When deleting a source from a group in the card panel, using the Delete key, the source is properly removed. However if you press Delete a second time without interacting with any other UI elements, it attempts to delete again, but no group is present:
NPE On Repeated Delete of Source from Group
```java
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222)
at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179)
at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149)
at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47)
at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668)
at javax.swing.JComponent.processKeyBinding(JComponent.java:2882)
at javax.swing.JComponent.processKeyBindings(JComponent.java:2929)
at javax.swing.JComponent.processKeyEvent(JComponent.java:2845)
at java.awt.Component.processEvent(Component.java:6316)
at java.awt.Container.processEvent(Container.java:2239)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800)
at java.awt.Component.dispatchEventImpl(Component.java:4760)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Window.dispatchEventImpl(Window.java:2746)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
at java.awt.EventQueue$4.run(EventQueue.java:733)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222)
at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179)
at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149)
at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47)
at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668)
at javax.swing.JComponent.processKeyBinding(JComponent.java:2882)
at javax.swing.JComponent.processKeyBindings(JComponent.java:2929)
at javax.swing.JComponent.processKeyEvent(JComponent.java:2845)
at java.awt.Component.processEvent(Component.java:6316)
at java.awt.Container.processEvent(Container.java:2239)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800)
at java.awt.Component.dispatchEventImpl(Component.java:4760)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Window.dispatchEventImpl(Window.java:2746)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
at java.awt.EventQueue$4.run(EventQueue.java:733)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222)
at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179)
at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149)
at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47)
at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668)
at javax.swing.JComponent.processKeyBinding(JComponent.java:2882)
at javax.swing.JComponent.processKeyBindings(JComponent.java:2929)
at javax.
swing.JComponent.processKeyEvent(JComponent.java:2845)
at java.awt.Component.processEvent(Component.java:6316)
at java.awt.Container.processEvent(Container.java:2239)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
at java.awt.D
efaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800)
at java.awt.Component.dispatchEventImpl(Component.java:4760)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Window.dispatchEventImpl(Window.java:2746)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
at java.awt.EventQueue$4.run(EventQueue.java:733)
at java.a
wt.EventQueue$4.run(EventQueue.java:731)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222)
at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179)
at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149)
at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47)
at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668)
at javax.swing.JComponent.processKeyBinding(JComponent.java:2882)
at javax.swing.JComponent.processKeyBindings(JComponent.java:2929)
at javax.swing.JComponent.processKeyEvent(JComponent.java:2845)
at java.awt.Component.processEvent(Component.java:6316)
at java.awt.Container.processEvent(Container.java:2239)
at java.awt.Component.dispatchEventImpl(Component.java:4889)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835)
at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103)
at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974)
at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800)
at java.awt.Component.dispatchEventImpl(Component.java:4760)
at java.awt.Container.dispatchEventImpl(Container.java:2297)
at java.awt.Window.dispatchEventImpl(Window.java:2746)
at java.awt.Component.dispatchEvent(Component.java:4711)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
at java.awt.EventQueue$4.run(EventQueue.java:733)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
```
When deleting a source from a group in the card panel, using the
Delete
key, the source is properly removed. However if you pressDelete
a second time without interacting with any other UI elements, it attempts to delete again, but no group is present:NPE On Repeated Delete of Source from Group
```java Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222) at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179) at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149) at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47) at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668) at javax.swing.JComponent.processKeyBinding(JComponent.java:2882) at javax.swing.JComponent.processKeyBindings(JComponent.java:2929) at javax.swing.JComponent.processKeyEvent(JComponent.java:2845) at java.awt.Component.processEvent(Component.java:6316) at java.awt.Container.processEvent(Container.java:2239) at java.awt.Component.dispatchEventImpl(Component.java:4889) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954) at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835) at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103) at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974) at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800) at java.awt.Component.dispatchEventImpl(Component.java:4760) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Window.dispatchEventImpl(Window.java:2746) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84) at java.awt.EventQueue$4.run(EventQueue.java:733) at java.awt.EventQueue$4.run(EventQueue.java:731) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.awt.EventQueue.dispatchEvent(EventQueue.java:730) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222) at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179) at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149) at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47) at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668) at javax.swing.JComponent.processKeyBinding(JComponent.java:2882) at javax.swing.JComponent.processKeyBindings(JComponent.java:2929) at javax.swing.JComponent.processKeyEvent(JComponent.java:2845) at java.awt.Component.processEvent(Component.java:6316) at java.awt.Container.processEvent(Container.java:2239) at java.awt.Component.dispatchEventImpl(Component.java:4889) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954) at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835) at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103) at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974) at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800) at java.awt.Component.dispatchEventImpl(Component.java:4760) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Window.dispatchEventImpl(Window.java:2746) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84) at java.awt.EventQueue$4.run(EventQueue.java:733) at java.awt.EventQueue$4.run(EventQueue.java:731) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.awt.EventQueue.dispatchEvent(EventQueue.java:730) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222) at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179) at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149) at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47) at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668) at javax.swing.JComponent.processKeyBinding(JComponent.java:2882) at javax.swing.JComponent.processKeyBindings(JComponent.java:2929) at javax. swing.JComponent.processKeyEvent(JComponent.java:2845) at java.awt.Component.processEvent(Component.java:6316) at java.awt.Container.processEvent(Container.java:2239) at java.awt.Component.dispatchEventImpl(Component.java:4889) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954) at java.awt.D efaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835) at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103) at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974) at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800) at java.awt.Component.dispatchEventImpl(Component.java:4760) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Window.dispatchEventImpl(Window.java:2746) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84) at java.awt.EventQueue$4.run(EventQueue.java:733) at java.a wt.EventQueue$4.run(EventQueue.java:731) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.awt.EventQueue.dispatchEvent(EventQueue.java:730) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at bdv.ui.sourcegrouptree.SourceGroupTree.getSelectedSourcesInGroups(SourceGroupTree.java:222) at bdv.ui.sourcegrouptree.SourceGroupTree.removeSelected(SourceGroupTree.java:179) at bdv.ui.sourcegrouptree.SourceGroupTree.lambda$installActions$4(SourceGroupTree.java:149) at org.scijava.ui.behaviour.util.RunnableAction.actionPerformed(RunnableAction.java:47) at javax.swing.SwingUtilities.notifyAction(SwingUtilities.java:1668) at javax.swing.JComponent.processKeyBinding(JComponent.java:2882) at javax.swing.JComponent.processKeyBindings(JComponent.java:2929) at javax.swing.JComponent.processKeyEvent(JComponent.java:2845) at java.awt.Component.processEvent(Component.java:6316) at java.awt.Container.processEvent(Container.java:2239) at java.awt.Component.dispatchEventImpl(Component.java:4889) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954) at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835) at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103) at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974) at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800) at java.awt.Component.dispatchEventImpl(Component.java:4760) at java.awt.Container.dispatchEventImpl(Container.java:2297) at java.awt.Window.dispatchEventImpl(Window.java:2746) at java.awt.Component.dispatchEvent(Component.java:4711) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84) at java.awt.EventQueue$4.run(EventQueue.java:733) at java.awt.EventQueue$4.run(EventQueue.java:731) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74) at java.awt.EventQueue.dispatchEvent(EventQueue.java:730) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) ```