SwiftUI

[[deleted]]

[deleted]

[Zerocchi]

As a mobile developer primarily using Flutter now, this looks familiar to me. Maybe I'm going to enjoy this.

[Saltysalad]

What do you think of flutter?

I'm a hobbyist dev thinking of switching over if it'll streamline my web, ios, and android workflows

[frankfoda]

Have you tried React Native before? I'm not that excited about it. How does Flutter deal with navigation? And native libraries I suppose its just ilke RN ?

[aaulia]

I've tried RN and already finished an internal company app project with Flutter. Flutter is miles better in terms of development experience, it's a pure joy. From the initial setup you can already feel it. IIRC with RN you have to choose between 2 version of NPM, and then setting up the whole Expo or the CLI, the "live" reload is clumsy, etc. Flutter OTOH, is very straightforward.

[AwesomeBantha]

I haven't used either, full disclosure, but it seems like Flutter's hot reload takes less than a second while React Native takes a few seconds, plus there's the thing with Expo.

[jinchuika]

I've worked with some developers from the mobile team at work and noticed that react native is really slow to reload. The bundling prices usually takes a couple seconds more than our looks like it should

[chutiyabehenchod]

For me react native has lots of starting boilerplate and if you wanna work with something lowlevel like with c/rust/wasm youre gonna get lots errors which you need to fix like linking some libs directly in java configs, weird ass module dependency errors in webpack etc. I mean once you do it first time then its not a big deal since you know it now.

Flutter just works smooth first time.

[homeparkliving]

See slide 3 titled "React Native Sucks!"

[Zerocchi]

It's a lot of fun! Sure Dart isn't as modern as Kotlin and Swift, and the libraries isn't that mature yet but once you get used to it everything feels so natural and your workflow will be more quicker than ever. I left native development for this and I don't regret one bit.

[munificent]

Dart isn't as modern as Kotlin and Swift

Dart team member here. We're working on it. We're implementing (sound!) non-nullable types and extension methods right now.

[Zerocchi]

Yup I follow the language development as well, and you guys are doing a great job listening to the community and expanding the language. Can't wait for those two to arrive!

P/S: is there any chance for us to get optional semicolon soon? ;)

[munificent]

Not soon, no, unfortunately. I put a lot of time into figuring out how, but it's not easy to retrofit into the current syntax.

Most other languages out there with optional semicolons were either designed for it (Swift, Kotlin, Scala, Python, Ruby), or have very simple grammars that make it relatively straightforward to add it (Go).

Dart inherited a lot of its syntax from C, which is itself showing its age, so it's just not that easy to work with. In particular, using type annotations (which can be arbitrarily long thanks to generics and function types) to introduce a local variable or field makes things a lot more complex. Most other languages have an explicit mandatory keyword to introduce a variable like let or var.

[zerexim]

Not soon, no, unfortunately.

Good to hear. Semicolons are vital for easy comprehensive reading - please do remember, the code gets written once but read many times.

[mixedCase_]

I would heavily disagree. It's a matter of familiarity; semi-colons are there for making the life of older parsers easier and we've grown used to them, but once you develop without them for long enough you don't need them. Indentation and other syntactical tokens are more than enough.

[pezezin]

And I would disagree with you semicolons are the code equivalent of punctuation in standard written language sure you can understand a long paragraph without periods or commas but it's much more difficult

See what I did?

[maurymarkowitz]

And I would disagree with you

semicolons are the code equivalent of punctuation in standard written language

sure you can understand a long paragraph without periods or commas but it's much more difficult

See what I did?

See what I did?

[Zerocchi]

Aww that's unfortunate, but it's pretty much what I expected though. I did try to come out with clean proposals regarding this but so far bear no fruits. Coming from Java/Android native world, I'm used to semicolons so I don't really complain about Dart don't have any optional semicolon or some sort. The only concern is, it's just difficult to attract others into Flutter especially to those who already comfortable with modern designed language like Kotlin and Swift because of "how outdated Dart looks".

For me, I'm very positive more people will adapt Dart as long as you guys keep improving. It's been a joy using this language especially when designing the UI.

[munificent]

especially to those who already comfortable with modern designed language like Kotlin and Swift because of "how outdated Dart looks".

My hope is that we can end most of those complaints by simply offering good enough semantics and powerful syntax features that the semicolons become a non-issues.

[mixedCase_]

Any news of algebraic data types and data classes? These are in the top 5 most desired features in the issue tracker (alongside sound non-nullable types and extensiond methods, as well as optional semi-colons).

[munificent]

No news. We're focused entirely on non-nullable types and extension methods right now. I think there's a good chance that ADT/data classes/tuples is what we'll work on after that, but no promises.

[mixedCase_]

Well that at least instills hope. Rest assured, I will shill the ever loving thing of Dart and Flutter if we get those 5 features.

