WIP refactor context UI into its own module. Remove dependency to Blender properties. See #1222.

src/ifcblenderexport/blenderbim/bim/module/context/operator.py

@@ -0,0 +1,37 @@
+import bpy
+import blenderbim.bim.ifc
+import blenderbim.bim.module.context.add_context as add_context
+import blenderbim.bim.module.context.remove_context as remove_context
+from blenderbim.bim.module.context.data import Data
+
+class AddSubcontext(bpy.types.Operator):
+    bl_idname = "bim.add_subcontext"
+    bl_label = "Add Subcontext"
+
+    def execute(self, context):
+        self.file = blenderbim.bim.ifc.IfcStore.get_file()
+        usecase = add_context.Usecase(self.file, {
+            "context": bpy.context.scene.BIMProperties.available_contexts,
+            "subcontext": bpy.context.scene.BIMProperties.available_subcontexts,
+            "target_view": bpy.context.scene.BIMProperties.available_target_views,
+        })
+        result = usecase.execute()
+
+        Data.load()
+        return {"FINISHED"}
+
+
+class RemoveSubcontext(bpy.types.Operator):
+    bl_idname = "bim.remove_subcontext"
+    bl_label = "Remove Context"
+    ifc_definition_id: bpy.props.IntProperty()
+
+    def execute(self, context):
+        self.file = blenderbim.bim.ifc.IfcStore.get_file()
+        usecase = remove_context.Usecase(self.file, {
+            "context": self.file.by_id(self.ifc_definition_id)
+        })
+        usecase.execute()
+
+        Data.load()
+        return {"FINISHED"}