Support Avalonia 11

[Chaoses-Ib]

Avalonia released 11.0.0-rc1.1 2 weeks ago, but it seems that Avalonia.ExtendedTool doesn't support it yet:

Is it possible to add support for Avalonia 11?

[Yusuke1998]

Hello, this update would be interesting, I try to do it on my own, but it is a lot of work and even more so without fully knowing the logic or initial basis, it would be good to provide support. thank you so much

[stackdamage]

It will be very useful and helpful if Avalonia.ExtendedToolkit supports Avalonia 11, especially for thoese guys who is familiar with WPF WPF extended toolkit.

[Wowhere]

I`am currently trying to rewrite code to Avalonia 11 but it is much harder than i thought https://github.com/Wowhere/Avalonia.ExtendedToolkit. Contributions are welcome

[Yusuke1998]

@Wowhere I was trying, but gave up when I couldn't resolve the errors with IItemContainerGenerator among others, I'm pretty new with c# and avalonia in general. Likewise, if there is anything I can help with, I'll join in. Greetings and good luck.

[Wowhere]

@Yusuke1998
Things to do:

Fix themes management (replace "XamlColorSchemeGenerator" dependency) and re-implement themes changes.
Controls Extensions re-implementation (KeyExt etc).
Fixing View code - what to do with "ItemTemplate" removed in Avalonia 11???
Controls fix - fix ItemContainer methods, removed in Avalonia 11 and other staff.

[Wowhere]

I made quite a big progress in supporting Avalonia 11 in my fork, if anyone want to help fix controls, contributions are welcome