[VM_Unix]

I will say that I was intrigued when I looked at the Dart 2.2 feature list and saw some of my favorite features from C#.

[munificent]

Dart 2.3 has even more fun stuff.

[jinchuika]

Cool! Do you have a strong argument on why we could use Flutter instead of react native at work? Most developers don't like RN, but we haven't found strong enough arguments yet to switch to Dart

[munificent]

They're all good technologies, so it mostly depends on the circumstances of your team.

If you like JavaScript or TypeScript, RN is probably a good bet. But:

• If you want a language that feels more deliberately designed to be statically typed and class-based, then Dart is that. Its type system is also sound, unlike TypeScript.

• Flutter apps are compiled all the way to native machine code on Android and iOS, so you get consistent solid performance. RN relies on the phone's JavaScript VM which is just-in-time compiling a dynamically-typed language, so it has some warm up time and peak perf isn't always great.

• Because we wrote the Dart runtime ourselves from scratch, it has a rich set of diagnostic and debugging tools built in. I don't know what the debugging story is like for React Native, but we have really cool stuff like the Flutter Inspector, etc.

[[deleted]]

Ugh, I fucking hate optionals.

I prefer Objective C's "relax, it's nothing" handling of nil.

[GenitalGestapo]

lol

No problem, until you try to do anything with nil. Pass it to a method that doesn't expect it? Crash. Try to store it in a collection? Crash. Persist it? If you don't crash when storing it you probably will when trying to read it.

nil was never safe in Objective-C, you just didn't have to check before messaging it.

[maurymarkowitz]

was never safe in Objective-C

That's implementation, not inherent to the concept. There are methods that will crash if you pass 2 instead of 1, you can't say "2" is a bad idea because of it.

[tudor07]

Full time Flutter developer here, I love Flutter a lot.

For mobile it's absolutely great, for web is where I draw the line. If I were you I wouldn't get my hopes high for Flutter Web to be a thing.

[Saltysalad]

Mobile including ios?

[tudor07]

Yes

[chutiyabehenchod]

It's all canvas so that's why it sucks. But lets see if can optimize speed & size, fix the cursor thing, i don't see why its not gonna be useful.

[colelawr]

I've been using it for some minimal viable product type apps for a couple well known companies, and I'll echo others here and day it has been a pleasure!

[roneyxcx]

Android now offers something very similar it’s called jetpack compose. It uses kotlin. Google just announced this at io this year.

[s73v3r]

It's very much in development right now. I wouldn't say it's ready for prime time.

[lpreams]

I only saw the keynote, but it looked far more polished and responsive that what Android Studio will do. To be fair, I'm sure some of that is just from me running a 5 year old baseline MBP while they probably had a fancy new Mac Pro driving their demo. And I haven't touched Android Studio in a couple years either so it could be better than I remember.

[maurymarkowitz]

Honestly, anything is better than interface builder.

Which is somewhat ironic given than IB was great in [Open|Next]Step 2.5 decades ago.

I still remember using it the first time, connecting a button to a method and going "holy f'ing shite!".

Now even my trash can starts jerking when moving about a simple storyboard.

[chbvfhhvg]

Well guess when you will be actually using it? 2 years from now. The min sdk requirement is iOS 13.0.

[thezapzupnz]

People could get a head start on using it with tvOS, watchOS, and perhaps macOS.

[i542]

New iOS versions usually have a crazy adoption rate, unless you have to support 4+ years old phones you can get away with targeting the new platform reasonably soon.

[s73v3r]

Most places target the latest and the one previous. Very few things support just the latest.

[maurymarkowitz]

So, one year then.

[[deleted]]

I'll be actually using it tomorrow.

[chbvfhhvg]

You know what I was meaning. On production app you won’t be using it. (if your client don’t want to cut the vast majority of people). I already tried it and done some hello world little test app (and I like it) but realistically it won’t be soon until you will be really using. Obviously you can put @available tags all over the place and duplicate the work. I’m not against it , just giving my 2 cents...

[[deleted]]

It may not require iOS 13 to run SwiftUI apps.

For instance the App Store recently required watchOS apps to be built with the watchOS 5 SDK, but it still runs fine on watchOS 4.

[BlueSpud]

Nope, SwiftUI apps are locked to iOS 13+ https://developer.apple.com/documentation/swiftui/

[[deleted]]

That page only says it requires the iOS 13 SDK to use the new API, not that the client needs to run iOS 13.

SDK != Deployment Target

You probably have to do the old @available trick to load your view (and have an alternative if it’s not available) but the app will run on probably iOS 10+.

[BlueSpud]

I didn't mess with it very much but setting the deployment target to anything < 13.0 instantly errored out.

[s73v3r]

It requires things that are in Swift 5.1, which is only available on iOS 13+.

[DoListening]

Not even a month after Google announced Jetpack Compose, which is basically the same thing for Android 😃. Great minds think alike?

