Thursday, September 30, 2010

ADF 11g inputNumberSpinbox: Changing Value When Value is Null

This post is a short one, however, it is useful. When you use a Spinbox to change and display values, you might encounter a problem when the Spinbox' value is empty (or Null).

I used the Employees table in the HR Schema for this example.
Created ADF BC for this, and dropped the collection as an ADF Form an a simple page.
I converted the commission inputText component to an inputNumberSpinbox and set stepSize="0.1".

You can click whatever you want but the Spinbox just doesn't work for NULL values.




One of the options you have, is to enter a value in the Spinbox by just typing it.

A somewhat more elegant solution is the use of javascript.
For this I add a client Listener to the Spinbox.



The clientListener invokes a javascript function as soon as the Spinbox gets focus. Whenever the value is NULL, it will set the value to ZERO. The Spinbox now knows what to do.

   <af:document id="d1">  
<af:resource type="javascript">
function initSpinner(evt){
spinbox = evt.getSource();
val = spinbox.getValue();
if (val ==null){
spinbox.setValue(0);
}
}
</af:resource>


When you click the empty Spinbox now, it will work as expected.