Multi Target UWP to 1809 and 2004

[inforithmics]

Description of Change

Bugs Fixed

• [Bug] Popup on UWP throws an exception when accessed from the nightly nuget #889

Probably Fixes

• AvatarView doesn't displays image #1129

API Changes

Adds Target Windows 17763 / 1809
Keeps Target Windows 19031 / 2004

Behavioral Changes

works now again on Windows 17763 / 1809

PR Checklist

• Has tests (if omitted, state reason in description)
  Has already tests
• Has samples (if omitted, state reason in description)
  Has already samples
• Rebased on top of main at time of PR
• Changes adhere to coding standard

• Updated documentation

[inforithmics]

Don't merge yet, seems not to work with Windows 1809

[inforithmics]

I picked the wrong uap version number now it should really target 1809 and 2004

[inforithmics]

It works now
nuget package under

https://dev.azure.com/xamarin/public/_build/results?buildId=39464&view=artifacts&pathAsName=false&type=publishedArtifacts

[jfversluis]

OK, so. This fixes the mentioned issues as it will sort out the SDK that needs to be targeted and it will automatically pick up on the shadows not being there for the popups for instance?

And this closes #942 and #1238 ?

[inforithmics]

As I mentioned in.

#1238 (comment)

When you Target for Min Windows 1809 Then the Transparent Background won't work because of this.

#if UWP_18362
if (Element.Color == Color.Transparent)
     flyoutStyle.Setters.Add(new Windows.UI.Xaml.Setter(FlyoutPresenter.IsDefaultShadowEnabledProperty, false));
#endif

The 1809 Target won't Compile the Code and therefore it won't be executed which means no Transparent Background for the Popup.

But it would solve the UWP Targeting issues. and close #942 and #1238?

If the Transparent Background should work

#if UWP_18362
if (Element.Color == Color.Transparent)
     flyoutStyle.Setters.Add(new Windows.UI.Xaml.Setter(FlyoutPresenter.IsDefaultShadowEnabledProperty, false));
#else
// Fixing Transparent Background for 1809 ....
#endif

would be needed

[jfversluis]

Right, I noticed that compiler directive in there, yet it breaks right now for people targeting different versions if I understand correctly

[inforithmics]

That's why I did the pull request #942
Where it Targets the 1809 But makes the newer properties available. But they need to be guarded by Api Checks

[inforithmics]

Maybe Multi Targeting and deciding by case by case basis what to do is saver than having runtime crashes.

For example in the develop branch

https://github.com/xamarin/XamarinCommunityToolkit/blob/develop/src/CommunityToolkit/Xamarin.CommunityToolkit/Effects/Shadow/PlatformShadowEffect.uwp.cs

View.ActualSize is used which is not availble under 1809 with compilation for 1809 and 2004 this would immediatly be detected.

Here I mentioned a possible Fix for 1809 with transparent background, But I have to this it First in Release (Linking Mode if it still works).

#1238 (comment)

[inforithmics]

I tested the changes and it works for an UWP App in the Debug Mode. But if I Native Compile it (Release) Popup does not work. Although the original Popup doesn't work in Release Mode. I have to investigate further what the problem could be. Maybe the wrong Release compilation Settings.

[inforithmics]

A fun fact I discovered is that the Xamarin.CommunityToolkit Nuget Package and Xamarin.CommunityToolkit Project behave differently in Version Resolution Management.

1. Original Nuget Targets 19031 / 2004 does not work in UWP App Targeting Min Version of 1809. So a Project using the nuget package doesn't work.
2. Original Project Targets 9031 / 2004 works in UWP App Targeting Min Version of 1809. So the Test Project works because it references the Xamarin.CommunityToolkit Project File.

[inforithmics]

I removed the Release Compilation Crash Fixes from this Pull Request, because they are reviewed in this Pull Request.

#1303

[bijington]

@inforithmics thank you for keeping this PR up to date. To give a brief heads up we are currently unsure what the best course of action is in terms of supporting an older version of UWP and also the implications of targeting multiple versions.

I plan to investigate this over the next week or so in order to hopefully help us all come to a decision on whether this is something we should do. This also relates to #1684

[bijington]

Changes made in #1684 were considered safer