Implement Ctrl-Tab in properties to conveniently toggle between two tabs.

src/blenderbim/blenderbim/bim/__init__.py

@@ -93,6 +93,7 @@ classes = [
     operator.ConfigureVisibility,
     operator.OpenUpstream,
     operator.OpenUri,
+    operator.SwitchTab,
     operator.ReloadIfcFile,
     operator.RemoveIfcFile,
     operator.SelectDataDir,
@@ -146,7 +147,7 @@ classes = [
 for mod in modules.values():
     classes.extend(mod.classes)
 
-
+addon_keymaps = []
 icons = None
 
 
@@ -184,6 +185,12 @@ def register():
     for mod in modules.values():
         mod.register()
 
+    wm = bpy.context.window_manager
+    if wm.keyconfigs.addon:
+        km = wm.keyconfigs.addon.keymaps.new(name='Window', space_type='EMPTY')
+        kmi = km.keymap_items.new('bim.switch_tab', 'TAB', 'PRESS', ctrl=True)
+        addon_keymaps.append((km, kmi))
+
     global icons
 
     icons_dir = os.path.join(cwd, "data", "icons")
@@ -237,3 +244,10 @@ def unregister():
 
     for mod in reversed(list(modules.values())):
         mod.unregister()
+
+    wm = bpy.context.window_manager
+    kc = wm.keyconfigs.addon
+    if kc:
+        for km, kmi in addon_keymaps:
+            km.keymap_items.remove(kmi)
+    addon_keymaps.clear()

src/blenderbim/blenderbim/bim/module/project/__init__.py

@@ -79,6 +79,7 @@ def register():
 def unregister():
     bpy.types.TOPBAR_MT_file.remove(ui.file_menu)
     del bpy.types.Scene.BIMProjectProperties
+
     wm = bpy.context.window_manager
     kc = wm.keyconfigs.addon
     if kc:

src/blenderbim/blenderbim/bim/operator.py

@@ -40,6 +40,18 @@ from mathutils import Vector, Matrix, Euler
 from math import radians
 
 
+class SwitchTab(bpy.types.Operator):
+    bl_idname = "bim.switch_tab"
+    bl_label = "Switch Tab"
+    bl_options = {"REGISTER", "UNDO"}
+    bl_description = "Switches to the last used tab"
+
+    def execute(self, context):
+        aprops = context.screen.BIMAreaProperties[context.screen.areas[:].index(context.area)]
+        aprops.tab = aprops.alt_tab
+        return {"FINISHED"}
+
+
 class OpenUri(bpy.types.Operator):
     bl_idname = "bim.open_uri"
     bl_label = "Open URI"

src/blenderbim/blenderbim/bim/prop.py

@@ -53,6 +53,11 @@ cwd = os.path.dirname(os.path.realpath(__file__))
 materialpsetnames_enum = []
 
 
+def update_tab(self, context):
+    self.alt_tab = self.previous_tab
+    self.previous_tab = self.tab
+
+
 def update_preset(self, context):
     from blenderbim.bim.data.ui.presets import presets
 
@@ -352,7 +357,9 @@ def get_tab(self, context):
 
 
 class BIMAreaProperties(PropertyGroup):
-    tab: EnumProperty(default=0, items=get_tab, name="Tab")
+    tab: EnumProperty(default=0, items=get_tab, name="Tab", update=update_tab)
+    previous_tab: StringProperty(default="PROJECT", name="Previous Tab")
+    alt_tab: StringProperty(default="PROJECT", name="Alt Tab")
 
 
 class BIMProperties(PropertyGroup):

src/blenderbim/blenderbim/bim/ui.py

@@ -279,7 +279,9 @@ class BIM_PT_root(Panel):
 
     def draw(self, context):
         aprops = context.screen.BIMAreaProperties[context.screen.areas[:].index(context.area)]
-        self.layout.prop(aprops, "tab", text="")
+        row = self.layout.row(align=True)
+        row.prop(aprops, "tab", text="")
+        row.operator("bim.switch_tab", text="", icon="UV_SYNC_SELECT")
 
 
 class BIM_PT_project_info(Panel):