Bug 64372 Projects showing up in Package Explorer twice [package explorer]
20040527-0800 When I load the platform-ui module and org.eclipse.tests from HEAD org.eclipse.tests is showing up twice in the PackageExplorer. This is not a a problem in the Resource Navigator. Open type only shows it once so it doesn't look like there are two instance in the workspace
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
private ProblemTreeViewer createViewer(Composite composite) {
		return  new PackageExplorerProblemTreeViewer(composite, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL);
	}
	/**
	 * Answers whether this part shows the packages flat or hierarchical.
	 * 
	 * @since 2.1
	 */
	boolean isFlatLayout() {
		return fIsCurrentLayoutFlat;
	}
	
	private void setProviders() {
		
		fContentProvider= createContentProvider();
		fContentProvider.setIsFlatLayout(fIsCurrentLayoutFlat);
		fViewer.setContentProvider(fContentProvider);
	
		fLabelProvider= createLabelProvider();
		fLabelProvider.setIsFlatLayout(fIsCurrentLayoutFlat);
		fViewer.setLabelProvider(new DecoratingJavaLabelProvider(fLabelProvider, false));
		
	}
	
	void toggleLayout() {
		
		fIsCurrentLayoutFlat= !fIsCurrentLayoutFlat;
		saveLayoutState(null);
		
		fContentProvider.setIsFlatLayout(isFlatLayout());