If you work on a Swift project that follows the Model-View-ViewModel (MVVM) architecture or similar, you may want to jump to counterpart in Xcode from your view to your model, and then to your view model. (ie. by using Ctrl+Cmd+Up and Ctrl+Cmd+Down).
You can do this in recent versions of Xcode by setting a configuration default.
From a terminal, just type this command and press Enter:
defaults write com.apple.dt.Xcode IDEAdditionalCounterpartSuffixes -array-add "ViewModel" "View"
| # Install Pods and use `--repo-update` if needed (might need to add sudo for the gem command below) | |
| set -e | |
| if [ -f "./Podfile" ] && [ ! -d "./Pods" ]; then | |
| echo "Podfile found and Pods are not checked-in to git; installing Pods" | |
| if [ -f "./Podfile.lock" ]; then | |
| current_version=`pod --version | xargs echo -n` | |
| podfile_version=`cat Podfile.lock | grep -E 'COCOAPODS: \d(\.\d)*' | sed -E 's/COCOAPODS: (.*)/\1/' | xargs echo -n` | |
| if [ "$current_version" != podfile_version ]; then | |
| echo "Cocoapods version $current_version doesn't match the Podfile.lock version $podfile_version, installing Podfile.lock version" |
An Xcode project generates the following archive:
$ tree Yams-macosx.xcarchive
Yams-macosx.xcarchive
├── Info.plist
├── Products
│ └── Library
│ └── Frameworks
│ └── Yams.framework
| /** | |
| * MacEditorTextView | |
| * Copyright (c) Thiago Holanda 2020-2021 | |
| * https://bsky.app/profile/tholanda.com | |
| * | |
| * (the twitter account is now deleted, please, do not try to reach me there) | |
| * https://twitter.com/tholanda | |
| * | |
| * MIT license | |
| */ |
The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).
My take-aways are:
You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.
Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse
| ===-------------------------------------------------------------------------=== | |
| Swift compilation | |
| ===-------------------------------------------------------------------------=== | |
| Total Execution Time: 0.0307 seconds (0.1196 wall clock) | |
| ---User Time--- --System Time-- --User+System-- ---Wall Time--- --- Name --- | |
| 0.0043 ( 39.3%) 0.0091 ( 45.6%) 0.0133 ( 43.4%) 0.0547 ( 45.7%) performSema | |
| 0.0030 ( 27.5%) 0.0070 ( 35.2%) 0.0100 ( 32.5%) 0.0437 ( 36.5%) performSema-loadStdlib | |
| 0.0011 ( 10.0%) 0.0011 ( 5.4%) 0.0022 ( 7.0%) 0.0081 ( 6.7%) performSema-parseAndCheckTypes | |
| 0.0008 ( 7.0%) 0.0009 ( 4.4%) 0.0016 ( 5.3%) 0.0067 ( 5.6%) Type checking / Semantic analysis |
Apple will reject apps that are using private url schemes (Ugh, Apple....) if they are pretty much obvius. Some apps are rejected and others are not, so, be aware of this issue before implementing any of those URL's in your app as a feature.
| import Foundation | |
| /* | |
| This is used by NSNotification.Name to allow enum-like members, | |
| but where new members can be added in an extension! | |
| enum Directions: String { | |
| case north = "North" | |
| } | |
| ACTION | |
| AD_HOC_CODE_SIGNING_ALLOWED | |
| ALTERNATE_GROUP | |
| ALTERNATE_MODE | |
| ALTERNATE_OWNER | |
| ALWAYS_SEARCH_USER_PATHS | |
| ALWAYS_USE_SEPARATE_HEADERMAPS | |
| APPLE_INTERNAL_DEVELOPER_DIR | |
| APPLE_INTERNAL_DIR | |
| APPLE_INTERNAL_DOCUMENTATION_DIR |