Composite editorComposite = createComposite(topControl);
editorComposite.setLayoutData(
gdFillDefaults().grab(true, false).create());
editorComposite.setLayout(GridLayoutFactory.swtDefaults().numColumns(2).margins(0, 0).create());
treeViewer = new TreeViewerExt(editorComposite, SWT.SINGLE | SWT.BORDER);
treeViewer.setContentProvider(new ElementContentProvider2());
treeViewer.setLabelProvider(new LabeledTreeElementLabelProvider());
treeViewer.getTree().setLayoutData(
gdFillDefaults().hint(pc.convertWidthInCharsToPixels(40), pc.convertHeightInCharsToPixels(10)).create());
treeViewer.addSelectionChangedListener(new ISelectionChangedListener() {