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BigDecimal conversion back to presentation weird

Francisco Serrano
6 years ago Jan 25, 2016 5:32pm
Dennis Wightman
6 years ago Jan 27, 2016 4:35am

That's quite an issue.  Out of curiousity I tried out some code and could not duplicate what you're seeing.  The only way I can get that something like that to happen is like this:

tf.addValueChangeListener(new Property.ValueChangeListener()
private static final long serialVersionUID = -6549081726526133772L;
public void valueChange(Property.ValueChangeEvent event)
String value = (String) event.getProperty().getValue();
System.out.println(">>>>value: "+value);
BigDecimal bd = new BigDecimal(value);
BigDecimal ten = new BigDecimal("10");
bd = bd.divide(ten,3, BigDecimal.ROUND_HALF_UP);
System.out.println(">>>>result: "+bd);
// method to set the text field value:
setTfValue("" + bd);

Here's what I get in the system log (and get 0.0000 in the text field):

>>>>value: 234.56789
>>>>result: 23.457
>>>>value: 23.457
>>>>result: 2.346
>>>>value: 2.346
>>>>result: 0.235
>>>>value: 0.235
>>>>result: 0.024
>>>>value: 0.024
>>>>result: 0.002
>>>>value: 0.002
>>>>result: 0.000
>>>>value: 0.000
>>>>result: 0.000

So it looks like there's a 'feedback loop' where the TextField keeps feeding the value in, and the processing keeps happening.  This is a contrived example where processing logic is taking place inside the event handler, but maybe something along these lines could be happening?

It does occur to me that changing a TextField dynamically is a little risky.  Might it not be more appropriate to try displaying the computed value in a different place like a Label?  At the very least, try temporarily setting the result in a label, and take away the code that's putting it in the TextField and see if the correct result comes back.


Francisco Serrano
6 years ago Jan 27, 2016 7:52am
Dennis Wightman
6 years ago Jan 27, 2016 4:04pm