page">Third Page</MenuItem>
                </Menu>}
            </div>
        );
    }
}

这使我能够将您的菜单更改为无状态组件:

const Menu = ({alignment, children}) => (
    <div className="menu">
        <div className={alignment}>{children}</div>
    </div>
);

我在这里创建了一个 webpackbin(现在带有动画):https://www.webpackbin.com/bins/-Klh1VM-n4RDCkEbkK67

对于过渡和动画，我建议您查看 https://github.com/reactjs/react-transition-group