javascript - 使用 React.js 的 SlideUp() 和 SlideDown() 动画

Question

我创建了一个由slideUp()和slideDown()动画组成的react组件。我已经使用 jQuery Slideup 和 Slidedown 方法实现了。

我必须使用 react 动画来实现此功能。

我读到了ReactTransitionGroup和ReactCSSTransitionGroup。解释的方式告诉我，我们可以在 DomNode 安装到组件或卸载时执行此功能(如果我错了，请纠正我)。

我的问题是 --> 如何以 React 方式而不使用 jQuery 执行 Slideup() 和 Slidedown()。

请参阅此 jsFiddle https://jsfiddle.net/guc3yrm1/

P.S ->请解释一下为什么这个 react 动画部分与 jQuery 相比似乎有点困难(我是一个 jQuery 人)

var Hello = React.createClass({
    getInitialState: function() {
        return {
            slide: false,
        }
    },
    slide: function() {
        if (this.state.slide) {
            $(this.refs.slide).slideDown();
            this.setState({
                slide: false
            });
        } else {
            $(this.refs.slide).slideUp();
            this.setState({
                slide: true
            });
        }
    },
    render: function() {
        return ( 
            <div>
                <input type = "button" value = "clickme" onClick = {this.slide}/> 
                <br />
                <br />
                <div className = "slide" ref="slide" >< /div>
            </div>
        );
    }
});

ReactDOM.render( < Hello name = "World" / > ,
    document.getElementById('container')
);

Answer 1

您可以在这两个动画的 API 中实现动画。主要区别如下:

ReactTransitionGroup is the API upon which ReactCSSTransitionGroup is built. The main difference between the two is that ReactTransitionGroup animations are written in Javascript instead of CSS, and a callback is provided to be invoked when animations are complete instead of relying on CSS transition events.

我的结论是使用 CSS 动画来完成简单的任务，而使用 Javascript 来完成复杂的任务。

例如，如果组件具有静态高度 - 您可以通过 CSS 实现它，如下例所示。但如果宽度/高度是动态的，那么你可以使用 Javascript 来实现。在 Javascript 示例中，我使用 Velocity 库来制作动画。 It's performance better than jQuery's animations 。当然你可以自己实现动画，但为什么要重新发明轮子呢？

我已经使用这两个 API 实现了 SlideUp/slideDown。看看下面的内容。

(CSS) 通过 ReactCSSTransitionGroup 实现:

const CSSTransitionGroup = React.addons.CSSTransitionGroup;
const TransitionGroup = React.addons.TransitionGroup;

class Example extends React.Component{
    constructor(props) {
        super(props);
        this.state = { visible: false };
        this.handleClick = this.handleClick.bind(this)
    }

    handleClick() {
    	this.setState({ visible: ! this.state.visible });
    }

    render() {
        return <div>
            <button onClick={this.handleClick}>{this.state.visible ? 'Slide up' : 'Slide down'}</button>
            <CSSTransitionGroup transitionName="example">
            	{ this.state.visible ? <div className='panel' /> : null }
            </CSSTransitionGroup>
        </div>
    }
}

React.render(<Example />, document.getElementById('container'));

.panel {
    width: 200px;
    height: 100px;
    background: green;
    margin-top: 10px;
}

.example-enter {
    height: 0px;
}

.example-enter.example-enter-active {
    height: 100px;
    -webkit-transition: height .3s ease;
}

.example-leave.example-leave-active {
    height: 0px;
    -webkit-transition: height .3s ease;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.13.1/react-with-addons.js"></script>
<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

JSFiddle - React Slide up and Slide down animation - CSS Transtion Group .

<小时/>

(Javascript)通过ReactTransitionGroup实现:

const TransitionGroup = React.addons.TransitionGroup;

class Example extends React.Component{
    constructor(props) {
        super(props);
        this.state = { visible: false };
        this.handleClick = this.handleClick.bind(this)
    }

    handleClick() {
        this.setState({ visible: ! this.state.visible });
    }

    render() {
        return <div>
            <button onClick={this.handleClick}>{this.state.visible ? 'Slide up' : 'Slide down'}</button>
                <TransitionGroup>
                    { this.state.visible ? <Accordion /> : null }
                </TransitionGroup>
            </div>
        }
    }

    class Accordion extends React.Component {
        componentWillEnter (callback) {
            const element = this.container.getDOMNode();
            Velocity(element, 'slideDown', { duration: 300 }).then(callback);
        }

        componentWillLeave (callback) {
            const element = this.container.getDOMNode();
            Velocity(element, 'slideUp', { duration: 300 }).then(callback);
        }

        setContainer(c) {
            this.container = c;
        }

        render() {
            return <div className="panel" ref={this.setContainer.bind(this)}>
                Lorem Ipsum is simply dummy text of the printing and typesetting industry.
                Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.
            </div>
        }
    }

React.render(<Example />, document.getElementById('container'));

.panel {
    background: green;
    margin-top: 10px;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.13.1/react-with-addons.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/velocity/1.4.3/velocity.min.js"></script>

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

JSFiddle - React Slide up and Slide down animation - Javascript Transition group .

<小时/>

鸣谢:

• Animations with ReactTransitionGroup
• CSS vs. JS Animation: Which is Faster?