Where is MVU? Tired of using old and unnecessarily verbose XAML

[ziaulhasanhamim]

When the talks about MAUI started, it was heard that it would have good support for C# UI or MVU. But now there are almost zero efforts on MVU. Yeah, there is a comet. But it's not at all usable for a real application and it's not actively worked on.

I think XAML is just a waste of C# skills. You can write great UIs with exponentially less code in C#. XAML is so much verbose and very restricted. It requires a heavy setup. We can do so much more in C#. In 2023 I don't think XAML got its place in modern UI development.

XAML is unnecessarily complicated and verbose. If you want to use a type from a namespace first add xmlns. If you want to negate a boolean you have to write a whole converter class to do that. Oh, you want to get data, you have to create a view model implementing INotifyPropertyChanged, create a field for that data, then create a property, then call other notifying methods on that property, then Bind it to an element with a weird syntax, and still it would be a lot slower because it will use reflection. If you want a button click handler, you have to create a method, then create ICommand using that method, then bind it. It's just the tip of the iceberg about the verbosity of XAML. It's a nightmare to extend features in XAML whereas you can do it easily in C#. XAML feels much like magic which will harm you instead of helping you. For each view in XAML, you really need 3 files at least. Again for writing XAML you will need a visual studio. It doesn't work on vs code and doesn't work well in rider. XAML is really so much less accessible compared to C#.

As a beginner, it is so hard to learn XAML. Bindings, ViewModels, Code Behind, the weird syntax of XAML, converters, resource dictionary, etc. Whereas UIs written in code are very easy to understand and fast to work on. The best example is obviously flutter. No one even knew about dart. But flutter was so easy that most beginners preferred it. Despite of being written in a language that is rarely used, flutter is one of the most popular frameworks for Mobile development. The biggest reason for flutter's success is its ease of use. You learn the dart language you can learn to write UIs in a flutter. But if you are an expert in C# still you will need to learn a lot of things before writing apps in MAUI. Writing UIs in code is really charming. Once you use code UI XAML looks like crap. But C# still doesn't have a good framework for writing UI in code. I think most developers would prefer code UI on any day over XAML after using that.

Anyone would prefer this over that weird XAML

public class MyPage : View {
    readonly State<int> clickCount = 1;
    readonly State<string> text = "Hello World";

    public MyPage() {
        Body = () => new VStack {
            new Text (text),
            new Button("Update Text", () => state.Text = $"Click Count: {clickCount.Value++}")
        };
    }
}

After all of that MVVM and XAML are slow. You can always write more performant apps with code UI because you are using a full programming language. Bindings can be very slow and even with compiled bindings they have overheads.

As C# is being more easy and simple to use every next version, XAML and MVVM will feel more old and verbose in the future.

There are many efforts for simplifying MVVM like the community toolkit. But these are really steps in the wrong direction. Attention should be given to writing UI in C#. I know many people will recommend I take a look into C# markup but it's mostly a workaround. For proper C# UI, there should be controls written for that instead of using old XAML components.

The web part of C# has improved a lot since 2015-2016 with ASP.NET CORE. Writing web apps and APIs has become a charm in C#. But I can't say the same with the UI part. UI frameworks are just ported to the new cross-platform .NET. Still writing UI is a hazard. Why can't it be simplified?

The only way to attract beginners to MAUI is C# UI instead of XAML. Because anyone who just starting with mobile development would hate to write XAML. It's hard to learn and hard to teach.

[symbiogenesis]

To me there are different patterns for different purposes. For most general "line-of-business" apps, there just isn't that much complexity to the UI and the well-defined and well-separated structure of XAML and MVVM is perfect.

If you are dealing with certain more complex UIs for such things as building maps, complex shapes, animations, 3D interfaces, and the like, then you might feel tempted to reach for pure C#. And that is fair, although databinding and XAML are pretty powerful and can handle a surprising amount of these cases too.

It isn't really a question of how nice C# becomes to use, because this division will remain true under any circumstance. XAML can be thought of as a Domain-Specific Language (DSL). It is perfect for doing what it does. Just like HTML or regex or SQL or JSONPath or XSLT or whatever.

Intermixing presentation layer concerns and business layer concerns is what MVVM is trying to prevent, and UIs as code make that intermixing too tempting.

Also markup languages give a much better sense at a glance what the visual output will be, and allow for more specialization and division of labor in team environments.

Microsoft's Blend tool was amazing for constructing XAML with advanced animations and such, and if you had graphics people using Blend and devs using VS or VSCode then you have a perfect division of labor.

