From da4dc26bad30e6e04bec66c6669196f1b53aecea Mon Sep 17 00:00:00 2001
From: ahall <ahall@cloudflare.com>
Date: Fri, 10 Jul 2026 19:25:47 +0100
Subject: [PATCH] fix: enable compiled Source binding to resolve XamlC XC0025
 in TodoApp.MAUI

MainPage.xaml's Entry.ReturnCommandParameter binds via an explicit
Source={x:Reference addItemEntry}, which XamlC does not compile by
default, producing a build warning (XC0025) and falling back to
slower reflection-based binding.

Enable MauiEnableXamlCBindingWithSourceCompilation project-wide and
annotate the binding with x:DataType=Entry so XamlC can compile it.
This is the only Source-based binding in the project, so no other
bindings are affected.

Fixes #517
---
 samples/todoapp/TodoApp.MAUI/MainPage.xaml       |  2 +-
 samples/todoapp/TodoApp.MAUI/TodoApp.MAUI.csproj | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/samples/todoapp/TodoApp.MAUI/MainPage.xaml b/samples/todoapp/TodoApp.MAUI/MainPage.xaml
index 0a804732..b06b9c36 100644
--- a/samples/todoapp/TodoApp.MAUI/MainPage.xaml
+++ b/samples/todoapp/TodoApp.MAUI/MainPage.xaml
@@ -55,7 +55,7 @@
                         Completed="OnAddItemEntryCompleted"
                         Placeholder="Enter Todo Item Text"
                         ReturnCommand="{Binding AddItemCommand}"
-                        ReturnCommandParameter="{Binding Text, Source={x:Reference addItemEntry}}"
+                        ReturnCommandParameter="{Binding Text, Source={x:Reference addItemEntry}, x:DataType=Entry}"
                         Style="{StaticResource addItemEntry}" />
                 </Grid>
             </Border>
diff --git a/samples/todoapp/TodoApp.MAUI/TodoApp.MAUI.csproj b/samples/todoapp/TodoApp.MAUI/TodoApp.MAUI.csproj
index df0379ee..c87993ae 100644
--- a/samples/todoapp/TodoApp.MAUI/TodoApp.MAUI.csproj
+++ b/samples/todoapp/TodoApp.MAUI/TodoApp.MAUI.csproj
@@ -43,6 +43,18 @@
       See https://github.com/CommunityToolkit/Datasync/issues/521.
     -->
     <SuppressTrimAnalysisWarnings Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'ios'">true</SuppressTrimAnalysisWarnings>
+
+    <!--
+      MainPage.xaml has one binding (Entry.ReturnCommandParameter) that sets an explicit
+      Source={x:Reference ...} instead of relying on the page's BindingContext. By default,
+      XamlC skips compiling any binding with an explicit Source, falling back to slower
+      reflection-based binding and emitting an XC0025 warning. Opting into this project-wide
+      flag lets XamlC compile that binding too, now that it's annotated with the correct
+      x:DataType for its Source (see MainPage.xaml). This project has no other Source-based
+      bindings, so there's no risk of newly-surfaced x:DataType mismatches elsewhere.
+      See https://github.com/CommunityToolkit/Datasync/issues/517.
+    -->
+    <MauiEnableXamlCBindingWithSourceCompilation>true</MauiEnableXamlCBindingWithSourceCompilation>
   </PropertyGroup>
 
   <ItemGroup>