title: Problems occurred when invoking code from plug-in: "org.eclipse.jface"
body: <p>I'm new to all this and am following the HelloWorld tutorial. I got it run programmatically but when I try to do it using XML I get the message above in the log file when I try to run it. Basically every time I attempt to add a character to the strings.xml file in the res/layout directory I get an error window with the java.lang.NullPointerException. I can just click ok and continue editing the XML but when I view the error log I get the dump below and I can't figure out what to do. Have I not installed the plugin correctly. I installed 2.2</p>
  
  <pre><code>java.lang.NullPointerException
   at org.eclipse.wst.xml.core.internal.document.ElementImpl.getDefaultValue(ElementImpl.java:259)
   at org.eclipse.wst.xml.core.internal.document.ElementImpl.getAttributeNS(ElementImpl.java:329)
   at com.android.ide.eclipse.adt.internal.editors.uimodel.UiElementNode.getShortDescription(Unknown Source)
   at com.android.ide.eclipse.adt.internal.editors.ui.tree.UiModelTreeLabelProvider.getText(Unknown Source)
   at org.eclipse.jface.viewers.WrappedViewerLabelProvider.getText(WrappedViewerLabelProvider.java:108)
   at org.eclipse.jface.viewers.WrappedViewerLabelProvider.update(WrappedViewerLabelProvider.java:164)
   at org.eclipse.jface.viewers.ViewerColumn.refresh(ViewerColumn.java:152)
   at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:934)
   at org.eclipse.jface.viewers.AbstractTreeViewer$UpdateItemSafeRunnable.run(AbstractTreeViewer.java:102)
   at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
   at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
   at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
   at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:1014)
   at org.eclipse.jface.viewers.StructuredViewer$UpdateItemSafeRunnable.run(StructuredViewer.java:481)
   at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
   at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49)
   at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
   at org.eclipse.jface.viewers.StructuredViewer.updateItem(StructuredViewer.java:2141)
   at org.eclipse.jface.viewers.AbstractTreeViewer.updateChildren(AbstractTreeViewer.java:2689)
   at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefreshStruct(AbstractTreeViewer.java:1867)
   at org.eclipse.jface.viewers.TreeViewer.internalRefreshStruct(TreeViewer.java:721)
   at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh(AbstractTreeViewer.java:1842)
   at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh(AbstractTreeViewer.java:1799)
   at org.eclipse.jface.viewers.AbstractTreeViewer.internalRefresh(AbstractTreeViewer.java:1785)
   at org.eclipse.jface.viewers.StructuredViewer$7.run(StructuredViewer.java:1487)
   at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1422)
   at org.eclipse.jface.viewers.TreeViewer.preservingSelection(TreeViewer.java:403)
   at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1383)
   at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:1485)
   at org.eclipse.jface.viewers.ColumnViewer.refresh(ColumnViewer.java:537)
   at org.eclipse.jface.viewers.StructuredViewer.refresh(StructuredViewer.java:1444)
   at com.android.ide.eclipse.adt.internal.editors.ui.tree.UiTreeBlock$2.uiElementNodeUpdated(Unknown Source)
   at com.android.ide.eclipse.adt.internal.editors.uimodel.UiElementNode.invokeUiUpdateListeners(Unknown Source)
   at com.android.ide.eclipse.adt.internal.editors.uimodel.UiElementNode.loadFromXmlNode(Unknown Source)
   at com.android.ide.eclipse.adt.internal.editors.resources.ResourcesEditor.xmlModelChanged(Unknown Source)
   at com.android.ide.eclipse.adt.internal.editors.AndroidEditor$XmlModelStateListener.modelChanged(Unknown Source)
   at org.eclipse.wst.sse.core.internal.model.AbstractStructuredModel.fireModelChanged(AbstractStructuredModel.java:553)
   at org.eclipse.wst.sse.core.internal.model.AbstractStructuredModel.internalModelChanged(AbstractStructuredModel.java:887)
   at org.eclipse.wst.sse.core.internal.model.AbstractStructuredModel.changedModel(AbstractStructuredModel.java:382)
   at org.eclipse.wst.xml.core.internal.document.DOMModelImpl.changedModel(DOMModelImpl.java:167)
   at org.eclipse.wst.sse.core.internal.model.AbstractStructuredModel$DocumentToModelNotifier.regionChanged(AbstractStructuredModel.java:164)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument._fireEvent(BasicStructuredDocument.java:542)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument.fireStructuredDocumentEvent(BasicStructuredDocument.java:1181)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument.internalReplaceText(BasicStructuredDocument.java:1964)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument.replaceText(BasicStructuredDocument.java:2419)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument.replaceText(BasicStructuredDocument.java:2404)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument.access$2(JobSafeStructuredDocument.java:1)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument$3.run(JobSafeStructuredDocument.java:141)
   at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
   at org.eclipse.wst.sse.ui.EditorExecutionContext.execute(EditorExecutionContext.java:149)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument.replaceText(JobSafeStructuredDocument.java:144)
   at org.eclipse.wst.sse.core.internal.text.BasicStructuredDocument.replace(BasicStructuredDocument.java:2364)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument.access$0(JobSafeStructuredDocument.java:1)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument$1.run(JobSafeStructuredDocument.java:103)
   at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
   at org.eclipse.wst.sse.ui.EditorExecutionContext.execute(EditorExecutionContext.java:149)
   at org.eclipse.wst.sse.core.internal.text.JobSafeStructuredDocument.replace(JobSafeStructuredDocument.java:106)
   at org.eclipse.jface.text.projection.ProjectionTextStore.replace(ProjectionTextStore.java:111)
   at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1184)
   at org.eclipse.jface.text.AbstractDocument.replace(AbstractDocument.java:1210)
   at org.eclipse.jface.text.projection.ProjectionDocument.replace(ProjectionDocument.java:629)
   at org.eclipse.jface.text.DefaultDocumentAdapter.replaceTextRange(DefaultDocumentAdapter.java:248)
   at org.eclipse.swt.custom.StyledText.modifyContent(StyledText.java:7168)
   at org.eclipse.swt.custom.StyledText.sendKeyEvent(StyledText.java:7975)
   at org.eclipse.swt.custom.StyledText.doBackspace(StyledText.java:2267)
   at org.eclipse.swt.custom.StyledText.invokeAction(StyledText.java:6976)
   at org.eclipse.swt.custom.StyledText.handleKey(StyledText.java:5932)
   at org.eclipse.swt.custom.StyledText.handleKeyDown(StyledText.java:5958)
   at org.eclipse.swt.custom.StyledText$7.handleEvent(StyledText.java:5652)
   at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
   at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
   at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1077)
   at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1062)
   at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1103)
   at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1099)
   at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1508)
   at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:4268)
   at org.eclipse.swt.widgets.Canvas.WM_CHAR(Canvas.java:345)
   at org.eclipse.swt.widgets.Control.windowProc(Control.java:4160)
   at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:341)
   at org.eclipse.swt.widgets.Display.windowProc(Display.java:4873)
   at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
   at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:2459)
   at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3655)
   at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2629)
   at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2593)
   at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2427)
   at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:670)
   at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
   at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:663)
   at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
   at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:115)
   at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
   at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
   at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
   at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:369)
   at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  </code></pre>