React 九宫格拖拽排序

实现的效果:

实现的效果

实现步骤

1、列表设置可拖动 draggable='true'
2、拖拽到某个元素，目标元素放大透明动画
3、记录元素移动索引，索引值不同，则排序。
4、数据排序 - splice() 方法，当前拖拽元素更换为目标元素
5、拖拽完成，当前拖拽元素样式还原

部分代码

css:

ul ,li{
  list-style: none
}
ul{
  width:480px;
}
li{
   display:inline-block;
   width:150px;
   height:150px;
   margin:5px;
   line-height:150px;
   text-align:center;
   font-size:30px;
   transition:all .5s;
   -moz-transition:all .5s;
   -webkit-transition:all .5s; 
   -o-transition:all .5s; 
}

js:

class List extends React.Component {
  constructor(props) {
    super(props);
    this.state = {...props};
  }
  
  handleData(){
    this.dragged.style.opacity = "1";
    this.dragged.style.transform = "scale(1)";
    const from = this.dragged.dataset.id;
    const to = this.target.dataset.id;
    if(from !== to ) {
      var data = this.state.data;
      data.splice(to, 0, data.splice(from, 1)[0]);
      this.setState({data: data});
      this.dragged=this.target;
    }
  }
  dragStart(e) {
    this.dragged = e.target;
  }
  drop(e) {
    e.preventDefault();
    this.dragged.style.opacity = "1";
    this.dragged.style.transform = "scale(1)";
  }
  dragOver(e) {
    e.preventDefault();
  }
  dragEnter(e) {
    e.preventDefault();
    if (e.target.tagName !== "LI") {
       return;
    }
    this.target = e.target;
    this.target.style.opacity = "0.2";
    this.target.style.transform = "scale(1.1)";
    this.handleData();
  }

  render() {
    var listItems = this.state.data.map((item, index) => {
      return (
        <li 
          data-id={index}
          key={index}
          style={{background:item.bgColor}}
          draggable='true'
          onDragEnter={this.dragEnter.bind(this)}
          onDrop={this.drop.bind(this)}
          onDragOver={this.dragOver.bind(this)}
          onDragStart={this.dragStart.bind(this)}
          data-item={JSON.stringify(item)}
        >
          {item.index}
        </li>
      )
     });
    return (
      <ul className ="contain">
        {listItems}
      </ul>
    )
  }
}
class App extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      data: [{
          index: 1,
          bgColor: "red"
        },{
          index: 2,
          bgColor: "green"
        },{
          index: 3,
          bgColor: "blue"
        },{
          index: 4,
          bgColor: "yellow"
        },{
          index: 5,
          bgColor: "orange"
        },{
          index: 6,
          bgColor: "grey"
        },{
          index: 7,
          bgColor: "blueviolet"
        },{
          index: 8,
          bgColor: "bisque"
        },{
          index: 9,
          bgColor: "cyan"
        }]
    }
  }
  render() {
    return (
      <div><List data={this.state.data} /></div>
    )
  }
}

ReactDOM.render(
  <App />,
  document.getElementById('app'),
);

demo地址：https://codepen.io/itguliang-the-selector/pen/jgqVzr

原文地址：https://mp.weixin.qq.com/s/2oZuxH2BXgs8RIe22IZjPQ