ExpandCollapseDoubleClickListener.java 文件源码

@Override
public void doubleClick(DoubleClickEvent event) {
    final IStructuredSelection selection = (IStructuredSelection) event.getSelection();
    if (selection == null || selection.isEmpty())
        return;
    final Object sel = selection.getFirstElement();

    final ITreeContentProvider provider = (ITreeContentProvider) viewer.getContentProvider();

    if (!provider.hasChildren(sel))
        return;

    if (viewer.getExpandedState(sel))
        viewer.collapseToLevel(sel, AbstractTreeViewer.ALL_LEVELS);
    else
        viewer.expandToLevel(sel, 1);

}