private void deleteKeys() {
TableItem containerItem = findContainerTableItem();
DeleteContainerDialog dialog = new DeleteContainerDialog(shell,
iconImage, questionImage, containerItem == null ? 0 : -1);
Boolean deleteSub = (Boolean) dialog.open();
if (deleteSub != null) {
TreeItem treeItem = null;
if (containerItem != null)
treeItem = getTreeItemByTableItem(containerItem)
.getParentItem();