From c23d4ff5b81d256a9edabcb5c7992f5eb47abdea Mon Sep 17 00:00:00 2001
From: Nick Randolph <nick@builttoroam.com>
Date: Tue, 21 Mar 2023 14:47:40 +1100
Subject: [PATCH] feat: Adjusting background brush for specified theme

(cherry picked from commit 5017a58b0fab47a7ab966de17dd15ae4a47514a3)
---
 .../.template.config/template.json            | 22 +++++++++++++++++++
 .../Presentation/MainPage.xaml                |  2 +-
 .../Presentation/SecondPage.xaml              |  2 +-
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/src/Uno.Extensions.Templates/content/unoapp-extensions/.template.config/template.json b/src/Uno.Extensions.Templates/content/unoapp-extensions/.template.config/template.json
index 8939de5466..6be7f55ef2 100644
--- a/src/Uno.Extensions.Templates/content/unoapp-extensions/.template.config/template.json
+++ b/src/Uno.Extensions.Templates/content/unoapp-extensions/.template.config/template.json
@@ -525,6 +525,28 @@
       "datatype": "bool",
       "value": "(appTheme == 'cupertino')"
     },
+    "themeBackgroundBrush":{
+      "type": "generated",
+      "generator": "switch",
+      "replaces": "$themeBackgroundBrush$",
+      "parameters": {
+        "evaluator": "C++",
+        "cases": [
+          {
+            "condition": "(appThemeEvaluator == 'material')",
+            "value": "BackgroundBrush"
+          },
+          {
+            "condition": "(appThemeEvaluator == 'fluent')",
+            "value": "ApplicationPageBackgroundThemeBrush"
+          },
+          {
+            "condition": "(appTheme == 'cupertino')",
+            "value": "CupertinoSystemBackgroundBrush"
+          }
+        ]
+      }
+    },
     "presetDependencyInjectionDefault": {
       "type": "generated",
       "generator": "switch",
diff --git a/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/MainPage.xaml b/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/MainPage.xaml
index 0a82594214..346e4ea76f 100644
--- a/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/MainPage.xaml
+++ b/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/MainPage.xaml
@@ -9,7 +9,7 @@
 	  xmlns:utu="using:Uno.Toolkit.UI"
 	  xmlns:not_skia="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 	  NavigationCacheMode="Required"
-	  Background="{ThemeResource BackgroundBrush}">
+	  Background="{ThemeResource $themeBackgroundBrush$}">
 
 	<Grid>
 		<Grid.RowDefinitions>
diff --git a/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/SecondPage.xaml b/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/SecondPage.xaml
index 0d8118ed9e..5466c95c8d 100644
--- a/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/SecondPage.xaml
+++ b/src/Uno.Extensions.Templates/content/unoapp-extensions/MyExtensionsApp.1/Presentation/SecondPage.xaml
@@ -6,7 +6,7 @@
 	  xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 	  xmlns:uen="using:Uno.Extensions.Navigation.UI"
 	  xmlns:utu="using:Uno.Toolkit.UI"
-	  Background="{ThemeResource BackgroundBrush}">
+	  Background="{ThemeResource $themeBackgroundBrush$}">
 
 	<Grid>
 		<utu:NavigationBar Content="Second Page">