title: how to get selected value onChange of react redux-form drop down
body: <p>I am using react redux form Fields and I have drop down of classes. I am able to select any class from drop down.
  but the issue is that whenever I select any value (class) from drop down I want to trigger action onChange. When I trigger action with on change drop down values does not set and it does not show selected value.
  I am using following lines of code</p>
  
  <pre><code>&lt;Field name="class._id" component="select" className="form-control" onChange={this.onChange.bind(this)} &gt;
                &lt;option value=""&gt;Select class...&lt;/option&gt;
                {this.props.classes.map(Class =&gt;
                &lt;option value={Class._id} key={Class._id} &gt;{Class.name}&lt;/option&gt;)}
  &lt;/Field&gt;
  </code></pre>
  
  <p>here is onChange function </p>
  
  <pre><code> onChange(){
       console.log(" Triggered")
    }
  </code></pre>
  
  <p>If I do not set onChange event my drop down works correctly and it shows selected value correctly with proper text.
  but I want to call function whenever use select any value</p>