refs.leaves.tree

Module nustd.ui.refs.leaves.tree.

TreeRef -- nested rows that fold, with select, open, rename and move.

The server owns the nodes, the browser owns the moment. The nodes are a flat list the server ships whole; which rows are open and which one is selected the browser keeps as you click, and the server can set either. Everything the user does arrives as one notify on the tree, its kind named in the payload's event field, and each on_* takes only its own kind:

class Files(nustd.ui.Page):
    tree = nustd.ui.TreeRef.slot(label="Files", editable=True, draggable=True)

nu.ReactForever(Files.tree.on_open(), lambda ev: open_file(ev["key"]))
nu.ReactForever(Files.tree.on_rename(), lambda ev: rename(ev["key"], ev["title"]))

The browser never changes the nodes itself. A rename or a move is a request: the server applies it to whatever the tree stands for and ships the nodes again with set. A request the server turns down leaves the tree as it was.

A node is {key, parent, label} plus, optionally, icon (a short string, eg an emoji) and badge (a short string after the label). parent is another node's key, or None / "" at the top. Siblings keep the order they arrive in.

TreeRef

Nested rows that fold. The server owns the nodes; the browser reports what you do.

TreeRef(address, parent_ref=None, owner_shape=None, props=None)

Path nustd.ui.TreeRef. Kind Ref, sort ref, cardinality scalar.

Methods

.set(nodes)

Replace every node. Open rows and the selection stay where they still apply.

Builds Nu.

Arguments

Undocumented: example.

.set_selected(key)

Select a row; "" selects none.

Builds Nu.

Arguments

Undocumented: example.

.set_expanded(keys)

Open exactly these rows.

Builds Nu.

Arguments

Undocumented: example.

.on_change()

Every event below, each naming itself in event.

Builds Changed.

Undocumented: example.

.on_select()

{event, key}: a click or Space on a row.

Builds Changed.

Undocumented: example.

.on_open()

{event, key}: Enter or a double click, the row's "do the thing".

Builds Changed.

Undocumented: example.

.on_toggle()

{event, key, open}: a row folded or unfolded.

Builds Changed.

Undocumented: example.

.on_rename()

{event, key, title}: an inline rename, trimmed and changed. Needs editable.

Builds Changed.

Undocumented: example.

.on_move()

{event, key, parent, index}: a drop. Needs draggable.

Builds Changed.

parent "" is the top level; index counts the parent's children without key.

Undocumented: example.

Inherited methods

From nustd.ui.core.base.Ref:

Undocumented: example.