private void navigateTargets(@Nullable MouseEvent event, @NotNull List<? extends PsiElement> targets) {
    if (targets.isEmpty()) {
      if (myEmptyText != null) {
        if (event != null) {
          JComponent label = HintUtil.createErrorLabel(myEmptyText);
          label.setBorder(JBUI.Borders.empty(2, 7));
          JBPopupFactory.getInstance().createBalloonBuilder(label)
            .setFadeoutTime(3000)
            .setFillColor(HintUtil.getErrorColor())
            .createBalloon()
            .show(new RelativePoint(event), Balloon.Position.above);
        }
      }
    }
    else {
      navigateToItems(event);
    }
  }
private void navigateTargets(@Nullable MouseEvent event, @NotNull List<? extends PsiElement> targets)