[Epic] Multi-window support

[jeromelaban]

Add support for creating multiple windows in the same app, using WinUI provided APIs.

Notes

• Will require us to start utilizing SceneDelegate on iOS/MacCatalyst
  • https://stackoverflow.com/questions/58405393/appdelegate-and-scenedelegate-when-supporting-ios-12-and-13
  • https://manasaprema04.medium.com/scene-delegate-vs-appdelegate-86e22dc17fcb
  • https://medium.com/@kalyan.parise/understanding-scene-delegate-app-delegate-7503d48c5445
  • https://www.appypie.com/app-builder/scene-delegate-app-delegate-xcode-11-ios-13
  • https://www.fivestars.blog/articles/app-delegate-scene-delegate-swiftui/
  • https://www.kairadiagne.com/2019/11/18/adopting-the-new-scene-delegate
• It seems that in WinUI 3, each window is essentially a XAML Island - having DesktopWindowXamlSource at the top
• For iOS we will be able to implement ApplicationView.Title property and apply it on the ViewController/Scene
• The Window should have its Bounds initialized even in the window constructor - re-enable AssertInitialWindowSize on Skia targets

Resources

• Very useful overview of relationship between various windowing-related classes https://stackoverflow.com/questions/33680631/coreapplicationview-vs-corewindow-vs-applicationview/51585979#51585979
• Additional details on multiple views support https://learn.microsoft.com/en-us/windows/apps/design/layout/show-multiple-views

[horaciodiez]

Hi! Any updates on this? Thank you! Regards

[sasakrsmanovic]

Hi @horaciodiez - what target platforms are you most interested in?

[horaciodiez]

Hi @horaciodiez - what target platforms are you most interested in?

Hi @sasakrsmanovic ! I´m most interested in Windows (well, of course) and macOS (eventually Wasm). Having said this, you can avoid the rest of the message :)

We are planning to jump on the WinUI boat now that WinAppSDK 1.1 and MultiWindow support is released. There are a couple of new projects on the way, and the OS targets are both Windows a macOS. We can make Windows mandatory, but if we have a chance to target both it will be welcomed (and so Uno)

In Short, we decided to go to "MultiWindow" in the Desktop / Laptop - LOB Apps environment. I may write lot more about this, but i get bored to read myself.

Excuse my poor english. Thank you! Regards.

[notofug]

Hi, for Wasm builds ; could multi-window support enable the application to present different windows in unique url's at the same time? (ref also https://github.com/unoplatform/uno/issues/5656) Would it be possible to construct (manually) a HTTP-page that displays the same Wasm-instance in multiple frames, each one viewing different windows of the Wasm-app? I am wondering how to somehow enable viewing for instance http://wasmapp/status-page and http://wasmapp/config-page etc simultaneously without spawning multipleWasm-app instances in the browser .. all in same browser-tab ; would that be feasible? ;-)

[renjuashokan]

Hi, I'm also looking to port my current WPF multi-window project to "uno" to make it work on Ubuntu as well. But the lack of Window itself makes it impossible to do it. Will this feature come on anytime soon?

[FrozDark]

I don't think we see that till this year :/ Most probably end of the next year

[MartinZikmund]

@renjuashokan @FrozDark I would be more optimistic about the availability of this feature, it all depends on the demand. If it is highly requested, it will be prioritized. Our goal also is to implement it properly though - making sure it follows the WinUI implementation as closely as possible so that it is extensible for future

[wokhan]

Well, I'm also interested as I only find workarounds I'm not really happy with (using Popup outside of WinUI... as I'm trying right now to use the Window class with WPF as well but not sure it will work with your Skia implementation). I might also use a global TabView to mimick this multi-window behavior (each tab hosting the "child window" contents) but usual windows would be a way better fit as the goal is to be able to see them all at the same time...). Thanks!

[horaciodiez]

Hi. Happy 2023! Any good news about this?

[francoistanguay]

... as I'm trying right now to use the Window class with WPF as well but not sure it will work with your Skia i

Can you reiterate what platforms you're mostly interested in?

For the record, on Windows, Uno isn't present, WinUI runs natively so whatever WinUI supports you can do.

For WASM, how do you foresee Multi-Window working?

Fir macOS, it's pretty straightforward.

[wokhan]

Hi, For WinUI I've no issue of course, but for WPF/Gtk/WASM which I'm interested in, you can only have one window (the main one) which is blocking any multi window scenario. I made something pretty simple (while unfinished), Windows are not windows but simply controls loaded on top in the same window, with a fake taskbar (a stack panel where each item matches one of those "windows", allowing to hide/show opened ones). Basically popups, linked to this "taskbar". Of course it means you cant go outside the main window boundaries, but at least it works (well, partly, as I didn't finish that yet, I forgot about that while working on other subjects and still have to implement movable popups, which isn't that hard anyway).

[horaciodiez]

Yet another relsease and no news on this one. Multi platform - Mono Window. :(

[FrozDark]

I think initial support will be in a version 5

[horaciodiez]

In @MartinZikmund we trust.

[horaciodiez]

... as I'm trying right now to use the Window class with WPF as well but not sure it will work with your Skia i

Can you reiterate what platforms you're mostly interested in?

For the record, on Windows, Uno isn't present, WinUI runs natively so whatever WinUI supports you can do.

For WASM, how do you foresee Multi-Window working?

For Wasm may be something like this? 😬

[MartinZikmund]

@horaciodiez That sounds more like a "in-app window" control/docking control. Could be an interesting feature for https://github.com/unoplatform/uno.toolkit.ui

GitHub

GitHub - unoplatform/uno.toolkit.ui: A set of custom controls for the WinUI and the Uno Platform not offered out of the box by WinUI, such as Card, TabBar, NavigationBar, etc.

A set of custom controls for the WinUI and the Uno Platform not offered out of the box by WinUI, such as Card, TabBar, NavigationBar, etc. - GitHub - unoplatform/uno.toolkit.ui: A set of custom con...

[horaciodiez]

Hi @MartinZikmund ! I believe that it could be like the old MDI interface, but it will be ideal that we can drag the window "off boundaries" the "mdi" container like the sample attached. (the sample is a modal dialog, just to show the idea) Btw congratulations for the new 4.10 release! But (always a but) I still need a multi-window platform to build a proper LOB app for Windows and Mac desktop clients. 😬

[jingliancui]

Hi All, is it possible for wasm? I plan to choose wasm stack for a product, but users are from enterprise, they are used to use multi browser tabs for their daily tasks.

[jeromelaban]

@jingliancui Actual multi-window for webassembly is currently unknown as it would require multi-window shared array buffer sharing and that's not something that the .NET runtime currently supports.

It's possible to create what's been shown in https://github.com/unoplatform/uno/issues/8341#issuecomment-1710476013, though.