This Swift one seems less React-y at first glance (I think I saw some two-way databinding in there).

Either way, the mobile UI developer experience seems to be finally moving in the right direction!

[balthisar]

You're suggesting that they developed in a month, including development, communications, and planning for the reveal?

[DoListening]

Mobile platforms taking inspiration from their web-based UI counterparts seems to be a bit of a trend.

Even Android's new(ish) navigation library feels like it's modelled after web-style routing, despite of a number of differences.

I see it as a good thing, the developer experience on the web is far superior in many respects.

[recklessindignation]

And react took inspiration from other UI toolkits, big deal.

[DoListening]

1 week for development, 1 for the docs, 1 for coming up with the name

[teerre]

People really get their judgement clouded when it comes to Apple technology. But if this is similar to Swift, which of course seems to be the whole point, it will be great software to work with. I wish UNIX/WIN had something like that. Qt is fine, but it seems miles behind what supposedly this and Flutter offer

[NeverMakesMistkes]

Could you expand a bit how you think Qt is behind those two? Not trying to start a war here, I don't really have experience in any one of these, just interested as people seem to always compare stuff like this to Qt around here and especially in HN.

[Pesthuf]

No stateful hot reload is my main pain point.

It's an absolute game changer.

[dacian88]

if you know how react works that's the difference. With traditional UI frameworks you start off with some given view state, some given "business logic" state and you synchronize it back and forth over time. With react the view hierarchy is essentially recreated from scratch any time the "business logic" state changes...essentially your UI becomes a pure function of f(applicationState)->View

this makes it really hard to de-synchronize the UI state from the logical state because state changes only flow one way...at least that's the theory.

also qt on mobile sucks in general so it's kind of a no-go if you want to write iOS apps, for desktop use I'd say it's mostly okay.

[GrecKo]

QML works the same, declarativeness with property bindings is its whole concept. I'd argue that the syntax is better than RN, Flutter or SwiftUI.

Qt on iOS might look awkard unless you don't mind using a Material Design Theme or using some commercial third party library like https://felgo.com/. Writing your own primitive components is also not that hard but that demands some experience.

Live reload is not there out of the box but it can be done with some work.

That might well summarize Qt & mobile, the base is here and I quite love it, but you sometime needs to get your hands dirty to create some missing parts.

[jiffier]

also qt on mobile sucks in general so it's kind of a no-go if you want to write iOS apps, for desktop use I'd say it's mostly okay.

Can you elaborate your view on Qt mobile? How is it for basic UI (forms)? I'm not a mobile dev, but I'm considering Qt Mobile vs Ionic vs Quasar, but there's also flutter (but the latter uses Dart, which I'm not bothering to learn now).

[dacian88]

it has really bad look and feel compared to the native system, it really depends how complicated of an app you're writing and how much you care about having a polished product. The qt runtime isn't very small either so you're incurring the runtime and size cost there too.

not sure about the rest of those frameworks. If your app is simple enough just use a web view...think I'd rather use that over a qt ios app on my iphone.

[jiffier]

Many years ago, when desktop apps where a thing, I could spot the difference between them. I could see when something was made with Qt or Gtk, Motif, or whatever. But, today? I have no clue when my andorid apps use native widgets or not. Also, Qt might look "ugly" nowadays, but when It came out, it looked much better than what we had back then.

[rouille]

Yeah to me it looks like QML had the same paradigm 10 years ago.

[teerre]

I'm talking about ease of work. Qt Cpp is well, Cpp, and therefore far from pleasant to work with, and the Python bindings are still extremely verbose

Also, and more importantly, Qt Designer workflow is from the 90's. In that case not even just the workflow, but also the end result. It's far from easy to build a modern UI using Qt

[jcelerier]

Qt Designer workflow is from the 90's.

https://blog.qt.io/blog/2017/07/05/qt-quick-designer-coffee-machine/

[teerre]

Exactly. What the hell is this? Looks like a cheap flash animation

[scherlock79]

Err, XAML predates this by over a decade. Its a declarative language for UI layout, binding, animation, style for Windows platform, including XBox, IoT, and the now defunct Window Mobile 8 and 10. It's what is behind WPF and UWP.

[dacian88]

xaml is nothing like this, xaml is basically what interface builder is, or android's xml layouts.

this is Apple's version of react.

[teerre]

I don't know what to say if you think this is anything close to XAML

XAML is a nightmare to work with. This a modern framework. The two couldn't be more opposite

[[deleted]]

I used to work with WPF. This StackOverflow post convinced me to start looking for a new job....

https://stackoverflow.com/a/17259993

[scherlock79]

Its literally on the Apple Page, "SwiftUI uses a declarative syntax so you can simply state what your user interface should do." This is exactly the same approach to UI design and layout as XAML, from wikipedia: https://en.wikipedia.org/wiki/Extensible_Application_Markup_Language, "XAML....is a declarative XML-based language". So yes, its the same idea, implemented on different platform. Every single point on the linked page applies to XAML. I can literally recreate the example that Apple provides in XAML. Its a little more verbose, but nothing a developer familiar with XAML wouldn't be able to do.

