Add targets file for WindowsXamlHost nugets to automaticly reference the Windows references

[nmetulev]

I'm submitting a...

• Feature request (UserVoice request: )

Current behavior

When developers use the WindowsXamlHost nuget packages they need to add all the references manually to use Windows UWP APIs: https://docs.microsoft.com/en-us/windows/uwp/porting/desktop-to-uwp-enhance#first-set-up-your-project

Expected behavior

The nuget packages should add those references automatically via a targets file

Environment

Nuget Package(s): 
Microsoft.Toolkit.Forms.UI.XamlHost
Microsoft.Toolkit.Wpf.UI.XamlHost

Package Version(s): 

Windows 10 Build Number:
- [ ] Fall Creators Update (16299)
- [ ] April 2018 Update (17134)
- [x] October 2018 Update (17763)
- [ ] Insider Build (build number: )

App min and target version:
- [ ] Fall Creators Update (16299)
- [ ] April 2018 Update (17134)
- [x] October 2018 Update (17763)
- [ ] Insider Build (xxxxx)

Device form factor:
- [x] Desktop
- [ ] Mobile
- [ ] Xbox
- [ ] Surface Hub
- [ ] IoT

Visual Studio 
- [x] 2017 (version: )
- [ ] 2017 Preview (version: )

[dotMorten]

I also thing this targets file should be able to find project references and copy its contentfiles, instead of the manual file copying

[rido-min]

The instructions you linked are being reviewed as we speak. The POR is to produce a NuGet package that will include the required Windows.winmd and the required System.Runtime assemblies.

[nmetulev]

That's great news @rido-min. Do you have a timeline for this nuget?

[rido-min]

The NuGet package will be owned by the Windows SDK team, they are targeting 19H1 timeframe, but we expect to have preview versions sooner. Do you need versions for previous SDKs as well?

/cc: @AdamBraden @marb2000 @loarabia

[nmetulev]

Current packages have a min version of rs5. Since XAML Islands is still in preview, I'd imagine there will be breaking changes in 19H1, makes sense to snap to that as soon as you have a preview.

[liquidboy]

so tried pulling this repo and building/running the tests. Encountered the missing windows references. I know the team is looking to make this more workflow friendly .

https://twitter.com/josefajardo/status/1088943046589218816

I manually added references to the relevant winmd's ..

And just to point out, my windows sdk is stored in drive "E:\Windows Kits" not the default "C:\Program Files (x86)\Windows Kits"