Hi. I'm trying to create a multiple-targeting library for Xamarin(Android, IOS and UWP.) I examined project files of some multi-targeting xamarin libraries. (Such as Rg.Plugins.Popup, Xamarin.Essentials, MvvmCross) and edited the csproj file of my library(XamTemel.Ortak) like this.
<Project Sdk="MSBuild.Sdk.Extras/3.0.22">
<PropertyGroup>
<TargetFrameworks>netstandard2.0;Xamarin.iOS10;monoandroid10.0;</TargetFrameworks>
<TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);uap10.0.17763;</TargetFrameworks>
<DebugType>portable</DebugType>
<Configurations>Debug;Release</Configurations>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)'=='Debug' ">
<DebugSymbols>true</DebugSymbols>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)'=='Release' And '$(OS)' == 'Windows_NT' ">
<!-- sourcelink: Declare that the Repository URL can be published to NuSpec -->
<PublishRepositoryUrl>true</PublishRepositoryUrl>
<!-- sourcelink: Embed source files that are not tracked by the source control manager to the PDB -->
<EmbedUntrackedSources>true</EmbedUntrackedSources>
<!-- sourcelink: Include PDB in the built .nupkg -->
<AllowedOutputExtensionsInPackageBuildOutputFolder>$(AllowedOutputExtensionsInPackageBuildOutputFolder);.pdb</AllowedOutputExtensionsInPackageBuildOutputFolder>
</PropertyGroup>
<ItemGroup>
<Compile Remove="Platforms\**\*.cs" />
<None Include="Platforms\**\*.cs" />
</ItemGroup>
<ItemGroup Condition=" $(TargetFramework.StartsWith('monoandroid')) ">
<None Remove="Platforms\Android\**\*.cs" />
<None Remove="Platforms\Xamarin\**\*.cs" />
<Compile Include="Platforms\Android\**\*.cs" />
<Compile Include="Platforms\Xamarin\**\*.cs" />
<AndroidResource Include="Resources\**\*.xml" SubType="Designer" Generator="MSBuild:UpdateAndroidResources" />
<AndroidResource Include="Resources\**\*.json" Generator="MSBuild:UpdateAndroidResources" />
</ItemGroup>
<ItemGroup>
<PackageReference Include="ColorPicker.Xamarin.Forms" Version="1.3.4.11" />
</ItemGroup>
</Project>
As you can see I am going to put platform renderers in Platform/Android-IOS-UWP etc. Not this works fine on Android. But ColorPicker library gives me this error on UWP.

I don't understand why it cannot find ColorPicker. Version number seems okay. What am i doing wrong?
Here is the sample solution.
https://drive.google.com/file/d/1PnqFyzDmTBom6GH9YVdbyBvNwikitYlC/view?usp=sharing