src/Select.jsx

   1 import React, { PropTypes } from 'react';
   2 import ReactDom from 'react-dom';
   3 import classnames from 'classnames';
   4
   5 const scrollTo = (element, to, duration) => {
   6   const requestAnimationFrame = window.requestAnimationFrame ||
   7     function requestAnimationFrameTimeout() {
   8       return setTimeout(arguments[0], 10);
   9     };
  10   // jump to target if duration zero
  11   if (duration <= 0) {
  12     element.scrollTop = to;
  13     return;
  14   }
  15   const difference = to - element.scrollTop;
  16   const perTick = difference / duration * 10;
  17
  18   requestAnimationFrame(() => {
  19     element.scrollTop = element.scrollTop + perTick;
  20     if (element.scrollTop === to) return;
  21     scrollTo(element, to, duration - 10);
  22   });
  23 };
  24
  25 const Select = React.createClass({
  26   propTypes: {
  27     prefixCls: PropTypes.string,
  28     options: PropTypes.array,
  29     selectedIndex: PropTypes.number,
  30     type: PropTypes.string,
  31     onSelect: PropTypes.func,
  32     onMouseEnter: PropTypes.func,
  33   },
  34
  35   componentDidMount() {
  36     // jump to selected option
  37     this.scrollToSelected(0);
  38   },
  39
  40   componentDidUpdate(prevProps) {
  41     // smooth scroll to selected option
  42     if (prevProps.selectedIndex !== this.props.selectedIndex) {
  43       this.scrollToSelected(120);
  44     }
  45   },
  46
  47   onSelect(value) {
  48     const { onSelect, type } = this.props;
  49     onSelect(type, value);
  50   },
  51
  52   getOptions() {
  53     const { options, selectedIndex, prefixCls } = this.props;
  54     return options.map((item, index) => {
  55       const cls = classnames({
  56         [`${prefixCls}-select-option-selected`]: selectedIndex === index,
  57         [`${prefixCls}-select-option-disabled`]: item.disabled,
  58       });
  59       let onclick = null;
  60       if (!item.disabled) {
  61         onclick = this.onSelect.bind(this, +item.value);
  62       }
  63       return (<li
  64         className={cls}
  65         key={index}
  66         onClick={onclick}
  67         disabled={item.disabled}
  68       >
  69         {item.value}
  70       </li>);
  71     });
  72   },
  73
  74   scrollToSelected(duration) {
  75     // move to selected item
  76     const select = ReactDom.findDOMNode(this);
  77     const list = ReactDom.findDOMNode(this.refs.list);
  78     let index = this.props.selectedIndex;
  79     if (index < 0) {
  80       index = 0;
  81     }
  82     const topOption = list.children[index];
  83     const to = topOption.offsetTop;
  84     scrollTo(select, to, duration);
  85   },
  86
  87   render() {
  88     if (this.props.options.length === 0) {
  89       return null;
  90     }
  91
  92     const { prefixCls } = this.props;
  93
  94     return (
  95       <div
  96         className={`${prefixCls}-select`}
  97         onMouseEnter={this.props.onMouseEnter}
  98       >
  99         <ul ref="list">{this.getOptions()}</ul>
 100       </div>
 101     );
 102   },
 103 });
 104
 105 export default Select;