[symbiogenesis]

You can create specialized bindings, and MAUI already has specialized bindings for OnPlatform, AppThemeBinding, and so on. Those would be for the really common cases of conditionally changing things per-platform or for dark mode.

Converters are plentiful, and CommunityToolkit.Maui comes with a whole bunch of them. But you can easily write your own.

Commands bind easily, and you can attach canExecute logic to your commands to optionally activate or deactivate them right from the ViewModel very simply. Controls can be written to visually disable themselves when canExecute is false. And built-in controls, like Button, generally do.

Behaviors are for binding to events, and EventToCommandBehavior exists to bind to events that weren't set up with ICommand support.

There are also DataTemplateSelectors, which are the most advanced case. I have used those to bind heterogeneous collections to different data templates dynamically. Like a CollectionView that renders DogViews and CatViews and so on for each animal. I use that strategy for custom forms where the fields are defined as data, and the data types are also defined as data. So you need different templates in the DataTemplateSelector for each data type.

Anything else should be done in the ViewModel or business layer.

All of that is way more than enough to do anything I can reasonably think of. There are other options, but they are against the spirit of MVVM, such as CodeBehind or zBind. Both of these options would eradicate the benefits of MVVM: testability, separation of concerns, etc.

[ziaulhasanhamim]

I was hoping for this exact answer. That's why I said there are solutions. But it's about convenience. Like you can do everything in Assembly language and C but still, you have modern languages. The same way the solutions you are giving are way more complicated than they should be. That's I said you to try flutter or swift UI. Just because you and many people in C# are familiar with XAML doesn't mean It's a good way for building modern applications. Adding more and more helper packages like community toolkit wouldn't heal the pain of XAML and MVVM.

ASP.NET CORE took a major step by introducing minimal hosting and minimal API even though we had controllers. But controllers weren't perfect for building APIs.

Same way MAUI needs a step for modernizing it. XAML and MVVM were good for xamarin. But MAUI needs to bring a revolutionary change. If it can't then it will also face the downward trend of other MVVM frameworks

You can never justify writing twice as much code for no reason and making the app complex.

[saint4eva]

C# is older than XAML, strictly speaking.

XAML was released in 2008 https://en.wikipedia.org/wiki/Extensible_Application_Markup_Language

C# was released in 2000 https://en.wikipedia.org/wiki/C_Sharp_(programming_language)

But of course, even if the reverse were true, it would have no bearing on anything because newness is not an argument in favor of anything.

C# innovates and improves, while xaml has been like since inception. Xaml is quite bad anyways.

[juanyacovino77]

Mvu .net maui framework

https://github.com/adospace/reactorui-maui

[christosk92]

@symbiogenesis
You are shooting yourself in the foot big time if you choose to completely and fully abstract and separate your logic and UI. It only works for your easy demos but for real applications its just a pain.

It sounds to me like you have never build anything of complexity other than a simple UI application that can probably be made with the Chat bot.

To say that "there are ways" and then mention literally all the pain points of writing UI in XAML, just shows how ignorant you are to the problem.

[Ghevi]

I agree that Flutter way of writing UI is very nice and easy to pickup and I would like to see MVU in Maui.
The thing I missed more in Flutter is all the C# features like linq, serialization and EF Core.
But also using the Maui Community Toolkit and CommunityToolkit.Mvvm is an enjoyable experience, they have converters, attributes and more to reduce the boilerplate code.

[ziaulhasanhamim]

The thing I missed more in Flutter is all the C# features like linq, serialization and EF Core.

That's what I'm saying C# is a great language with great features to make UI Development enjoyable and easy to pickup

But also using the Maui Community Toolkit and CommunityToolkit.Mvvm is an enjoyable experience, they have converters, attributes and more to reduce the boilerplate code.

Yeah, they try to solve issues related to the verbosity of the code. I don't think it will solve the problem in large context

[saint4eva]

Maui Community Toolkit is strongly tied to MVVM pattern. For MVU app model, Comet is the best C# MVU toolkit. Another great prospect is the AlohaKit.

[ziaulhasanhamim]

Yeah I already said There is no active work on comet and mvu support in MAUI.

[saint4eva]

Indeed. And Comet MVU was the reason so many people were excited when Maui was unveiled; unfortunately, xaml cabals are everywhere.