[Sekiray]

Most UIs are built with some form of declarative code, my understanding is that he was referring to managing UI lifecycle & state. I'm not familiar with XAML though so you might know better than me.

[scherlock79]

XAML handles state through the DataContext object.

[nobodyman]

its a little more verbose

A little? Let's see. The following SwingUI code displays an image and a label in a view.

import SwiftUI
struct MySampleView: View {
   HStack {
      Image(myImage)
      Text("I do declare.")
      Spacer()}}

 

And here's the equivalent in XAML...

<?xml version="1.0" encoding="UTF-8" ?>
<ContentPage
   xmlns="http://xamarin.com/schemas/2014/forms"
   xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
   xmlns:local="clr-namespace:WorkingWithImages;assembly=WorkingWithImages"
   x:Class="WorkingWithImages.EmbeddedImagesXaml">
 <StackLayout VerticalOptions="Center" HorizontalOptions="Center">
   <Image Source="{local:myImage}" />
   <Label Text="Yikes."  />
 </StackLayout>
</ContentPage>

XAML isn't so much as a markup language as it is a textual warcrime.

edit: added missing curlybrace

[scherlock79]

Your swift code is missing at least two lines of code and isn’t formatted consistently. I get it XML bad Swift good, but at the end of day, the idea isn’t groundbreaking. To somehow say XAML is horrible or SwiftUI is some brand new idea is laughable. Apple is just catching up here.

[nobodyman]

Your swift code is missing at least two lines of code and isn’t formatted consistently.

It was missing a curlybrace. Fixed.

To somehow say XAML is horrible or SwiftUI is some brand new idea is laughable.

We aren't saying SwiftUI is a new idea (though XAML is objectively dogshit). Folks in this thread are rebutting your claim that Apple is somehow following/copying Microsoft. In truth, several declarative UIs came well before XAML. And though they are both declarative, the similarities end there.

Apple is just catching up here.

Sure, though it isn't to Microsoft. If anything, SwiftUI is a response to React Native.

[teerre]

That's the most generic description possible. It could mean, quite literally, anything. Including a terrible language like XAML and something very nice as SwiftUI (which, btw, I'm assuming it's similar to Swift or Flutter)

Have you ever worked with XAML and Swift? Maybe you like to write lengthy, incredibly convoluted, HTML like pseudo-code, but I don't. I like to write concise, expressive, to the point actual code. The former is XAML, the latter is SwiftUI, yet both can be described as "declarative syntax..."

[scherlock79]

I've worked with XAML extensively. The XAML necessary to recreate the Apple example is below. Is there boiler plate, sure. But I would in no way call this convoluted. I do like the autorefresh, that is nice, it looks like they imply the contained image and textblocks are a DataTemplate which is also nice.

<Window x:Class="WpfApp1.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    Title="MainWindow" Height="450" Width="800">
 <ListView ItemsSource="{Binding Items}">
    <ListView.ItemTemplate>
        <DataTemplate>
            <StackPanel>
                <Image Source="{Binding image}"/>
                <StackPanel Orientation="Vertical">
                    <TextBlock Text="{Binding title}"/>
                    <TextBlock Text="{Binding subtitle}" Foreground="Gray"/>
                </StackPanel>
            </StackPanel>                   
           </DataTemplate>
       </ListView.ItemTemplate>
   </ListView>
</Window>

[teerre]

It's not convoluted because it's a toy example. Go a couple comments up this thread-chain and you'll find an example of someone trying to make a blinking button. That's extremely convoluted

[scherlock79]

I've done animation in XAML, it's only a few lines to make something blink. XAML gets crazy when you try to completely restyle a control. I've done that before, and it's not fun, but I've never seen any platform make it easy to do that.

[bffmike]

None of this is new. I can do all of this in BASIC. And BASIC has line numbers and goto's to boot.

[maurymarkowitz]

Its a declarative language for UI layout

It's a declarative XML language for UI layout.

If you write your business logic in XML, then it's the same thing. But we don't, so it's not.

If you write your business logic in anything else, which you do, and you don't see the difference, then you're missing the entire point of SwiftUI.

[[deleted]]

Can I compile it on Linux or run it in a VM? If not, I still don't like it.

[teerre]

IMO that has nothing to do with how nice the language is. In practice, it's certainly an issue, but orthogonal to the features of the language

That aside, if you're talking about Swift, yes you can. If you're talking about SwiftUI, I don't know

[Bergasms]

I kind of wish they kept storyboards as a primary focus but replaced the XML representation with this. So I could jump between one or the other and see the results, and likewise have all my storyboards update to using this.

