Prevent Tree Node from collapsing

[daddycocoaman]

I have a Tree that I would like to display items with arbitrary amounts of child items. However, some of the parent items are also options that can be selected to process Tree.NodeSelected events. When these nodes are clicked, the node will collapse or expand. However, I would like to not have these nodes collapsible.

I'm pretty sure I can handle this by subclassing Tree and overriding Tree._toggle_node() but would it be possible to make this a first-class feature similar to node.allow_expand?

Here is the code I'm currently using:

class NoncollapsibleTree(Tree):
    def _toggle_node(self, node: TreeNode) -> None:
        if not node.allow_expand:
            return

        if not node.is_expanded:
            node.expand()

[TomJGooding]

I think you can currently achieve this without overriding any methods by setting expand=True but allow_expand=False?

from textual.app import App, ComposeResult
from textual.widgets import Tree


class TreeApp(App):
    def compose(self) -> ComposeResult:
        tree = Tree("Root")
        tree.root.expand()

        node_one = tree.root.add("Node 1", expand=True, allow_expand=False)
        node_one.add_leaf("Node 1.1")
        node_one.add_leaf("Node 1.2")

        node_two = tree.root.add("Node 2", expand=True, allow_expand=False)
        node_two.add_leaf("Node 2.1")
        node_two.add_leaf("Node 2.2")

        yield tree


if __name__ == "__main__":
    app = TreeApp()
    app.run()

[daddycocoaman]

You know what, I dunno how I looked right at that function and didn't put that together. That works even better since it avoids unnecessary expand cursors. Thanks.