MADDY MONTAQUILA:
Hi everybody. Thank you for joining my Microsoft build
on-demand session, upgrading your Xamarin
apps to.NET MAUI. I am Maddy Montaquila,. Am a product manager
on the.NET MAUI team, and I'm here to give you
some tips and tricks quickly about what to do
before you upgrade your app, and then show you about
the upgrade assistant tool we have in visual studio and on the command line
that can help get your migrations and
upgrades going smoothly. Let's talk about what.NET MAUI is quickly if
you are new to it. It is cross-platform native UI. The biggest change from Xamarin. If you're a Xamarin developer, you will get what I mean, and if you're not, that's fine. You don't have to
worry about it. We actually use by
default a single project, so you'll hear me talk about the single project architecture, migrating things
from head projects into a single project. That means taking the
previous Xamarin Android, Xamarin iOS apps and putting
them on one project. You don't have to, you can. That's one of the great
benefits of MAUI though. From that single project, you can deploy to all of the different places you
deployed for Xamarin, but also including
WinUI and Mac. You can do Android, iOS, Mac, and WinUI Windows apps. It is general availability
as of build last year, so we are now a year old.
We're really excited. We've come a long way from
just in the past year, especially when it comes to ecosystem readiness
for migrations. We're really excited to
share this with you. If you go to the
longer build session about.NET MAUI in general, you'll hear some stories about customers who are already
shipping MAUI apps. But this is all
lightening demo and I'm already rambling too much, so
we're going to keep going. But really.NET MAUI is just a really productive way to great your native apps
for any platform. Why should you upgrade? If you're on Xamarin
or Xamarin Forms, you might be wondering
why you have to do anywhere even though
it's not so much work. But why you have to do any work to just keep your app running? First and foremost, if you're not pushing updates to your app, you don't actually
have to do anything. At some point it
will fall out of support with iOS or Android. They will ask you to rebuild it, compile it against latest
operating systems, but you have many years
before that'll be an issue. So if you're not
doing anything to your apps, don't
stress out about it. If you are putting feature
updates to your app, we think that actually migrating to.NET MAUI
is going to end up being a really good
feature update for you and your customers
for a ton of reasons. One is just the performance, and a lot of that comes from decoupling the
platform controls from cross-platform
controls which means that instead of every function, every MAUI button
being really tightly coupled to the
Android buttons on iOS buttons and Windows buttons, we make that more flexible. By default it is, but you can
extend those, modify them. It's a faster architecture, and it will also let you develop an alternate app models if that's something you're
interested in doing. We also have a lot
better desktop support, so multi-windowing, pointer, click, gestures, all
of that great work. Ton of other stuff
on this slide. You can pause this
video and read it more deeply if
you're interested, but I'm not going to go into
it for the sake of time. One thing I wanted to show is this quick performance video. We are seeing incredibly
great startup time changes between MAUI and Xamarin. This is a MAUI app file new versus the Xamarin
Forms file new. It's almost 35 percent
faster in startup, which is pretty significant. A really heavy
real-world app we're seeing the startup time
is still under a second, which is an awesome
startup time, generally anything
under a second we're pretty happy with. Performance is a
really good thing , all customers love it. That's part of the reason we
suggest upgrading to MAUI. Do you need to rewrite your
absolute leverage MAUI? No. We'll talk about
how you can do it in your existing code base shortly. What happens to Xamarin
Android and Xamarin iOS? If you wrote something that
doesn't have Xamarin Forms, then you might not want
cross-platform UI with MAUI. That's okay. We just have.NET for Android and.NET for iOS. It's really not a features. It's just like.NET can
target those platforms. Those things will upgrade
and work perfectly fine. When should you start
trying to upgrade? The Xamarin end of
life is May 2024, which is a year from now
from Microsoft Build 2023. Like I said earlier, if you're not rebuilding or
pushing updates to your app, the store will still
accept it for a while. New apps have to be compiled for Apple against
the latest iOS. If you're building
something new, you should probably try to ship it with MAUI right off the bat. But other than that, you
should get up-to-date. You should try and make
sure that you're out of old Xamarin Forms
three dot something and relatively modern with
the code you're pushing, start valuing your
migration so that within the next year you
can go ahead and complete it and ship
it to your customers. The thing about all