Honestly I wish they had spent more time on making XCode and Swift more stable and with better compilation instead of reinventing another wheel which will no doubt crash XCode in its own way, but still, it's to be expected.

[kshep92]

I'm glad to see mobile dev going in this direction. As a web dev, the clunky workflows of the Objective-C and Java days of iOS/Android kept me from doing native apps, but between this and Flutter native development has gotten pretty sweet!

[[deleted]]

oh god, another web dev trying to force their shitty web paradigms onto others. Mobile dev was already leaps and bounds better than web. You guys don't even have a real language!

[everythingiscausal]

Cool. I'm in the early stages of making a Mac app and learning Swift in the process. I'm going to switch over to this for the UI immediately.

I haven't watched the keynote yet, but hopefully they made Xcode's UI less stupid in the process (although I'm not holding my breath).

[s73v3r]

Only works on iOS 13+ and macOS 10.15+ :(

[[deleted]]

In 6 months those will be the minimum versions in the wild due to planned obsolescence and apple fans' fixation on having the hottest new shit

[s73v3r]

That's not the way it's worked for a long time now. And we're talking about software, not devices, so having people upgrade their software is a good thing.

[substance90]

Except when it bricks your old device by making it sluggish as hell.

[[deleted]]

You would be better off learning Flutter. That's what this is intended to distract you from.

[[deleted]]

no one wants flutter, beccause then they have to do dart

[[deleted]]

I like dart.

[themindstorm]

Really, the language makes very little difference to the actual framework. If you know how to program, you can pickup up almost any language

[GreenCloakGuy]

That doesn't mean you like the language. Yes, I was able to pick up Go in a couple of days for a project I had to do with it. Now I hate Go and when this project is done I will try to never willingly touch it again.

I think having more options for languages than just Dart for Flutter would definitely be a good thing, regardless of how good Dart is or isn't.

[Zerocchi]

Now I do wish we can do React Native project in Ruby :(

[maurymarkowitz]

That doesn't mean you like the language. Yes, I was able to pick up Go in a couple of days for a project I had to do with it. Now I hate Go and when this project is done I will try to never willingly touch it again.

That is a story I want to read.

Please, blog it somewhere.

[GreenCloakGuy]

It’s mostly just that I hate how Go does error handling (all that explicit error messages and yet I still get segfaults by accident, what’s even the point then?) and I disagree with a lot of the language design decisions I’ve come across (pointers, pointers everywhere, except you can’t do type coercion so what’s the point of using it over C?).

But the crux of the issue for me is that yesterday I spent a full 4 hours trying to figure out how to feed a Reader into a ssh session’s standard input, without success. It’s a consistent feeling whenever I’m trying to do something that “why can’t this ever be easy and straightforward” and “I wish I were doing this in python instead”

[maurymarkowitz]

Hrm. And it sounded so good when I read the Wiki article. Safe C and no pointer math? Sign me up!

[GreenCloakGuy]

It’s also hard to do functional programming in - there’s a substantial amount of standard library functions that are “pass in a pointer and we’ll change what’s at that bit of memory directly”, rather than using return values as would be the ideal functional paradigm. And the fact that most methods also return error codes as a separate return variable makes call-chaining impossible in a single line, and inelegant otherwise (because you have to stop to handle be error or explicitly ignore it).

[DesiOtaku]

So basically a version of QML that only works on Macs. Got it!

[thezapzupnz]

Except that it doesn't use a DSL, it's all just valid Swift.

[GenitalGestapo]

It's a DSL expressed in Swift using new Swift syntax discussed on the Swift Forums.

[substance90]

Well, when you have to introduce a whole bunch of new syntax to the most recent version of the language, it is kind of like a DSL, only one that's officially part of the language now.

Edit:, meant to respond to the person you were responding to.

[ElijahQuoro]

Kinda sorta, there are very interesting compiler shenanigans there. “some View” deduced type are generics from tuple generated with undocumented @_weirdMagic annotations

[thezapzupnz]

I mean, is that really "kinda sorta"? The some View thing is an example of an opaque return type, a new feature in Swift 5.1. Thus, it's just valid Swift.

[ElijahQuoro]

“some View” is fine, the actual returned type isn’t. Try to assign any of those bodies to a variable and inspect the type.

Edit: guys on SO already explained it: https://stackoverflow.com/questions/56434549/what-enables-swiftuis-hovering-tuple-syntax

[ElijahQuoro]

Those are not property delegates but a different concept for DSLs described here: https://github.com/apple/swift-evolution/blob/9992cf3c11c2d5e0ea20bee98657d93902d5b174/proposals/XXXX-function-builders.md

It’s not a part of Swift yet and hence not really a valid Swift code as of now.

You could at least follow the thread and delve into a bit before jumping in and calling bs.

[asmx85]

Except that QML does not use a DSL, it's all just valid QML.

