Merge pull request #2900 from leeagustin/allow-strings-in-layout-list

Allow strings in layout list

CHANGELOG.md

@@ -13,6 +13,7 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 - [#2898](https://github.com/plotly/dash/pull/2898) Fix error thrown when using non-existent components in callback running keyword. Fixes [#2897](https://github.com/plotly/dash/issues/2897).
 - [#2892](https://github.com/plotly/dash/pull/2860) Fix ensures dcc.Dropdown menu maxHeight option works with Datatable. Fixes [#2529](https://github.com/plotly/dash/issues/2529) [#2225](https://github.com/plotly/dash/issues/2225)
 - [#2896](https://github.com/plotly/dash/pull/2896) The tabIndex parameter of Div can accept number or string type. Fixes [#2891](https://github.com/plotly/dash/issues/2891)
+- [#2900](https://github.com/plotly/dash/pull/2900) Allow strings in layout list. Fixes [#2890](https://github.com/plotly/dash/issues/2890)
 - [#2908](https://github.com/plotly/dash/pull/2908) Fix when environment variables are ignored by Dash.run() at runtime. Fixes [#2902](https://github.com/plotly/dash/issues/2902)
 
 ## [2.17.1] - 2024-06-12

dash/_validate.py

@@ -439,11 +439,13 @@ def _validate_id(comp):
 
     if isinstance(layout_value, (list, tuple)):
         for component in layout_value:
+            if isinstance(component, (str,)):
+                continue
             if isinstance(component, (Component,)):
                 _validate(component)
             else:
                 raise exceptions.NoLayoutException(
-                    "List of components as layout must be a list of components only."
+                    "Only strings and components are allowed in a list layout."
                 )
     else:
         _validate(layout_value)

tests/integration/test_integration.py

@@ -433,6 +433,8 @@ def test_inin028_layout_as_list(dash_duo):
     app = Dash()
 
     app.layout = [
+        "string1",
+        "string2",
         html.Div("one", id="one"),
         html.Div("two", id="two"),
         html.Button("direct", id="direct"),
@@ -458,6 +460,9 @@ def on_nested_click(n_clicks):
 
     dash_duo.start_server(app)
 
+    dash_duo.wait_for_contains_text("#react-entry-point", "string1")
+    dash_duo.wait_for_contains_text("#react-entry-point", "string2")
+
     dash_duo.wait_for_text_to_equal("#one", "one")
     dash_duo.wait_for_text_to_equal("#two", "two")