[juanyacovino77]

Flutter like .net maui liberar

https://github.com/adospace/reactorui-maui

[danielancines]

MVVM is a pattern, if you don't want to use it, you can assign events from XAML to Code Behind like we all did in the past. XAML can be written in C# with or without Markup Extensions, you are free to choose which is the best choice for you. I have 10+ years using XAML, since Silverlight R.I.P, and for me, it's easy to learn and the productivity is great, since you are able to let your UX work on design in XAML and Styles (very similar CSS) and let your "backend" team work on ViewModels to bring functionalities to View. The patterns are the best choices to separate responsabilities and avoid coupling. I had an experience with a person that came from Delphi and doesn't live XAML and MVVM, because almost the same reasons that you describe, and I was able to show him that you can improve the development using XAML and let the code more testable using MVVM, in two weeks he learn the basics about the XAML and MVVM and loves it.

I hope that you love it too, because it's great, have a great day.

[ziaulhasanhamim]

This is a lame argument. Just because HTML and XAML both are XML-based markup languages doesn't mean they are similar. XAML is completely different, HTML is just the structure of the page that the browser parses and then renders UI accordingly, XAML is more like a restricted programming language that is compiled to IL and it directly deals with C# objects.

There can't be worst idea than being dependent on your designer. Designers can't write XAML unless they have experience in programming. Data Binding, Converters, UI differences on different platforms, etc can't be handled by a developer.

[symbiogenesis]

The designers can just ignore bindings, and leave them off. This same principle works the same in other frameworks, like a web framework. If you use an MVVM web framework like Angular or something then you can obtain the same division of labor benefits.

HTML's Web Components specification comes in very handy here, because then you can create user-defined controls just like you can in XAML. And Angular and other frameworks could consume them.

You can tell your designers to just give you HTML, and you as the developer can figure out how to add all the bindings, or encapsulate more stuff into web components.

Not having markup in MAUI is the very same question as "Should we have HTML?"

XAML to me is simply a more structured and simple HTML. HTML used to be worse, of course, and it has caught up a little bit with XAML. Web Components being a good example of that.

[ziaulhasanhamim]

You are just making illogical arguments now.

Not having markup in MAUI is the very same question as "Should we have HTML?"

No not the same. HTML doesn't work with js objects. HTML is the structure of UI. The browser parses the HTML and then renders content. Even js can't directly render anything. It can add or modify HTML. HTML is completely different.

The designers can just ignore bindings, and leave them off. This same principle works the same in other frameworks, like a web framework. If you use an MVVM web framework like Angular or something then you can obtain the same division-of-labor benefits

Yeah, angular is going down as well. In real apps, XAML wouldn't be written by designers.

[saint4eva]

The designers can just ignore bindings, and leave them off. This same principle works the same in other frameworks, like a web framework. If you use an MVVM web framework like Angular or something then you can obtain the same division of labor benefits.

Beginners write amazing and high performance apps of different types using only code - Dart for that matter. Writing apps - both the UIs and business logic - using only code provides great experience and end-to-end solution.

Mind you, hardly anyone use Blend nowadays and designers do not write xaml. If a programmer gets a design of what you want, he can use amazing controls and component in code e.g. C# to do amazing apps.

Once more, designers do not write xaml.

[ziaulhasanhamim]

Beginners write amazing and high performance apps of different types using only code - Dart for that matter. Writing apps - both the UIs and business logic - using only code provides great experience and end-to-end solution.

Yeah, simplicity and entry barrier matter. The entry barrier to XAML is so high compared to code UI.

Designers don't write XAML

[symbiogenesis]

[ziaulhasanhamim]

It's far away from actual code UI experience. With data binding using a View Model, you can't have a good development experience in Code UI

[saint4eva]

Moreover, MVU has powerful binding and grid system.

[ziaulhasanhamim]

Actually, my real question was Where is MVU? Why there are no efforts now on MVU? @drasticactions can you provide some info on that?

[akhanalcs]

Yeah, I was hoping someone like Steve would lead MAUI team to bring fresh new ideas to radically improve it.
All this building on top of buggy Xamarin shows lack of confidence.
For eg: I'd have loved to see how Steve would have approached cross platform solution, made tooling better in all platforms, better hot reload support, large unit and UI test coverage, Swift UI style UI using C#, and so on.
Making low barrier to entry is what makes a product widely used and ultimately puts it up for success.

[NonameMissingNo]

The biggest issues, is that sure, it could have been a better framework, but it would have also came out many years later, by the time that Ava, and Uno actually fixes their weaknesses, and so, it would probably have been dead on arrival.

