title: Custom validation of dijit textboxes
body: <p>I was today seeking the net for information about textbox-validation, but even on Dojo-Homepage I couldn't get any useful information.</p>
  
  <p>My problem: I've got a NumberSpinner, in which only numbers in steps of ten (10, 20, 30, ...) should be allowed. But I've got no idea how to set a validator for this. In the 'constraints'-statement there seems to be no possibility to do this. And I don't know how to use the validator-function so that the box shows me warning sign immediately when typing in somethin wrong.</p>
  
  <p>Another question is how to check if any part of a form is not valid before sending it. Is there an attribute in every input/select-box like 'valid' to check them all at once?</p>
  
  <p>Oh, one hint, I create all widgets programmatically.</p>
  
  <p>Hopefully anyone out there can help me!!!</p>
  
  <p>Best regards, 
  Robin</p>