在本章中,我們將學(xué)習(xí)React如何使用動(dòng)畫元素。
這是React插件,用于創(chuàng)建基本的CSS轉(zhuǎn)換和動(dòng)畫。從命令提示符窗口中安裝它 -
F:\worksp\reactjs\reactApp> npm install react-addons-css-transition-group
在項(xiàng)目根目錄里面創(chuàng)建一個(gè)新的文件夾:css,并在文件夾中創(chuàng)建一個(gè)文件:style.css 。 為了能夠在應(yīng)用程序中使用它,需要將它添加到index.html中的head元素中。如下文件(index.html)代碼所示 -
<!DOCTYPE html>
<html lang = "en">
<head>
<meta charset = "UTF-8">
<title>React動(dòng)畫示例</title>
<link rel = "stylesheet" type = "text/css" href = "css/style.css">
</head>
<body>
<div id = "app"></div>
<script type = "text/javascript" src = "index.js"></script>
</body>
</html>
創(chuàng)建一個(gè)基本的React組件。 ReactCSSTransitionGroup元素將被用作想要?jiǎng)赢嫷慕M件的包裝。它將使用transitionAppear和transitionAppearTimeout,而transitionEnter和transitionLeave是false。
文件:App.jsx -
import React from 'react';
var ReactCSSTransitionGroup = require('react-addons-css-transition-group');
class App extends React.Component {
render() {
return (
<div>
<ReactCSSTransitionGroup transitionName = "example"
transitionAppear = {true} transitionAppearTimeout = {500}
transitionEnter = {false} transitionLeave = {false}>
<h1>My Element...</h1>
</ReactCSSTransitionGroup>
</div>
);
}
}
export default App;
文件:main.js -
import React from 'react'
import ReactDOM from 'react-dom';
import App from './App.jsx';
ReactDOM.render(<App />, document.getElementById('app'));
CSS動(dòng)畫非常簡(jiǎn)單。文件:css/style.css -
.example-appear {
opacity: 0.01;
}
.example-appear.example-appear-active {
opacity: 1;
transition: opacity 500ms ease-in;
}
當(dāng)啟動(dòng)應(yīng)用程序,元素將淡入。
當(dāng)想要添加或刪除列表中的元素時(shí),可以使用輸入和離開動(dòng)畫。
文件:App.jsx -
import React from 'react';
var ReactCSSTransitionGroup = require('react-addons-css-transition-group');
class App extends React.Component {
constructor(props) {
super(props);
this.state = {
items: ['Item 1...', 'Item 2...', 'Item 3...', 'Item 4...']
}
this.handleAdd = this.handleAdd.bind(this);
};
handleAdd() {
var newItems = this.state.items.concat([prompt('Create New Item')]);
this.setState({items: newItems});
}
handleRemove(i) {
var newItems = this.state.items.slice();
newItems.splice(i, 1);
this.setState({items: newItems});
}
render() {
var items = this.state.items.map(function(item, i) {
return (
<div key = {item} onClick = {this.handleRemove.bind(this, i)}>
{item}
</div>
);
}.bind(this));
return (
<div>
<button onClick = {this.handleAdd}>Add Item</button>
<ReactCSSTransitionGroup transitionName = "example"
transitionEnterTimeout = {500} transitionLeaveTimeout = {500}>
{items}
</ReactCSSTransitionGroup>
</div>
);
}
}
export default App;
文件:main.js -
import React from 'react'
import ReactDOM from 'react-dom';
import App from './App.jsx';
ReactDOM.render(<App />, document.getElementById('app'));
文件:css/style.css -
.example-enter {
opacity: 0.01;
}
.example-enter.example-enter-active {
opacity: 1;
transition: opacity 500ms ease-in;
}
.example-leave {
opacity: 1;
}
.example-leave.example-leave-active {
opacity: 0.01;
transition: opacity 500ms ease-in;
}
當(dāng)啟動(dòng)應(yīng)用程序,然后點(diǎn)擊添加項(xiàng)目按鈕,會(huì)出現(xiàn)提示。
當(dāng)點(diǎn)擊"Add Item..."并輸入名稱,然后按確定,新的元素將淡入。

現(xiàn)在可以通過(guò)點(diǎn)擊刪除一些項(xiàng)目(例如:Item 3 … )。 該項(xiàng)目將從列表中淡出。