When opening GUI with GUIDE I get errors and a weird behavior

I made a GUI with GUIDE, all was working fine until today when I was going to do some changes to it, although working fine when run from m file the GUIDE editor gives errors and it's very hard to modify and add more components, even matlab interface gets corrupted somehow, here's the error:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
  at com.mathworks.toolbox.matlab.guide.palette.MObjectProxy.paintWithDefaultProxy(MObjectProxy.java:226)
  at com.mathworks.toolbox.matlab.guide.palette.MObjectProxy.paint(MObjectProxy.java:200)
  at com.mathworks.toolbox.matlab.guide.palette.LOControlWrapper.paint(LOControlWrapper.java:322)
  at com.mathworks.toolbox.matlab.guide.LayoutArea.paintControlList(LayoutArea.java:2038)
  at com.mathworks.toolbox.matlab.guide.LayoutArea.paint(LayoutArea.java:2072)
  at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source)
  at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
  at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
  at java.awt.Container.paint(Unknown Source)
  at com.mathworks.toolbox.matlab.guide.scroll.ScrollPanel$Scroller.paint(ScrollPanel.java:413)
  at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source)
  at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
  at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
  at java.awt.Container.paint(Unknown Source)
  at com.mathworks.toolbox.matlab.guide.scroll.ScrollPanel.paint(ScrollPanel.java:124)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at javax.swing.JLayeredPane.paint(Unknown Source)
  at javax.swing.JComponent.paintChildren(Unknown Source)
  at javax.swing.JComponent.paintToOffscreen(Unknown Source)
  at javax.swing.BufferStrategyPaintManager.paint(Unknown Source)
  at javax.swing.RepaintManager.paint(Unknown Source)
  at javax.swing.JComponent.paint(Unknown Source)
  at java.awt.GraphicsCallback$PaintCallback.run(Unknown Source)
  at sun.awt.SunGraphicsCallback.runOneComponent(Unknown Source)
  at sun.awt.SunGraphicsCallback.runComponents(Unknown Source)
  at java.awt.Container.paint(Unknown Source)
  at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
  at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
  at javax.swing.RepaintManager.seqPaintDirtyRegions(Unknown Source)
  at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(Unknown Source)
  at java.awt.event.InvocationEvent.dispatch(Unknown Source)
  at java.awt.EventQueue.dispatchEvent(Unknown Source)
  at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
  at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
  at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
  at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
  at java.awt.EventDispatchThread.run(Unknown Source)

Matlab 2008b 32 bits, Windows 7 64 bits

I searched for an answer but no luck with solutions, rebuilding the GUI would be one but it's not a simple GUI.

Answer 1

[Bobane]

Have experienced this in the past. Most of the time, it disappears when I restart Matlab. Not too sure what causes it though.

[Paulo Silva]

no luck after restarting matlab and OS :( although using guide for years this is the first time java screws things up :(

Answer 2

[Sean de Wolski]

I get the java errors all of the time when creating figures (usually with imshow) but they don't seem to hurt anything so I just clc them away!

(OSX R2009b 64bit)

[Paulo Silva]

Sean the problem is bad, after loading the fig file matlab starts acting weird, corrupted menus, gui objects hard to move or add, etc.

Java errors are new for me, have experienced many problems using GUIDE but this time I'm really angry with it, used GUIDE just because it makes it easy and fast to do something but now I'm screwed and might have to do all again, maybe it's a good thing for me to finally stop using the stupid GUIDE!

[Sean de Wolski]

Sorry to hear that, and good luck. I finally scrapped GUIDE recently too. I would recommend downloading Matt Fig's GUI tutorial package, it makes the transition really painless.