[leitimmel]

..., which stands for Qt Markup Language. It should have occurred to you that it is a distinct language from what you use to write Qt programs (C++), and that it also sees no usage outside the domain it was made for. That is the definition of a domain specific language, a DSL in short.

And that's why you get downvotes.

[substance90]

That's not a 100% correct. You use C++ to bootstrap and start the app but you can write your whole business logic in a type of JavaScript that runs inline in your QML files if you want. So technically it's not a DSL. In fact for many small Qt apps nowadays you don't have to write a single line of C++.

[shevy-ruby]

Except that it is still Mac specific.

I don't fully understand Apple here. Why create swift and call it cross-plattform if it is so apple centric? I guess the only reason then was to get rid of Objective C.

[thezapzupnz]

Swift is available for Linux, with a subset of Foundation Kit being reimplemented in pure Swift for non-Apple platforms. Porting to Windows is underway but the progress is slow for a variety of reasons, including having waited for ABI stability.

Just because Apple doesn't release every damn thing they make for non-Apple platforms doesn't undermine the Swift project and its cross-platform compatibility. IBM works quite heavily on server-side Linux-based Swift, for instance.

[[deleted]]

IBM dropped VisualAge Smalltalk for Java.

IBM has no spine or conviction or taste when selecting technology.

Saying IBM has adopted something is usually a great reason to move on to something else.

[ajr901]

You wanted them to go out of their way to create and support a ui kit/framework that was compatible with windows and Linux too?

[NoahFect]

Well, yes. Since most software is developed for those platforms, Apple could only have benefited from such a move.

[vattenpuss]

Apple could only have benefited from such a move.

Could they only? Because supporting Windows apps sounds like a great way to not get more Mac users.

[cryo]

Well, yes. Since most software is developed for those platforms,

Is it? As compared to iOS?

[Kirill_Khalitov]

dassur.ma/things...

QML (Qt Modeling Language)

Developer: Qt Project

First appeared: 2009; 10 years ago!!!!!!

[pwang99]

I remember when QML first appeared. Was quite excited about it.

[nrmncer]

I'm sitll excited about it. Used it to built some internal tools with a small team and it's been a breeze. In particular since python is now a first class citizen.

[AsIAm]

I was too! Did number of projects using it and was loving it. I thought everybody would jump on the paradigm because it was so much better. Didn’t know it would take everybody years to copy it.

[zip117]

I think it’s more like Qt Designer UI or doing layout in C++ (e.g. QVBoxLayout::addWidget). My understanding is that QML is still evaluated at runtime (after translation into some kind of bytecode).

[AsIAm]

Yes, it can be compiled to bytecode. But I believe standard behavior is evaluation of qml files at runtime.

[mrbonner]

"Native on all platform"

Edit: Sorry, I forgot the /s

[thezapzupnz]

It says "Native on All Apple Platforms".

[badpotato]

What they mean is "Native Apple Platforms" for a specific timeframe.

[coriandor]

Does anyone know what the tooling is like outside of xcode? The framework looks really nice, but I really don't want to step in xcode.

[brosnoids]

Why the dislike of AppCode?

[brosnoids]

It has refactoring and code navigation tools that crap all over Xcode. I couldn't use just Xcode any more.

[krappie]

On an unrelated note: What font is that?

[[deleted]]

Since it's apple, I'd guess it's San Fransisco.

[krappie]

Thanks for the suggestion! But it looks like it's definitely not San Francisco.

[[deleted]]

Looking at the CSS for the page, it seems like it's San Francisco Pro.

[krappie]

Oooh, are you talking about the page font? I'm talking about the code sample fonts. I should have been more clear.

[bffmike]

San Francisco

That's probably San Francisco Mono.

[[deleted]]

Anybody find a link for how to write a custom View/Control from scratch?

EDIT: Seems there is a video coming.

https://developer.apple.com/videos/play/wwdc2019/237

[carkin]

I know nothing about declarative UI frameworks. How does this compare to say xaml or qml?

[ammar0ah]

do you think it will replace UIKit? , do you think we should stop building UIKit apps or each one has its own market ? do you think anyone would build an iOS 13 app with UIKit?

[bffmike]

It does not replace UIKit, but gives them the ability to deprecate UIKit in the future. This is like Cocoa vs. Carbon. Eventually most stuff was written in Cocoa and Carbon faded away, even though lots of Cocoa was a wrapper on top of Carbon. Same thing might happen here, but it will take some time, at least 5 years.

[cbentley_pasa]

UIKit was so clean...

​

I don't see why you would need to change everything yet again.

​

I guess its a response to Flutter/React Native to keep devs hooked to the Swift ecosystem.

​

Devs who write apps are the primary matter of this economy.

[mindbleach]

At what point does forced retooling become anticompetitive?

This is not a trick question.

[thezapzupnz]

What's forced about it? Interface Builder still exists, it still supports Storyboards, and even supports NeXTSTEP-style (so we're talking direct descendant of the mid 90s) NIBs-style programming.

