我正在使用 React JS 构建菜单栏。单击菜单项时,应打开相应的 megamenu。在 megamenu 外部单击时,它应该自行关闭。我通过切换 megamenu 的状态来弥补这一点。但我也想在第二次单击菜单项时关闭 megamenu(即通过单击菜单项切换关闭和打开 megamenu)。我被困在这里,第二次单击菜单项时,状态没有切换回来。
class Menubar extends React.Component {
constructor() {
super();
this.state = {
clicked: false
};
this.handleClick = this.handleClick.bind(this);
this.handleOutsideClick = this.handleOutsideClick.bind(this);
}
componentWillMount() {
document.addEventListener('click', this.handleOutsideClick, false);
}
componentWillUnmount(){
document.removeEventListener('click', this.handleOutsideClick, false);
}
handleClick() {
this.setState({clicked: !this.state.clicked});
}
handleOutsideClick(){
if (this.refs.megaMenu.contains(event.target)) {
} else {
this.setState({
clicked: false
});
}
}
render() {
return (
<div className="container">
<div className="menu-bar">
{/* Menu*/}
<div className="menu-bar-item">
<a className="menu-bar-link" href="#" onClick={this.handleClick}>Points</a>
<div className={"mega-menu"+" "+this.state.clicked} ref="megaMenu">
<div className="mega-menu-content">
<p>Points Menu</p>
</div>
</div>
</div>
</div>
</div>
);
}
}
ReactDOM.render(
<Menubar />,
document.getElementById('example')
);
最佳答案
你需要移动 ref="megaMenu"
以便它也包含按钮,否则当你点击按钮时 handleOutsideClick
也会被触发并且你翻转 this .state.clicked
两次。此外,您忘记在 handleOutsideClick
处理程序中传递 event
。
class Menubar extends React.Component {
constructor() {
super();
this.state = {
clicked: false
};
this.handleClick = this.handleClick.bind(this);
this.handleOutsideClick = this.handleOutsideClick.bind(this);
}
componentWillMount() {
document.addEventListener('click', this.handleOutsideClick, false);
}
componentWillUnmount() {
document.removeEventListener('click', this.handleOutsideClick, false);
}
handleClick() {
this.setState({clicked: !this.state.clicked});
}
handleOutsideClick(event) {
if (!this.menu.contains(event.target)) {
this.setState({
clicked: false
});
}
}
render() {
return (
<div className="container">
<div className="menu-bar">
{/* Menu*/}
<div className="menu-bar-item" ref={el => this.menu = el}>
<a className="menu-bar-link" href="#" onClick={this.handleClick}>Points</a>
<div className={"mega-menu" + " " + this.state.clicked}>
<div className="mega-menu-content">
<p>Points Menu</p>
</div>
</div>
</div>
</div>
</div>
);
}
}
ReactDOM.render(
<Menubar />,
document.getElementById('example')
);
我已经修复了你的 Codepen Demo
此外,考虑使用回调引用,如 ref={el => this.menu = el}
这是一种更好的方法。
关于javascript - React onClick 状态不会切换回来,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38992352/