React Canvas：高性能渲染 React 组件

var React = require('react');  var ReactCanvas = require('react-canvas');    var Surface = ReactCanvas.Surface;  var Image = ReactCanvas.Image;  var Text = ReactCanvas.Text;    var MyComponent = React.createClass({      render: function () {      var surfaceWidth = window.innerWidth;      var surfaceHeight = window.innerHeight;      var imageStyle = this.getImageStyle();      var textStyle = this.getTextStyle();        return (        <Surface width={surfaceWidth} height={surfaceHeight} left={0} top={0}>          <Image style={imageStyle} src='...' />          <Text style={textStyle}>            Here is some text below an image.          </Text>        </Surface>      );    },      getImageHeight: function () {      return Math.round(window.innerHeight / 2);    },      getImageStyle: function () {      return {        top: 0,        left: 0,        width: window.innerWidth,        height: this.getImageHeight()      };    },      getTextStyle: function () {      return {        top: this.getImageHeight() + 10,        left: 0,        width: window.innerWidth,        height: 20,        lineHeight: 20,        fontSize: 12      };    }    });