add Placeholder example test and images

Author: OwenMcDonnell

sdk/python/examples/controls/placeholder/__init__.py

@@ -5,9 +5,13 @@ def main(page: ft.Page):
     page.add(
         ft.Placeholder(
             expand=True,
-            color=ft.Colors.random(),
+            color=ft.Colors.GREEN_ACCENT,
+            fallback_height=200,
+            fallback_width=300,
+            stroke_width=20,
         )
     )
 
 
-ft.run(main)
+if __name__ == "__main__":
+    ft.run(main)

sdk/python/examples/controls/placeholder/basic.py

@@ -1,10 +1,10 @@
 ---
 class_name: flet.Placeholder
 examples: ../../examples/controls/placeholder
-example_images: ../examples/controls/placeholder/media
+example_images: ../test-images/examples/core/golden/macos/placeholder
 ---
 
-{{ class_summary(class_name) }}
+{{ class_summary(class_name, example_images + "/image_for_docs.png", image_caption="Placeholder") }}
 
 ## Examples
 

sdk/python/packages/flet/docs/controls/placeholder.md

@@ -0,0 +1,37 @@
+import pytest
+
+import flet as ft
+import flet.testing as ftt
+
+from examples.controls.placeholder import basic
+
+
+# @pytest.mark.asyncio(loop_scope="function")
+# async def test_image_for_docs(flet_app_function: ftt.FletTestApp, request):
+#     flet_app_function.page.theme_mode = ft.ThemeMode.LIGHT
+#     await flet_app_function.assert_control_screenshot(
+#         request.node.name,
+#         ft.Placeholder(
+#             expand=True,
+#             color=ft.Colors.RED_500,
+#         ),
+#     )
+
+
+@pytest.mark.parametrize(
+    "flet_app_function",
+    [{"flet_app_main": basic.main}],
+    indirect=True,
+)
+@pytest.mark.asyncio(loop_scope="function")
+async def test_basic(flet_app_function: ftt.FletTestApp):
+    flet_app_function.page.enable_screenshots = True
+    flet_app_function.resize_page(200, 200)
+    flet_app_function.page.update()
+    await flet_app_function.tester.pump_and_settle()
+    flet_app_function.assert_screenshot(
+        "basic",
+        await flet_app_function.page.take_screenshot(
+            pixel_ratio=flet_app_function.screenshots_pixel_ratio
+        ),
+    )

sdk/python/packages/flet/integration_tests/examples/core/golden/macos/placeholder/basic.png

@@ -46,13 +46,13 @@ async def test_image_for_docs(flet_app_function: ftt.FletTestApp, request):
     indirect=True,
 )
 @pytest.mark.asyncio(loop_scope="function")
-async def test_determinate_and_indeterminate(flet_app_function: ftt.FletTestApp):
+async def test_basic(flet_app_function: ftt.FletTestApp):
     flet_app_function.page.theme_mode = ft.ThemeMode.LIGHT
     flet_app_function.page.enable_screenshots = True
     pb = await flet_app_function.tester.find_by_key("popup")
     await flet_app_function.tester.tap(pb)
     await flet_app_function.tester.pump_and_settle()
     flet_app_function.assert_screenshot(
-        "determinate_and_indeterminate",
+        "basic",
         await flet_app_function.page.take_screenshot(delay=ft.Duration(seconds=15)),
     )

sdk/python/packages/flet/integration_tests/examples/core/golden/macos/placeholder/image_for_docs.png

@@ -13,6 +13,14 @@
 class Placeholder(LayoutControl):
     """
     A placeholder box.
+
+    ```python
+    ft.Placeholder(
+        expand=True,
+        color=ft.Colors.RED_500,
+    )
+    ```
+
     """
 
     content: Optional[Control] = None