of these upgrades is that every customer is
different and you know your app and your customers and your busy season or risk season, all of those things,
you know them best, so we wanted to make this
really flexible for you. Some of my tips and tricks. Couple things, again, pause and screenshot if you're interested in going
into this deeper. But I think the most important
things for you to do are get rid of
anything unnecessary. We've shipped a ton
of new controls and properties in both
Xamarin and MAUI. Some of your customer renderers you wrote back in the day, you might not even need anymore. You might as well just
get rid of those. Also inventory your
NuGet packages. If there are packages that you really depend on that
are core to your app, you should really check if they have a MAUI compatible version. If they will need to be
recompiled for MAUI, if there are alternatives,
you can switch out to. I have more info on
that on the next slide. Do not panic, and that is my number
1 piece of advice. Don't just stop working
on your app until you migrate because
you're worried about it. That's never good. I have an email at
the end, you can reach out to us
with questions too. Little bit more about the
NuGet packages and libraries. Great news is that non-UI
specific packages will not have to be recompiled if they're built off
of.NET standard, except Xamarin, iOS-specific
ones need to be recompiled. There was a minor change, but that should be
really easy to do. You are also able to just fork libraries and do that
yourself if necessary. Libraries that have
UI components. Something like extending
frames or whatever, those library owners
will have to update the namespaces and do
MAUI compatibility work, make sure that their
layouts are tested. Almost all of the popular
control vendors have MAUI capable things
out in the world now. Again, that's another
thing we have more details on in the broader MAUI session. But definitely check that out. Again, if the UI component
you're using is open-source, you can just fork
it and recompile it if necessary if the
maintainer won't do it. But this is probably the biggest upgrade
blocker when it comes to preparing to actually
to your upgrade. I always say start
your inventory, get your Excel spreadsheets
or whatever it is going, and that's a really
good place to start. Let's look at how
you can use the.NET upgrade assistant
in Visual Studio to jumpstart and really make
your life easier when it comes to getting
things over to MAUI. I'm going to open Visual Studio. This is a Xamarin Forms up. This is an app
I've worked on for a very long time as for demos. It's actually
relatively out-of-date. I have not updated it to any of the most recent Xamarin
Forms five service releases. It is called PlantLady. It tells you when to
water your plants. There's not much going on in it. Again, like I said earlier, and I will say probably
three more times, you know your app,
your codebase, your product best, so this might not
look exactly like. In fact, it probably
does not look exactly like your app
and your product. I'm just giving you
the broad strokes for you to go in and fill in the
gaps with your knowledge. Let's talk about this
upgrade assistant. This is a separate extension I downloaded into Visual Studio. If I go to Install, I have this.NET upgrade
assistant here. That's it. Very cool. I start share online,
downloaded it, set it up, good to go. What that does is when I
right-click on a project, it gives me this upgrade option. Right here I right-clicked
on my Android head project, so that's the Android-specific Xamarin Forms project
and I clicked "Upgrade", and that's what gives
me this UI here. There's also a
command line version. It has slightly
different features. If you are on Mac, you can use the command
line because this doesn't exist for Visual
Studio or for Mac right now. Cool. What this supports
is Android and iOS migrations because UWP is not the backend for Windows
for MAUI, WinUI is. That's a separate whole thing. We'll talk about
that another time. I can just download this
project and not worry about it. But there are a ton
of different ways you can go about doing
your migration. First and foremost, you want to start with
your head projects. They reference the Xamarin.Forms projects. Let me zoom in here. Your head projects S1, Android, iOS. You want to start
with migrating these, and then you want to
migrate your MAUI one. Your Xamarin.Forms
one to MAUI last. But when you right-click
"Upgrade," it gives you two options, in-place
or side-by-side. If you want to maintain
head projects, I would recommend in-place. For this Android app, I'll click "In-place
Project Upgrade." You can pick the.NET
you want to upgrade to, I'm going to go with.NET 7 because I'm cool,
I'm on the edge. Then you can actually
go in and select the individual components
you want to upgrade. If I didn't want to move
over any of my resources, if I was going to move
over to the way that MAUI does images which is all in this single project, I
can just uncheck that. Otherwise, I can just migrate
it all. Upgrade selection. Upgrade is the
