turing complete with a stack of 0xdeadbeef
I mostly write about Swift, Objective-C, iOS, open source, and other software development topics. Sometimes I write about the ethics of tech, labor, and politics. I also write personal essays and notes on what I'm currently reading.
I previously wrote about implementing Dark Mode in an older codebase, specifically how Dark Mode works (or doesn’t) with CGColor. I recently fixed a bug in the same project that was difficult to track down because it manifested in such a strange way. After finding the problematic code, I realized that it is an extremely common scenario in iOS codebases — so you might have this bug in your code as well!
I was recently working on a project that uses modern collection views on iOS — that is, using diffable data sources, snapshots, and cell providers. I hooked up all the components and my collection view was working, or so I thought. I started to notice some very odd, unpredictable behavior when the collection view was updated. Some of the time, the cells were updated correctly. Other times, I would see duplicates and missing data. Here’s what went wrong.
This year at WWDC, some significant improvements and changes were announced for UICollectionView and UITableView. You can watch 10252: Make blazing fast lists and collection views for all the details, but I want to highlight some of them here.
I’ve been following what’s going on with SwiftUI since it was released with iOS 13 at WWDC 2019 and have even taken extensive notes, but I have avoided using it. As I wrote before, I mainly wanted to avoid dealing with bugs and workarounds that might make me less productive compared to using UIKit, which I know quite well. I’m very interested in learning and using it, I’m just hesitant given some of Apple’s history, like early years of Swift. I have no doubt that SwiftUI will be the future of Apple platform development, the question is when that future will arrive. This year the framework is debuting its third major release in iOS 15. How far has SwiftUI come, and is it ready for building serious apps?
I recently became acquainted with The United Front Against Displacement at an event in Oakland. UFAD is an anti-gentrification organization and there is a Bay Area chapter along with chapters in a few other major cities.
I was very excited at this year’s WWDC when Apple announced DocC, their new “Documentation Compiler” tool that generates documentation from comments in your source code. Unfortunately, it’s not going to work for the majority of open source authors.
Lately I’ve been upgrading and making improvements to my website and blog. As part of that work, I was updating and refining how my RSS feed gets generated with Jekyll. And then I realized something that I had not given much thought to previously. When including the full content of blog posts in an RSS feed, if you link to other posts or pages on your site should you be using absolute URLs or are relative URLs ok?
For the past few weeks I have been debating on whether or not to distribute a new Mac app via the Mac App Store or independently. I have arrived at a crossroads in development where I need to make this decision. I am mostly code-complete for my MVP 1.0 release. The question I am facing is how I want to spend the remainder of my time to cross the finish line.
I think App Library is one of the best features added to iOS in the past few years. I’m not being sarcastic, I know some folks dislike it. However, I absolutely loathe trying to organize apps on my phone into folders, because many apps do not have a singular, definitive category.
I upgraded to Big Sur three months ago. I know I’m (fashionably?) late to this party, but here I am. This is the longest I have ever waited to upgrade macOS. It feels weird, considering WWDC is next week where we will see what is next for macOS. Big Sur still feels new to me, and announcing the next major release already feels too soon. I was avoiding Big Sur based on various reports about bugs and instability. There were not any ‘killer’ features I was eager to have, thus the main reason I upgraded was because Xcode 12.5 required it.
Previously, I wrote about Time Machine “error 45”, an obscure bug in macOS Catalina. I still have no idea what was causing backups to fail, nor what “error 45” means. However, I am happy to report that I think this issue has been fixed in Big Sur.
A few months ago, I shared my notes and resources for learning about compilers and LLVM. It turned out to be pretty popular and folks seemed to find it useful. So I decided to do it again, but this time for SwiftUI. However, unlike learning about compilers and LLVM, I am not declaring bankruptcy with learning SwiftUI. While I have still not written a single line of SwiftUI code, I know I eventually will.
Despite the fact that closures (and functions) are reference types in Swift, they cannot be compared using == or ===. But why?
