Keyboard not working on front panel

Question

There must be something strange going on here, because this seems like a pretty weird problem.
I have several numeric controls on my front panel and an event loop inside a while loop on the diagram. My numeric controls are located inside the while loop, but outside the event loop.
When I start my VI, I lose the ability to change any numeric control values with my keyboard. I can't backspace, type numbers, delete, nothing. Even when I stop the VI, I still can't change any numbers with my keyboard. If bring the block diagram to the front, then bring the front panel back to the front, I can type in the boxes again.
I have an IE ActiveX control on my front panel as well... could it be stealing keyboard focus?

Answer 1

I'm not the only one with this problem then.  I just found this thread after spending several days tearing my hair out.  The keyboard focus is not switching from the embedded ActiveX control to the VI when the user clicks on the VI panel itself.
I've attached a simple VI that illustrates the problem.  In my case I'm using the Adobe (Acrobat) Reader ActiveX control.  Clearly the problem is at the LabVIEW end, as we're all using different ActiveX controls.  Adobe Reader is required to run this VI.  I'm using Adobe Reader 8.1.0 and LabVIEW 8.20.
The VI saves a small PDF file in your temp directory, then gets the Adobe Viewer to display it.  The PDF file is deleted on exit.
To illustrate the problem, try this:
Click on the PDF document then press F1.  The Adobe help is displayed.  Correct behaviour.
Click on the VI panel outside of the Adobe control then press F1.  The VI's help dialog is displayed.  Correct behaviour.
Click within the Find box at the top of the PDF document and type some numbers in.  Works correctly.
Now click within the numeric control at the bottom left of the VI and try to type some numbers in.  The numbers appear in the Adobe control.  Not correct behaviour.
I've found that if I press F1 after clicking on the VI or operate the boolean control with the mouse then the focus does correctly switch back to the VI.  I can then type numbers into the control following this.  However, after I've clicked anywhere on the ActiveX control I can click as much as I like on the VI panel or the numeric control and the focus will not switch to the VI's numeric control.
I believe that the fault is that the keyboard focus does not leave the ActiveX control until a LabVIEW boolean control is operated.  This means my application doesn't work properly.
I will submit a fault report for this, but any clever workaround would be very much appreciated.  I'm going to have a play with some of the events, e.g. mouse over the numeric and see if I can come up with anything.  I will report back if I get anywhere.
Message Edited by Sean on 08-07-2007 11:27 AM
Message Edited by Sean on 08-07-2007 11:29 AM
Attachments:
PDFView.vi ‏42 KB
PDFView.jpg ‏32 KB