Automating macOS application icon creation

[aelij]

Using the net8.0-macos TFM creates a macOS app package for Avalonia. However in order to create an icon one has to manually create the images in multiple sizes and run a tool to create a .icns file. MAUI has a way to create an app icon from SVG, including all the necessary PNGs and .plist updates. I've managed to make both of them work together, so I thought you may want to publish this as a NuGet to assist others.

Caveat - is is a bit hacky.

1. Reference the Microsoft.Maui.Resizetizer package.
2. Set the package icon to an SVG file:

   <ItemGroup>
      <MauiIcon Include="../../docs/roslynpad.svg" />
   </ItemGroup>

3. Set a few properties - note the .appiconset path should match the SVG filename:

     <PropertyGroup>
       <_ResizetizerIsiOSApp>true</_ResizetizerIsiOSApp>
       <ResizetizerIncludeSelfProject>true</ResizetizerIncludeSelfProject>
       <OptimizePNGs>true</OptimizePNGs>
       <_XSAppIconAssets>Assets.xcassets/roslynpad.appiconset</_XSAppIconAssets>
     </PropertyGroup>

4. Add the following targets:

   <Target Name="Before_CoreCompileImageAssets" BeforeTargets="_CoreCompileImageAssets">
     <PropertyGroup>
       <Original_SdkPlatform>$(_SdkPlatform)</Original_SdkPlatform>
       <_SdkPlatform>MacCatalyst</_SdkPlatform>
       <Original_UIDeviceFamily>$(_UIDeviceFamily)</Original_UIDeviceFamily>
       <_UIDeviceFamily>IPad</_UIDeviceFamily>
       <Original_ComputedTargetFrameworkMoniker>$(_ComputedTargetFrameworkMoniker)</Original_ComputedTargetFrameworkMoniker>
       <_ComputedTargetFrameworkMoniker>$(_ComputedTargetFrameworkMoniker.Replace('=macos', '=maccatalyst'))</_ComputedTargetFrameworkMoniker>
     </PropertyGroup>
   </Target>
   <Target Name="After_CoreCompileImageAssets" AfterTargets="_CoreCompileImageAssets">
     <PropertyGroup>
       <_SdkPlatform>$(Original_SdkPlatform)</_SdkPlatform>
       <_UIDeviceFamily>$(Original_UIDeviceFamily)</_UIDeviceFamily>
       <_ComputedTargetFrameworkMoniker>$(Original_ComputedTargetFrameworkMoniker)</_ComputedTargetFrameworkMoniker>
     </PropertyGroup>
   </Target>

A similar solution might work for icon bundling in other platforms.

[nixtar]

I've tried to reproduce this in one of my projects but I can't see any evidence that resizetizer is doing anything at all.

Should I see something in the build output/logs?

Do you also need to set the info.plist for the icon or does MauiIcon handle this?

[aelij]

Are you using the net8.0-macos target framework?
See a working example here - https://github.com/roslynpad/roslynpad/blob/main/src/RoslynPad.Avalonia/RoslynPad.Avalonia.csproj

[nixtar]

Sorry for late reply. Yes using net8.0-macos and I copied it from you RoslynPad repo exactly..

I ended up just doing it the hard way and manually creating the AppIcon.appiconset and referencing it in the Info.plist.