Making everything from scratch would have taken a lot more time.
It was announced in 2020, and came out in 2022.
Would you have been okay with it coming out in 2028?

Companies (especially nowadays) need to live in the now.

[ziaulhasanhamim]

Would you have been okay with it coming out in 2028?

Yes. Till that people could keep using XF. It's better have late than having half baked

[NonameMissingNo]

Would you have been okay with it coming out in 2028?

Yes. Till that people could keep using XF. It's better have late than having half baked

The other issue with doing from scratch, is that people using XF would have had to rewrite their designs from 0.
Sure, it didn't matter for me, because I'm coming from Native Xamarin, but a lot of people have already written XF code, a lot of it.

[juanyacovino77]

Here

https://github.com/adospace/reactorui-maui

[le-nn]

I would like to introduce two amazing thirdparty projects.

1. BlazorBindings.Maui (Forked from MobileBlazorBindings)
   https://github.com/Dreamescaper/BlazorBindings.Maui

This project is forked from MobileBalzorBindings.
This project uses Razor Component instead of XAML or C# for UI.
As discussed here, The Razor syntax also realizes for the division of labor with designers and programer .
It works very well because it's a wrapper around Maui.Controls instead of Maui.Core.
I love this paradigm very much.

2. ReactorUI Maui
   https://github.com/adospace/reactorui-maui

This project is a MVU framework like flutter or React.
View syntax is only in C#.
This is a good place to migrate from Comet.

20 years ago XAML might have been advanced and made sense.
However, many GUI applications around the world, including the WEB, are shifting to MVU-style like virtual DOM (not XAML-style MVVM ).
React,Vue, Flutter,SwiftUI, Blazor, Jetpack compose, etc...
I too got tired of the verbosity of the xaml.
I'm looking forward to maintain projects like above-mentioned by Microsoft in the future !

[ziaulhasanhamim]

Yeah, I'm just amazed at his work. It's Almost bug-free. Doesn't feel like it was built by a single person

[akhanalcs]

I love both of these over MVVM. ReactorUI is very cool. Wow!
Hopefully MSFT hires him to get that sweet-sweet Component based UI into MAUI!

[saint4eva]

There is a new app UI library in C#. It is called Spice UI https://github.com/jonathanpeppers/Spice

[akhanalcs]

Spice UI looks pretty neat! I’m impressed!

[saint4eva]

Very impressive indeed. I think they should start consolidating the efforts - Comet, AlohaKit UI, Spice UI and ReactorUI

[Xyncgas]

Rather than waiting forever for microsoft to do it, maybe we should do it ourselves, some people is going to do some hard work to glue XAML and C# together, but once the job is done you can use C# entirely. The problem is who is going to pay for it. I don't really want to use flutter or pay but come on microsoft

[ziaulhasanhamim]

Some people is going to do some hard work to glue XAML and C# together

It wouldn't be great solution to just glue XAML and C# together

[saint4eva]

C# and Xaml do not belong together - talk of gluing them together. Comet, ReactorUI or Spice UI already exist. So, we should go and contribute to Comet

[ziaulhasanhamim]

ReactorUI tries to glue XAML controls to mvu style C#. Whereas comet had completely rewritten controls for mvu. That's why comet would be more sustainable in future

[saint4eva]

Yes indeed, Comet targets Maui.Core while ReactorUI builds on top Maui Controls. I still prepare Comet and its binding and Grid system and simplified syntax. I believe we should contribute to Comet.

[le-nn]

What do you think about following idea on the ASP.NET repos ?

dotnet/aspnetcore#44866

Once this idea is officially followed up by Microsoft, MVU style will be officially supported.

There are XAML fans, but there are people who tired of XAML.
Microsoft needs to take this seriously.

I'm a big fan of C#/.NET.
I would like to see non-.NET developers choose .NET over Flutter or React Native when developing Cross-Platform GUI apps.
However, XAML has various problems as discussed.
So, We need modern Cross-Platform GUI framework like Comet and Blazor suppoted officialy.

(Or does Microsoft think AIs like ChatGPT will be writing code in the future,so there will be no need for UI frameworks that everyone finds simple and human-friendly...? )

[ziaulhasanhamim]

Yeah I love that proposal. But on the web it would be harder to implement that bcz html has been the industry standard. But rather than that it would be awesome to write blazor apps with Only C# and mvu

[saint4eva]

Or Microsoft should just take Comet serious. It already has excellent binding and grid system. And it makes development using MVU pattern a breeze. It has both HGrid and VGrid that make the Grid system very powerful.

