Project Library UI - allow expanding libraries hierarchy even if there are no assets yet

src/bonsai/bonsai/bim/module/project/operator.py

@@ -237,7 +237,7 @@ class RefreshLibrary(bpy.types.Operator):
             elements.update(library_file.by_type(importable_type))
         rels = tool.Project.get_project_library_rels(library_file)
         elements = {e for e in elements if not tool.Project.is_element_assigned_to_project_library(e, rels)}
-        self.props.add_library_project_library("Unassigned", len(elements), 0)
+        self.props.add_library_project_library("Unassigned", len(elements), 0, False)
 
         ifc_project = library_file.by_type("IfcProject")[0]
         hierarchy = tool.Project.get_project_hierarchy(library_file)

src/bonsai/bonsai/bim/module/project/prop.py

@@ -180,6 +180,8 @@ class LibraryElement(PropertyGroup):
     element_type: EnumProperty(items=[(i, i, "") for i in get_args(LibraryElementType)], name="Element Type")
     # Asset group.
     asset_count: IntProperty(name="Asset Count")
+    # Asset library.
+    has_sublibraries: BoolProperty(name="Has Sublibraries", default=False)
     # Asset.
     ifc_definition_id: IntProperty(name="IFC Definition ID")
     is_declared: BoolProperty(name="Is Declared", default=False)
@@ -194,6 +196,7 @@ class LibraryElement(PropertyGroup):
         name: str
         element_type: LibraryElementType
         asset_count: int
+        has_sublibraries: bool
         ifc_definition_id: int
         is_declared: bool
         is_appended: bool
@@ -402,12 +405,15 @@ class BIMProjectProperties(PropertyGroup):
     def clipping_planes_objs(self) -> list[bpy.types.Object]:
         return list({cp.obj for cp in self.clipping_planes if cp.obj})
 
-    def add_library_project_library(self, name: str, asset_count: int, ifc_definition_id: int) -> LibraryElement:
+    def add_library_project_library(
+        self, name: str, asset_count: int, ifc_definition_id: int, has_sublibraries: bool
+    ) -> LibraryElement:
         new = self.library_elements.add()
         new["name"] = name
         new.asset_count = asset_count
         new.element_type = "LIBRARY"
         new.ifc_definition_id = ifc_definition_id
+        new.has_sublibraries = has_sublibraries
         return new
 
     def add_library_asset_class(self, name: str, asset_count: int) -> LibraryElement:

src/bonsai/bonsai/bim/module/project/ui.py

@@ -512,7 +512,7 @@ class BIM_UL_library(UIList):
     ):
         if item:
             row = layout.row(align=True)
-            if item.element_type != "ASSET" and item.asset_count > 0:
+            if item.element_type != "ASSET" and (item.asset_count > 0 or item.has_sublibraries):
                 op = row.operator("bim.change_library_element", text="", icon="DISCLOSURE_TRI_RIGHT", emboss=False)
                 op.element_name = item.name
                 op.breadcrumb_type = item.element_type

src/bonsai/bonsai/tool/project.py

@@ -377,7 +377,7 @@ class Project(bonsai.core.tool.Project):
                 sublibrary_elements = tool.Project.get_project_library_elements(sublibrary)
                 library_elements.update(sublibrary_elements)
             props.add_library_project_library(
-                project_library.Name or "Unnamed", len(library_elements), project_library.id()
+                project_library.Name or "Unnamed", len(library_elements), project_library.id(), bool(subhierarchy)
             )
 
     @classmethod