title: Dojo validation that depends on another widget value
body: <p>I have a widget with validation params such as "min" and "max". I want "min" to be set dynamically, because it depends on value contained in another widget.</p>
  
  <pre><code>&lt;input id="test" type="text"
      data-dojo-type="dijit/form/NumberTextBox"
      name= "elevation"
      required="true"
      value="3000"
      data-dojo-props="constraints:{min:-20000,max:20000,places:0},
      invalidMessage:'Invalid elevation.'" /&gt;
  </code></pre>
  
  <p>How can I do something like min: testWidget.getValue()</p>
  
  <p>Thanks.</p>