[ziaulhasanhamim]

It just needs some bug fixes and some useful components. It would be production ready after that

[saint4eva]

Yea, you are right. And moreover, the Handler pattern that core Maui is adopting now came from Comet. So, Comet has already developed excellent architecture to build robust platform and business solution.

[juanyacovino77]

ONLY C# MVU COMPONENT BASE .NET MAUI FRAMEWORK

https://github.com/adospace/reactorui-maui

[buzzware]

You were right @ziaulhasanhamim and still right near end of 2023.
A few years ago there was some hope with MAUI and Comet, but the Comet author left Microsoft and MS mobile UI has stalled for years now. There are even predictions of MAUI going under now, and MS no longer providing UI frameworks after all these attempts.
I'm about to start a new project and moving on from Xamarin Forms, I'm not sure what to use next -
probably either Uno with MVU or MAUI with XAML. This project must be C#, while my other project is Flutter plus MobX and that is so much nicer than anything in dotnet.

[Xyncgas]

Even facebook moved on to Meta then moved on to AI, Maybe microsoft is abandoning MAUI, I do sincerely encourage microsoft to leave things as they are when they no longer maintain it so we can continue to use it to write codes in xamarin / Multi-Application-UI to deploy them to app stores or as stand alone executables

[juanyacovino77]

You salvation:
https://github.com/adospace/reactorui-maui

[juanyacovino77]

The perfect solution:

https://github.com/adospace/reactorui-maui

[jonmdev]

I have no idea why anyone uses xaml unless maybe you don't know how to code c#.

C# allows you to design all your custom objects, classes behaviors, etc. and then hook them up with perfect precision.

If something isn't doing what you want you can write a new function to manage it and hook it up immediately.

I think xaml only makes sense if you are not good with code. And if you are doing a big project, probably you should try to improve your code skills rather than use xaml.

C# is a great language. Very similar to C++ but without all the pointer and reference stuff which can get confusing. I don't know what benefit there would be in anything else.

[juanyacovino77]

https://github.com/adospace/reactorui-maui

[jonmdev]

I looked at it briefly and it is interesting to me someone created that but I can't see the point. If I need something customized, I code it with C# because:

1. I have total control over it.
2. I don't have to worry about support dropping in the future.
3. I can design it exactly as I need it.
4. I can integrate it into my other click and event management systems.

I don't see what benefit there is in increasing the complexity of these systems. The more moving parts you add the more points of failure you end up with. C# is perhaps tedious for someone who just wants to bang up a system without any thought in 3 days, but if you are working on a serious project, it is the best procedure to use.

I am right now writing my own photo carousel which I will likely be done by the end of the day. I have written others before. It will integrate into the project I am doing perfectly and work as expected with the types of data I need it to.

I think if people focus on the fundamentals then having the basic core functions like Layout/Border/Image/Editor/Shadow plus C# are all you need.

Behaviors in C# now let us even avoid deriving classes in many cases.

[Xyncgas]

As a programmer you need states to manipulate in order to make the machine to do what you want, Xamarin technology isn't Turing complete, you can not manage what's on screen like you can with browser where there is a DOM you can change it and what's displayed on screen charges

If C# replaces javascript to control the UI it's not hard to see

[Xyncgas]

The customers are always right in the matters of taste
Xamarin related technology would be the ultimate form of writing UI, because it's a declarative way to do what you wanted to do, if the components provided by the framework is what you wanted which is not nowadays
Modern UI are complex and I desire the liberty to manipulate what's on screen as easy as I could manipulate the html in browser

MAUI.Blazor is so different from MAUI, it's as if you have a golang scripting engine along with JS engine in google chrome, you get to run code out of the browser and manipulate it the experience is worth checking out you get web UI
MAUI should've been Microsoft's next browser

Declaritive framework builds trust based on the type names, while Xamarin technologies has a track record of breaking that trust by having bugs which when you expect a component to work, it doesn't

[PrestigeDevop]

ugh I'm late to the party and probably wrong , but I was here when I hear about mvc and immediately thought about game engine for some reason , anyway I've ditched learning xamarin , maui forever , while I like blazormaui syntax and I think it lacks community support , I found fuseopen to be counter intuitive since I want to use blazor for js interoperability I found fuse much more compatible , additionally for web development I prefer using svelte and sveltekit ( while I still consider asp .net core for backed I think node is much more simpler for rapid prototyping ) perhaps using both at some point ? I'm integrating prisma to my stack as it's much simpler solution for working with dbs than something like entity framework