One aspect of using OmniFocus involves maintaining an archive of your data (if you choose). Over time — think years of using OmniFocus as your main task management tool — your local database of projects and tasks will grow very large, because OmniFocus keeps a record of everything you have completed or dropped. You can think of it as archiving your emails instead of putting them in the trash.
Over the past few years, Apple seems increasingly willing to cooperate with authoritarian governments, uninterested in protecting its own users, and unwilling to actually standup for human rights in broad terms, as often portrayed by its marketing department or direct statements from CEO Tim Cook.
UserDefaults is one of the most misused APIs on Apple platforms. Specifically, most developers do not handle default values correctly. In fact, I have never worked on a single production codebase at a company where this was done accurately. Most libraries get it wrong, too.
Lately, it feels like every few days someone is sharing a new Xcode tip on Twitter or on their blog. They range from hidden settings to features I simply never knew about. I started saving links and planned to add a new “Xcode tips” section to my TIL repo on GitHub to reference later. But as I started, I realized that the resulting markdown file would not be easily discoverable or shareable. I thought, wouldn’t it be nice if the iOS and macOS developer community had a single place to find and share Xcode tips?
As I continue to pursue Mac app development more seriously, I can build on and borrow from my many years of iOS experience. While many aspects of writing Mac apps are very similar to iOS, or at least somewhat familiar, other aspects are quite different. One of the big differences is testing, and deciding how many versions of macOS to support.
I have a few Swift scripts to automate tedious tasks for maintaining my blog. I updated one today to use pipes. It took me a minute to figure out, because it did not feel very intuitive. I’m not sure if I feel that way because the interface is actually that clunky, or if I’m just inexperienced with Swift scripting. In any case, here’s how it works.
Xcode’s UI testing framework has had its ups and downs over the years. Most recently, it has been much more robust and reliable in my experience. However, tests still tend to flake sometimes. Here are some ways that I have been able to reduce flakiness in UI tests.
I did not expect that I would have to follow-up on yesterday’s essay so soon, but I can’t say I’m surprised. In the past 24 hours, there were two mass shootings in the US. It is shocking and horrifying, yet somehow entirely predictable.
I have been periodically deleting my tweets for a while now. Yesterday, I finally found a reliable solution for deleting my Twitter “likes” as well and I spent some time deleting all of them. Long ago, I also deleted all of my content on Facebook and Instagram. If you are interested in purging your social media accounts, here are some options.
Oakland has been anything but normal over the past year during the pandemic. But we are starting to see glimpses of normality. Little by little, the whole country is returning to “business as usual”, as they say. And the first real indication that normality is on the horizon for the US was a recent story out of Arkansas.
This post is mostly for posterity, for anyone currently experiencing these bugs on macOS, and to praise Titanium Software’s excellent Mac utility app OnyX.
The Touch Bar on my MacBook started freezing and experiencing UI glitches recently. It was completely unresponsive. At the time, the only way I knew to fix it was to reboot my entire machine, which felt ridiculous. Luckily, there is a better way.
I’ve written about my web host before. I’ve used NearlyFreeSpeech.net for years. It’s very “bare bones”, very DIY, and very no-bullshit. I highly recommend them, especially if you only need to host a static site. It is so inexpensive you could say it’s nearly free.
Earlier this year, I decided to re-implement analytics for my site after discovering a viable privacy-aware (and open-source!) alternative to the user-hostile spyware garbage that we call Google Analytics. I have really enjoyed using GoatCounter and I highly recommend it. Now that I have this data, I thought it would be fun to share my top 10 most popular posts in 2020.
Continuing my (still somewhat recent) tradition, here are the books I read in 2020. You can find previous years under the #reading-list tag. I really thought I was going to be able to read a lot more this year, but fuck this pandemic and fuck 2020 all around. There were many weeks where I simply could not focus on much of anything.
Today I cleaned up my various projects and todo’s in OmniFocus. I am always collecting links and resources for potential project ideas, or for general learning. Sometimes, however, it is best to acknowledge that I will likely never have enough free time to even begin some of these endeavors.