只有facebook，twitter，sms才能分享Android(share only by facebook, twitter, sms Android)

 这实际上与`per-say的反应毫无关系。 
 
 我已经更改了使用组件state example ，这意味着只要状态发生更改， ValidatedInput就会重新呈现。 如果在渲染组件时example.has_a_promotion正确，则实际上可能不需要这样做。 所以请相应更改。 
 
 disabled实际上只是传递给ValidatedInput组件的属性。 这意味着它的值就像任何其他js一样，当它用{}包裹时运行...所以一个简单的if语句就可以了。 
 
 render(){
  return(    
     <ValidatedInput
       className='product-dropdown'
       onChange={this.onProductChange.bind(this)}
       defaultValue={example.product_id}
       componentClass='select'
       name='product_id'
       placeholder='select'
       disabled={this.state.example.has_a_promotion === true ? true : false}
      />
   );
 }

This actually has nothing to do with react `per-say. 
 
I have changed example to use the components state this will mean the ValidatedInput will re-render whenever the state is changed. This might not actually be necessary if example.has_a_promotion is correct when the component is rendered. So please change accordingly.
 
disabled is actually just a property that is passed down to the ValidatedInput component. Which means its value is just like any other js that is run when its wrapped with {}... so a simple if statement will do the trick.
 
 render(){
  return(    
     <ValidatedInput
       className='product-dropdown'
       onChange={this.onProductChange.bind(this)}
       defaultValue={example.product_id}
       componentClass='select'
       name='product_id'
       placeholder='select'
       disabled={this.state.example.has_a_promotion === true ? true : false}
      />
   );
 }