Rework Naivgation service in Gallery app

[dipeshmsft]

Description

Navigation service in WPF Gallery has become complicated and slightly confusing. We need to refactor the code to make it more readable and less coupled.

Things to keep in mind :

• Take care of not reactivating the following Accessibility issues : Fixing home menu item navigation #644 , Fixing not able to collapse an item using enter key issue. #645

[drusteeby]

@dipeshmsft Is using prism here out of the question? Instead of type it uses string. Prism 7 is still FOSS, if not the entire library we could port just the navigation service.

Last time I checked prism doesn't work with Generic Host out of the box so porting the navigation service might be a simpler solution.

https://prismlibrary.github.io/docs/xamarin-forms/navigation/navigation-basics.html

[dipeshmsft]

Is using prism here out of the question? Instead of type it uses string. Prism 7 is still FOSS, if not the entire library we could port just the navigation service.

I won't say out of question, but I am not in favor of it as the navigation doesn't need to be quiet extensive or generalized.

@drusteeby, I was thinking of using WPF's inbuilt Navigation service along with a very lightweight wrapper to serve the purpose of the application.

The main reason why we raised this issue was because, when we implemented page search textbox, there were three main compoenents playing together :

1. Text searchbox for the page
2. TreeView for the pages
3. Navigation service

In some situations, via navigation from searchbox, the event was forwarded to treeview and then we were finding that the same page was being added twice in the stack. Moreover, we needed to take care of all the events like keydown, mouse button down etc. and need to meet the accessibility requirements there.

Although WPF doesn't has a AutoSuggestBox as in case of WPF.UI or WinUI, we want a similar search box for the control pages.

That's why I am not sure if we should target this alone. It would be better to target this issue along with the control pages search simultaneously to find the best solution.

What are your views on this ?