the error message print on JFram on Net beans

[Tarfa man]

Hello there,


I face problem when design the user interface the error message is print on gui (JFrame)
like this




What is the problem ?
really this problem is affect on my work .

I download a new version of Net beans but same problem is still found.


the error message

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at javax.swing.AbstractButton.isSelected(AbstractButton.java:308)
    at javax.swing.ButtonGroup.add(ButtonGroup.java:76)
    at lightofproject.gui.DiagnoseSystemV_1.initComponents(DiagnoseSystemV_1.java:109)
    at lightofproject.gui.DiagnoseSystemV_1.<init>(DiagnoseSystemV_1.java:31)
    at lightofproject.gui.DiagnoseSystemV_1$2.run(DiagnoseSystemV_1.java:695)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

please ,the case is very critical on my work.

[Michael Dunn]

> the error message...

> What is the problem ? 

the problem is clearly stated on the first
line of the error message

[Tarfa man]

Michael Dunn wrote:> the error message...

> What is the problem ? 

the problem is clearly stated on the first
line of the error message

How I can solve it?

[Darryl Burke]

The solution is in the second sentence on the first line of the error message.

[Tarfa man]

the code is work now ..
after remove this line

noQ3_1.setModel(null);

but is still the error is print on JFrame , I can't deal with components ,,
please help me..

this is the second time of re-write my code ,

My OS is Win 7 and NB 7.1.2

[Michael Dunn]

> How I can solve it? 

read the error message
go where it points you
fix what it tells you