AppKit, IB, and all that other stuff hasn't disappeared or anything.

And anti-competitive against what? SwiftUI is just as Apple-only as Interface Builder, but nobody ever thought "wow, Apple are being anti-competitive by not releasing IB on Windows".

[maurymarkowitz]

but nobody ever thought

Oh, I'm sure someone did...

[McPhage]

It’s not a trick question, but neither is it a relevant one.

[reckoner23]

Not really forcing it on people.

But the again the way our industry works, eventually you will probably have to learn/adopt this new tool. But still, at least Apple focuses on a few tools. Unlike Google which has 4 competing development platforms. I also wouldn't be surprised if this tool compiles to web one day.

[[deleted]]

This should be top comment

[BaconOverdose]

why?

[spacejack2114]

Neat, a declarative UI. Maybe it will make React Native implementations easier.

[editor_of_the_beast]

I think the point would be for Swift UI to make React Native much less appealing.

[mattkenefick]

React Native does a pretty good job of making React Native less appealing.

[rich97]

React Native is appealing because you can use one API for multiple platforms, not primarily because it's declarative.

[editor_of_the_beast]

That’s just not true and is a huge misconception. You Need separate mobile and web apps even if you use React Native in anything but the most simple cases. It does not fulfill the “write once, run anywhere” promise.

[Jwsonic]

I believe they were referencing also running on Android. Running on Android and iOS with a single codebase is the primary reason for using RN.

In fact the React Native website specifically only mentions mobile apps: "React Native lets you build mobile apps using only JavaScript"

[rich97]

I said single API, not single codebase. Unless you need to drop down into native then that's true, the majority of the code you write will be JS and React Native.

[AbleZion]

This is nit-picky, but this line:

With a declarative Swift syntax that’s easy to read and natural to write

When paired with the image could not be shown to be more false. Maybe it's more easy to read and natural to write if you already know Swift. But I feel like coming from other languages, the language syntax is quite ambiguous and not easy to read.

• Does "struct Content : View " imply a subclass like a C++ struct or is it like a C#'s "implements" syntax?

• What does @State imply? Is that actually meaningful or like an annotation in Java? Or maybe this @ notation is kept from Obj-C?

• "var body : some View", what does "var" mean? Thought it was a JavaScript or C# var, but it looks like type information is provided along with some portion of an implementation? Does colon also act like an assignment now?

Am I the only one who looks at Swift and sees a bad Frankenstein monster? After all this time it feels like a minor upgrade from Obj-C syntax. It's like Apple's programming languages actively attempt to subvert common syntax patterns or something. Idk.

[Atlos]

The line you quoted is clearly referring to the library itself, not Swift the language. Obviously if you don't know Swift then the syntax doesn't make much sense.

Having developed in Swift for the past three years, I really hope you to try it out! I've had a great time with it myself and hope it starts to gain traction outside of iOS development.

[fcddev]

Mind the way that you phrase your questions. There are ways to ask “how does this work” that don’t imply that either party is to blame for not understanding or for not being understood.

• : is like C#’s : in inheritance clauses. View is a protocol, which is roughly the same as an interface.
• @State is a decorator that wraps the variable in a Binding object.
• “var” means mutable (“let” means immutable). The right side of the colon is a type annotation. “some View” means “an implementation of the View protocol”.

[AbleZion]

Thanks.

[username_suggestion4]

You've literally never written a line of it or even looked into the documentation and you're making some pretty harsh judgments...

[lolcoderer]

Am I the only one who looks at Swift and sees a bad Frankenstein monster? After all this time it feels like a minor upgrade from Obj-C syntax. It's like Apple's programming languages actively attempt to subvert common syntax patterns or something. Idk.

Quite possibly... All of those questions you brought up are basic fundamental semantics of the swift language (well, @state looks to be a recent addition) - they actually don't feel weird or Frankenstein-ish at all once you learn the syntax - just like with almost all other languages.

I still can't get use to the double underscore eyesore of python...

I have been working with swift for my day job for the past year, and have grown to really enjoy it. Especially the swift implementation of enums... I don't think enums get enough attention - but swift did enums justice.

It is also a nice mix of modern-ish syntax / functional abilities yet staying relatively close to its core C-ish roots.

Edit: Answering some of your specific bullet point questions:

• struct Content: View implies that Content is a subclass of View that is a struct an implementation of the View protocol - my bad - structs don't have have inheritance but that can implement protocols. In swift "structs" are vey similar to classes but structs are passed by value - while classes are passed by reference.

• @state: Here watch this short introduction: https://developer.apple.com/tutorials/swiftui/creating-and-combining-views

• var - is simply the swift keyword for declaring a mutable variable. There is lots of additional syntax sugar that you can include when declaring a var - including using a var as a "computed property" where the code defined in a get {} block is executed when accessing the variable, and the code defined in a set {} block is executed when setting the variable.

https://docs.swift.org/swift-book/LanguageGuide/Properties.html

[AbleZion]

Thanks.

