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Re: Field update loop pro

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Stephen wrote:
> I was wondering if anyone can suggest an elegant/simple way to solve this
> problem in my SWT application. Obviously I could use some sort of "brute
> force" method, but I would rather not.
>
> I have a number of Text fields, and they each have a field modify listener
> attached (this fires when text is modified in field). e.g.
>
> sumInsuredText = new Text(this, SWT.BORDER);
> sumInsuredText.setLayoutData(gridData3);
> sumInsuredText.addModifyListener(new org.eclipse.swt.events.ModifyListener()
> {
>  public void modifyText(org.eclipse.swt.events.ModifyEvent e)
>  {
>   //.. do stuff ..
>   comp.refreshView();
>   //.. do other stuff ..
>  }
> });
>
> Unfortunately, refresh view updates the field too (it has to, as the purpose
> of the method is to update the contents in all the fields). This creates an
> infinite loop, as the initial modification triggers modifyText(), which
> called refreshView(), which triggers modifyText() etc.
>
> I need refreshView() to be called each time the field is updated - without
> causing an infinite loop. I'm not bothered whether this is on leaving the
> field (would probably prefer this actually) or whether it's when the text is
> changed.
>
> I guess this is a fairly common problem, and I wonder if anyone has any
> tried and tested solutions?

I would think that your best solution is to only trigger refreshView if
the old value differs from the new value.  I don't know about SWT, so
I'm not sure how you would implement this.

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Re: Field update loop pro "Daniel Pitts" <daniel.pitts@THRWHITE.remove-dii-this> - 2011-04-27 15:28 +0000

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