Removed private WeakEventListener

[puppetsw]

NetworkConnectionStateTrigger.cs had a private duplicate version of WeakEventListener. This has now been removed and uses the existing WeakEventListener in the toolkit.

Fixes

Issue #4059

PR Type

What kind of change does this PR introduce?

Bugfix

What is the current behavior?

"NetworkConnectionStateTrigger is using a private copy of WeakEventListener, it's identical to the one we already have in the Toolkit, so we should update the source to use the existing code within the Toolkit."

What is the new behavior?

"Use existing code over shadow copy."

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• New component
  • Pull Request has been submitted to the documentation repository instructions. Link:
  • Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
  • If control, added to Visual Studio Design project
• Sample in sample app has been added / updated (for bug fixes / features)
  • Icon has been created (if new sample) following the Thumbnail Style Guide and templates
• New major technical changes in the toolkit have or will be added to the Wiki e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
• Tests for the changes have been added (for bug fixes / features) (if applicable)
• Header has been added to all new source files (run build/UpdateHeaders.bat)
• Contains NO breaking changes

Other information

[ghost]

Thanks puppetsw for opening a Pull Request! The reviewers will test the PR and highlight if there is any conflict or changes required. If the PR is approved we will proceed to merge the pull request 🙌

[michael-hawker]

Think this approach is still capturing the object.

[michael-hawker]

This should just be NetworkInformation.NetworkStatusChanged += _weakEvent.OnEvent - otherwise we capture the event and defeat the purpose of the WeakEventListener, no?

I wonder if we need to look at the history, the original developer probably had the copy because of the strange delegate from NetworkStatusChanged... Trying to think of how we can work around this...

[Arlodotexe]

NetworkInformation.NetworkStatusChanged += _weakEvent.OnEvent isn't possible because NetworkInformation.NetworkStatusChanged is a custom delgate, not a normal event handler.

We can probably use the sender to access fields on NetworkConnectionStateTrigger and make this method static, that might help?

[Arlodotexe]

@puppetsw Let's do the same thing for the OnDetachAction if we can.

[puppetsw]

@Arlodotexe I'm sorry, but I'm not sure how to go about this, or I'm not understanding. If you could give a pointer I'm happy to make the change.

[Arlodotexe]

Dug into this a bit. Looks like OnDetachAction doesn't supply the access to the instance inside the delegate. Though it does null out the OnDetachAction after invoking it, so it should release the delegate and all references captured by it.

@michael-hawker does that sound right? Should be able to move forward if so.

[ghost]

This PR has been marked as "needs attention 👋" and awaiting a response from the team.

[Arlodotexe]

Copied from the original issue:

While closing #4450, we noticed that the code is not identical to what we have in the toolkit. It removes TEventArgs to allow us to do NetworkInformation.NetworkStatusChanged += weakEvent.OnEvent;.

After discussing with @michael-hawker, we won't be removing the private event listener for now. Instead, we'll use the more flexible CommunityToolkit/dotnet#404 when it arrives.