word, not migrate. I'm sorry. You'll see it checks all these
things off as it goes. That was super fast, anytime you make
project file changes, it is going to unload and reload things in the solution explorer, so that's why you
see any flashing or anything happen there. But at the end of
this whole process, it shows me everything that's been upgraded and the things that it checked that don't
actually need to be upgraded, for example, all
of these images. Then I can go ahead and
I can do the same thing to my Xamarin.Forms app, I'm not going to do the iOS
one for the sake of time. This is another place where
you can get interesting. You can do the in-place
project upgrade, upgrade the same
thing, in-place. One thing that I've seen a lot
of customers like to do is actually use the side-by-side
project upgrade, which lets you move it all
into a new MAUI project. If you decide that
you at some point want to start using the
single project architecture, this is one of the
best ways to do it, I think. You can do this. You can create a new project
or an existing project, I would create a
file new MAUI app, and name it what you
want to name it and migrate into the
existing project. But for this, we'll just do new, and then PlantLady
MAUI. Right next. Pick the.NET I want, and then I tell it again
what to upgrade in. I want everything from
my Xamarin.Forms app. I will do that, it will load, show the same stuff it
showed for Android, we'll give it a few seconds. Check, superfast, and then I will have a
MAUI app at the end, I will have a new
project in the solution, that is a.NET MAUI app, where it took the code
from my Xamarin.Forms app, and moved it into the
different project. This will go and create a new project for me and
do all the same types of transformation steps it did
with the Android project, including it will take any NuGet packages and update them to the
MAUI-related ones, when it comes to Xamarin.Forms,
Xamarin Essentials. It will also go
into my XAML files, my C# files, and transform namespaces from anything that says Xamarin
or Xamarin.Forms to MAUI. It will fix certain API changes, we call them transformations. There are a bunch
of details you can get in the output pane here, from upgrade assistant, so we'll see it adding
[inaudible] statements, Microsoft MAUI down here, adding Microsoft MAUI controls
to the file so you can go in and see exactly what
it's doing to your project. Then you're left with
that project at the end, sometimes you do
have to go ahead and reload your solution explorer. What we'll do is we'll do this
to show the new projects. We'll go in a folder view, and we'll see we
now have PlantLady MAUI and PlantLady.Android, the updated one are in here. This is just a MAUI app, what's great is I can go and add a folder to PlantLady MAUI. I can call it platforms, and I can start copy-pasting
over things from my Android and iOS apps
that I've migrated, and start to use that to get the single project architecture
that we love with MAUI. If you don't want do that
though, that's totally fine. If I were to build
this right now, there probably would
be a couple of errors. That's because we don't do everything for you with
upgrade assistant, we get you most
of the way there. What I recommend is
just building your app, seeing what errors, fixing those things, and
trying to build again. It's an iterative process, what's great about this
upgrade assistant tool is that because
it's an extension, we can ship updates
to it all the time. As we identify really popular transformations
people are doing, we will push updates. To download the upgrade
assistant extension, you can search in the Visual Studio
extensions or you can go to the
marketplace website, and find it. It's called
upgrade assistant. The command line upgrade
assistant that I mentioned, it's just on GitHub,
it's open source. Feel free to grab that and
follow the instructions there, that's the one that
you can use on Mac or in the command
line so if you're in different machines where you might not have a full VSID. As promised, I mentioned there will be a way to
get in touch with us. Please e-mail
maui-upgrades@Microsoft.com, with successes, trials, tribulations, any
pressing questions. Anything you want us to know. This is not an official
support alias, the PM team, there's
a handful of us. Many of us are in person
at Microsoft Build. We are going to be
monitoring this and looking for stories and critical issues, and what trends and common things people
are bringing up to you. If we don't get back
to you right away, I'm sorry, that's why. But just know that we are
reading these e-mails, and we are using that feedback
that you're ascending us to make better
product decisions, whether it's with MAUI or with the upgrade assistant,
and everything else. Thank you so much for joining. Definitely reach out to
MAUI upgrades or my e-mail maddy@Microsoft.com
with any questions, and I hope you enjoy the
rest of Build whether you're in-person or just hanging out with the
prerecords or virtual, there's a lot of amazing content from all the different
teams this year. I hope you enjoy
it and thank you.
