void (TreeSelectionEvent e) { SwingUtilities.invokeLater(() -> { final Set<PsiFile> searchIn = getSelectedScope(myLeftTree); final Set<PsiFile> searchFor = getSelectedScope(myRightTree); if (searchIn.isEmpty() || searchFor.isEmpty()) { myUsagesPanel.setToInitialPosition(); processDependencies(searchIn, searchFor, path -> { searchFor.add(path.get(1)); return true; }); } else { myUsagesPanel.findUsages(searchIn, searchFor); } }); }