展开包含所选项目的TreeView(父)节点 [英] expand TreeView (parent)nodes which contains selected item

问题描述

我有一个存在于User对象之外的TreeView. TreeView代表用户的层次结构:

I have a TreeView existing out of User objects. The TreeView represents the hierarchy of the Users:

• Master1
  • Super1
  • 超级2
    • User1
    • User2
    • Master1
      • Super1
      • Super2
        • User1
        • User2
        • User3

        初始化TreeView时，每个TreeItem都会折叠.但是，可能是在加载FXML时，从另一个FXML文件传递了TreeItem对象.例如:User3已通过:

        Every TreeItem is Collapsed when the TreeView is initialized. However, it can be that when the FXML is loaded, a TreeItem object is passed through from another FXML file. Eg: User3 has been passed through:

        selectedUserTreeItem = (TreeItem<User>) currentNavigation.getPassthroughObject(); //this is the User3 TreeItem
        

        我尝试使用递归函数来扩展selecterUserTreeItem

        I try to use a recursive function to expand all the parent nodes from the selecterUserTreeItem

        if (selectedUserTreeItem != null) {
            expandTreeView(selectedUserTreeItem);
        }
        
        tvUsers.setRoot(rootItem);
        

        这是我到目前为止所拥有的:

        This is what I have so far:

        private void expandTreeView(TreeItem<User> selectedItem) {        
            if (selectedItem != null) {
                System.out.println(selectedItem);
                if (selectedItem.isLeaf() == false) {
                    selectedItem.setExpanded(true);
                }
                TreeItem<User> parent = selectedItem.getParent();
                expandTreeView(parent);
            } else {
                System.out.println("null");
            }
        }
        

        我认为它必须做一些事情，即该函数是一个void函数，它应该返回一个我猜想的TreeItem对象，但是由于某种原因，我没有成功完成它.

        I think it has to do something with the fact that the function is a void function and it should be returning a TreeItem object I suppose but for some reason I don't succeed in doing it.

        有人能指出我正确的方向吗?

        Could someone point me in the right direction?

        推荐答案

        好吧，我注意到在您的expandTreeView()方法中，您将节点展开，然后递归到前一个节点以对其进行展开.在我自己的代码中，我从根扩展到了叶，所以让我们尝试一下:

        Ok, I notice that in your expandTreeView() method you expand the node and then you recurse to the previous node to expand that. In my own code I expanded from the root to the leaf, so lets try that:

        private void expandTreeView( TreeItem<User> selectedItem ) 
        {
            if ( selectedItem != null ) 
            {
                expandTreeView( selectedItem.getParent() );
        
                if ( ! selectedItem.isLeaf() ) 
                {
                    selectedItem.setExpanded( true );
                }
            }
        }
        

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