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Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

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Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#11

Post by danielhooper »

king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

I recently worked on an app that adopted a similar framework (ReSwift) and I hated it for the same reasons you are skeptical. It was needlessly complex, horrible to try and debug, and was incompatible with the "status-quo" of standard app development practices.

At the end of the day it was just a bad replacement for Core Data / Realm / whatever.

I wish I could tell you more but like yourself I really had absolutely no idea what the point was or what it was supposed to make easier.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#12

Post by lucaquerella »

lisardo wrote: post #9
lucaquerella wrote: post #3

I'm one of the author of the framework :) please let me know if you like our approach to apps development we internally use it for creating our own apps at Bending Spoons ( http://bendingspoons.com )

This is great! Is there a way to use with an existing project?

Yes, absolutely. You can use it to implement a single view or the entire app. Just render a NodeDescription in an existing UIView.

EDIT: https://gist.github.com/lucaquerella/74d8bbb5855f26249a27b4a...

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#13

Post by lucaquerella »

king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

It may be an overkill for super simple apps with just few views. But it works great with a larger codebase, at least for us. We have apps built with it with hundreds of views and it works great, it has halved our development time and helped us to have a more structured and clean approach to the state management.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#14

Post by king_magic »

lucaquerella wrote: post #13
king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

It may be an overkill for super simple apps with just few views. But it works great with a larger codebase, at least for us. We have apps built with it with hundreds of views and it works great, it has halved our development time and helped us to have a more structured and clean approach to the state management.

How do you know it halved your development time? Do you have metrics from projects executed using standard iOS conventions vs. projects using the Katana approach? Or, asked another way, what - specifically - about this approach halved your development time?

In my experience, state management hasn't really been a bottleneck in iOS development, at least not to the point where it could account for half the effort of a project (or even 25%), and I've worked on some monster iOS apps.

Forgive me for being skeptical here, but I think this is one of those extraordinary claims requires extraordinary evidence situations. "It works great" sounds great and all, but I'd have a hard time convincing a dev team to adopt an approach because someone says it works great :)

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#15

Post by lisardo »

king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

What are the normal iOS conventions?

MVC pattern in iOS usually creates Massive View Controllers that are really hard to maintain and test.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#16

Post by king_magic »

lisardo wrote: post #15
king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

What are the normal iOS conventions? MVC pattern in iOS usually creates Massive View Controllers that are really hard to maintain and test.

I'd argue that "massive view controllers" aren't "normal", and if you find yourself in situations with massive view controllers, those are likely excellent candidates to refactor into smaller view controllers that can be composed together using something like iOS view controller containment. Well-disciplined iOS developers can keep this under control.

I'll turn the question around - don't you see the potential for the same kinds of poor development practices that lead to "massive view controllers" to be just as prevalent with an approach like Katana? So far, I see nothing in Katana that will prevent poor developer discipline.

So - (and I say this mostly in jest) - if you have poorly disciplined developers, now, with Katana, you have two problems: 1) the same kinds of code quality issue that you'd have without Katana, with 2) the added downside of no one understanding yet another overly complex application framework.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#17

Post by mahyarm »

king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

I think a big problem in standard iOS land is not doing shit on the main thread. It's too easy and after a while you accumulate small bits of main thread cruft, especially as your team / code size grows bigger.

It's a similar problem that AsyncDisplayKit was trying to solve, who's ideas later moved into the react world in general.

Another general design problem in iOS land is the MVC (massive view controller). View controllers tend to get huge as time goes on and become large 5000 line god objects that do everything. A general structure that encourages you to separate things out helps in avoiding this.

There is also a general trend of dependency management being singleton sharedInstance objects everywhere, which can make unit testing a pain. Especially in swift land today with it's lack of dyanmic mocking with OCMock.

Also I notice a general lack of unit / integration testing in mobile apps.

Another one is autolayout being a layout system that crashes your app. It doesn't let you recover in a more elegant way.

---

Now it's totally possible to avoid these caveats with skill, but the architecture of things in iOS land tends to land you into these problems naturally as your team and code size grows bigger. I don't know if react's architecture solves some of this, but those are general problems with standard iOS conventions I've noticed over 7 years with iOS dev.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#18

Post by wvenable »

lisardo wrote: post #15
king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

What are the normal iOS conventions? MVC pattern in iOS usually creates Massive View Controllers that are really hard to maintain and test.

This seems like a reinvention of MVC -- your view is supposed to render your model (the state) and the controller is supposed to act on the model (actions).

The web complicates MVC but in standard desktop/mobile apps MVC is pretty straight forward.

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#19

Post by lucaquerella »

king_magic wrote: post #14
lucaquerella wrote: post #13

Earlier quoted context omitted.

It may be an overkill for super simple apps with just few views. But it works great with a larger codebase, at least for us. We have apps built with it with hundreds of views and it works great, it has halved our development time and helped us to have a more structured and clean approach to the state management.

How do you know it halved your development time? Do you have metrics from projects executed using standard iOS conventions vs. projects using the Katana approach? Or, asked another way, what - specifically - about this approach halved your development time? In my experience, state management hasn't really been a bottleneck in iOS development, at least not to the point where it could account for half the effort of a p…

I don't blame you for being skeptical.

The main advantages we've noticed using this pattern are:

1) every time there is a crash or a problem we can look at the the state and the actions that lead to that situation. This improved our ability to spot and fix bugs.

2) we can easly reproduce any appearance of the UI by providing a struct the rappresents the state of the app. This has improved our ability to QA the entire UI quickly.

3) with this architeture we've been able to refactor the code in simpler unit of logic rather then creating big VC. This has improved the readibility of our codebase.

4) it's easier to reason about the UI with the Katana (that is, declarative) approach rather than having to handle mutations

I'm not saying this is a solution for every problem but I can tell you that we internally used it and liked a lot so we felt like sharing our work with the world :)

Re: Katana – Modern Swift framework for creating iOS apps, inspired by React/Redux

#20

Post by mahyarm »

danielhooper wrote: post #11
king_magic wrote: post #8

This feels a bit like a solution without a problem, or maybe more like a giant sledgehammer-sized solution to 10 or 15 smaller ant-size problems. I guess I'm just not sure what advantage I'd get by taking a (frankly) mind-bending approach to building an iOS app instead of following normal iOS conventions. And just to be clear I've done React development on the web, and I've thoroughly enjoyed it. Modern web developme…

I recently worked on an app that adopted a similar framework (ReSwift) and I hated it for the same reasons you are skeptical. It was needlessly complex, horrible to try and debug, and was incompatible with the "status-quo" of standard app development practices. At the end of the day it was just a bad replacement for Core Data / Realm / whatever. I wish I could tell you more but like yourself I really had absolutely n…

RxSwift are super callback objects. I don't know why you would compare it with storage libraries.
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