反作用dnd坎德罗普道具不转真但isover工作正常

我的reactjs演示项目中有3个组件,我正在使用react DnD 组件。

反应 DnD Examples 在这里.

BX.JS

import React, { Component } from 'react';
import { DropTarget } from 'react-dnd';


const boxTarget = {
    canDrop(props) {
        // alert()
    },

    drop(props) {
        // alert()
    }
};

function collect(connect, monitor) {
    return {
      connectDropTarget: connect.dropTarget(),
      isOver: monitor.isOver(),
      canDrop: monitor.canDrop()
    };
}

const ItemTypes = {
    CARD: 'card'
};


class Box extends Component {

    render() {
        const { connectDropTarget, isOver, canDrop } = this.props;

        return connectDropTarget(
          <div style={{
            position: 'relative',
            width: '200px',
            height: '200px',
            background: isOver ? '#ff0000' : '#eee'
          }}>
              { this.props.children }
          </div>
        );
    }

}

export default DropTarget(ItemTypes.CARD, boxTarget, collect)(Box);

J.J.

import React, { Component } from 'react';
import { DragSource } from 'react-dnd';


const ItemTypes = {
    CARD: 'card'
};

const cardSource = {
    beginDrag(props) {
      return {  };
    },

    endDrag(props, monitor) {
      const item = monitor.getItem()
      const dropResult = monitor.getDropResult()

      if (dropResult) {
        alert(`You dropped ${item.name} into ${dropResult.name}!`)
      }
    },
}

function collect(connect, monitor) {
    return {
       connectDragSource : connect.dragSource(),
       connectDragPreview: connect.dragPreview(),
       isDragging : monitor.isDragging()
    } 
}

class Card extends Component {

    render() {
        const { connectDragSource , isDragging } = this.props;

        return connectDragSource( 
          <div style={{
            opacity : isDragging ? 0.5 : 1,
            height: '50px',
            width: '50px',
            backgroundColor: 'orange',
          }}>
            &#9822;
          </div>
        );
      }

}

export default DragSource(ItemTypes.CARD, cardSource , collect)(Card);

simpledrag.js公司

import React, { Component } from 'react';

import { DragDropContext } from 'react-dnd';
import HTML5Backend from 'react-dnd-html5-backend';
import CARD from './card';
import BOX from './box';
import Calder from './fullcalender';

class simpleDrag extends Component {

    render() {
        return(
            <div>
                <BOX />
                <CARD/>
            </div>    
        ); 
    }

} 

export default DragDropContext(HTML5Backend)(simpleDrag);

simpleDrag.js 是同时显示box和card组件的父组件,现在我面临的问题是box.js我有以下三元样式检查:

background: isOver ? '#ff0000' : '#eee'

现在 isOver 这个样式起作用了,就是div变成了“ff0000”,但是这个检查不起作用 canDrop ,为什么 烛光 检查不工作?

上面的代码可以在我的github repo中找到 HERE .