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New Developer
Posts: 30
Registered: ‎11-25-2009
My Device: Not Specified

Debugger message: FocusNullField

I believe I have a machine configuration problem, but can't seem to resolve it.


I have an app that was running fine using Eclipse 3.5.1 on machine A. After upgrading, the 4.6.0 simulator would hang. Various attempts to resolve this failed, so I moved the code over to machine B but used the BB JDE instead. Simulator worked fine. The JDE doesn't allow me to do some things like get code quality metrics, etc., so I copied the code back over to machine A in order to be able to do these things. Now the simulator hangs in both Galileo and in the BBJDE on machine A.


Here's the last debugger msg before the hang.


FocusHistory: Focus lost; App Phone; Component net.rim.device.api.ui.container.DialogFieldManager$FocusNullField


Any suggestions re: tracking down the source of the problem on machine A would be appreciated.

BlackBerry Development Advisor
Posts: 15,888
Registered: ‎07-09-2008
My Device: BlackBerry PRIV
My Carrier: Bell

Re: Debugger message: FocusNullField

Try running the clean.bat file located in the simulator directory (JDE) or using the Project -> BlackBerry -> Clean Simulator menu option in Eclipse.  This resets the simulator back to its default state.


When it hangs, do you see a UI in the simulator or a plain white screen?  If it is a plain white screen try turning the graphics acceleration options down.  To do so click on the View menu in the simulator and choose Graphics Acceleration.  Change to a lower value until you see a non white screen.

Mark Sohm
BlackBerry Development Advisor

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New Developer
Posts: 30
Registered: ‎11-25-2009
My Device: Not Specified

Re: Debugger message: FocusNullField

Thanks, Mark


I had tried clean.bat to no avail. I will try again this week and let you know.