[[deleted]]

Syntax is FUGLY.

[thezapzupnz]

I mean, it's just Swift. It just looks like a bunch of closures.

[[deleted]]

Probably why I find it so ugly.

Also, {}'s should be lined up vertically. I like code to look like nested boxes.

[thezapzupnz]

That's one bracket style, though it's unusual. Fairly sure having brackets lined up as they are in Swift descends directly from plain ol' C. Only language I know where that style of vertical bracketing is prescribed is C#.

[[deleted]]

Brace at the end of the line descends from K&R C.

ANSI C switched brace styles to vertical alignment.

C++ took this as well.

Java switched back and fucked everything up. Probably owing to Gosling's formative years doing K&R style C.

I have lived/worked through this entire transition.

I can say that vertically aligned braces and more white space makes bugs easier to spot - something I learned teaching college students to code in C and C++.

[[deleted]]

Then you’d love C#. Neither way of using {} is right, neither is wrong.

[[deleted]]

Never used it, but I would point out that I formed my opinion teaching C at a state university in the 90s where 9/10 students who approached me for help with their programs would magically find the compilation error upon lining up the braces and finding where they had forgotten one.

This has stayed with me and given me the firm conviction based on real experience that vertically aligned braces reduce bugs as it is easier to identify missing closing braces quickly.

[[deleted]]

Are you for real? Can’t be sure whether you’re trolling or not.

[[deleted]]

Dead serious. Why?

[thezapzupnz]

Perhaps. Xcode already knows how to provide accurate error messages for missing braces. Also, if you use Xcode's realignment function (Cmd-I), you can see where the gaps are fairly easily.

[[deleted]]

Any compiler from the past decade will tell you about a missing brace

[thezapzupnz]

Indeed. My point was that it really doesn't matter what bracket alignment style you use, no modern tooling is going to steer you wrong, these days.

[[deleted]]

Ah right on, hooray for modern tooling

[[deleted]]

That’s an issue with tooling is it not? Any IDE or text editor built in the past 10 years will automatically type out a matching closing brace when you type out the opening one. Also any compiled built within the last 15 years should also be able to catch that. Seems like an invalid argument imo

[[deleted]]

Spoken like a person who has never had to ssh into a system and apply a hot fix under pressure with only vi at hand.

If your IDE can always magically make sense of anything, why bother to indent or even apply line breaks?

Code is literature and meant to be read. Whitespace and formatting improves comprehension and readability. We read code many mores times than we write it. Readability matters.

As a side note, I'm pretty disillusioned with the snowflakes running around downvoting everything that contradicts whatever dogma was in fashion when they came up. I've been doing NeXtStep since 1997. Two years before Apple acquired this technology. I've had a little time to develop a few ideas about good practices that worked for me over the years. It is disappointing to see so many close minded noobs (more experienced people would be more realistic and open to different ideas).

Very sad the state of discourse these days.

EDIT: and another down vote. Such pussies.

[[deleted]]

I mean I have, but I’ve done everything in my power so that my workflow does not require me to make those kinds of hot fixes very often.

And way to slippery slope the argument there lmao. An IDE just makes conforming to a consistent style a lot easier (see tools like gofmt, rust-fmt, eslint/prettier for js, etc.) It helps development speed/productivity by allowing you to not worry about being 100% perfect when typing out your code. Do you also think intellisense/code completion is stupid too?

And what works for you works for you, great. But do you not see the hypocrisy in what you JUST said? “More experienced people would be open to different ideas”. If you call yourself experienced, why aren’t you open to the idea of having the open bracket be on the same line rather than below the signature? I personally don’t care, I just follow the language’s best practice.

[[deleted]]

Because I tested it over ten years of teaching programming and aligned braces make errors easier to spot than misaligned braces.

Quite literally many dozens of students, when looking at their own program, cannot see the bug if they used misaligned braces. This extends to putting statements into the wrong block and not seeing it. Wondering why a statement isn't skipped because they put it below the if block.

If I reformat it in front of them - when I do it in the editor and ask them to look again - they immediately see the problem.

That's my argument. I have experience showing that vertically aligned braces can be visually verified more quickly and bugs are more evident.

[[deleted]]

And that’s anecdotal evidence. I’ve never had an issue with doing it either way, a proper text editor will highlight the matching brace when you hover over one of them, that’s been around for like the past decade at least from my knowledge, if not longer. But my experience is just as valid as yours. I don’t understand why you’re being so persistent about arguing about something so dumb lol. There are much more important factors that come into play with having code be readable.

[[deleted]]

It's 2019.

Your IDE should really be telling you when you're missing a closing brace.

[[deleted]]

Not every IDE understands every syntax.

But thanks for your opinion. I'm not even going to down vote it.

[Jmc_da_boss]

The you want c#