title: add/remove elements to array with checkboks and reactjs
body: <p>I have this code that inserts the ids of the checkboks into an array, but if I disable them, it does not remove them, i use update to react-addons-update
  any suggestions</p>
  
  <pre><code>     constructor(props) {
          super(props);
           this.state={
             keyGen:[]
           }
        }
        render(){  
           &lt;form&gt; 
              {this.renderElements()}
               &lt;input type="submit" value="Save" /&gt;
          &lt;/form&gt;
        renderElement(){
         return this.props.Elements.map((item, index)=&gt;{
  render(
          &lt;Input name='list' type='checkbox' onClick={()=&gt;this.updateStateList(item.id)} label='Add' className='listTour' /&gt;
         ) 
          })
          }
  
        updateStateList(value){
          this.setState(update(this.state, {keyGen: {$push:[value]}}))
          console.log(this.state.keyGen)
        }
  </code></pre>
  
  <p>thanks</p>