old_contents: import React, { Component } from 'react';
  
  module.exports = (_items) => {
      const _ItemList = _items.map((_item, i) => {
      let bgColor   = 'ffffff';
      let randomHex = (Math.random()*0xFFFFFF<<0).toString(16);
      return (
          <div className='col-md-3 col-sm-6' key={i} id={'item-'+i}>
            <div className='thumbnail'>
              <div className='caption'>
                <img src={'http://placehold.it/400/'+bgColor+'/'+randomHex+'?text='+ _item.sku} alt={_item.name} className='img-responsive' />
                <h4>{_item.name}</h4>
                <span>{_item.description}</span>     
                <h5>{'$' + _item.price}</h5>         
                <div className="text-right">
                  <AddToCartButton />
                </div>
              </div>
            </div>
          </div>
        )
      });
      return _ItemList;
  }
  
  class AddToCartButton extends Component {
    render() {
      return (
        <button type='button' className='btn btn-default btn-lg'>
          <i className='fa fa-cart-plus'></i>
        </button>
      );
    }
  }
  
new_contents: import React, { Component } from 'react';
  
  module.exports = (_items) => {
      const _ItemList = _items.map((_item, i) => {
      let bgColor   = 'ffffff';
      let randomHex = (Math.random()*0xFFFFFF<<0).toString(16);
      return (
          <div className='col-md-3 col-sm-6' key={i} id={_item._id}>
            <div className='thumbnail'>
              <div className='caption'>
                <img src={'http://placehold.it/400/'+bgColor+'/'+randomHex+'?text='+ _item.sku} alt={_item.name} className='img-responsive' />
                <h4>{_item.name}</h4>
                <span>{_item.description}</span>     
                <h5>{'$' + _item.price}</h5>         
                <div className="text-right">
                  <AddToCartButton id={_item._id}/>
                </div>
              </div>
            </div>
          </div>
        )
      });
      return _ItemList;
  }
  
  class AddToCartButton extends Component {
    render() {
      return (
        <button onClick={this._addToCartHandler} type='button' className='btn btn-default btn-lg'>
          <i className='fa fa-cart-plus'></i>
        </button>
      );
    }
    _addToCartHandler(){
      let newItem = {
        id: this.props.id,
        qty: this.state.qty
      };
    }
  }
  
subject: add _addToCartHandler