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Recent Posts

SwiftUI Lists: Present rows of data explained with code examples

SwiftUI Lists allow you, as a developer, to present rows of data. It's one of the most commonly used elements ...
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  •  5 min read / SwiftUI

iOS App Development: How to get started?

Learning about iOS app development and related software allows you to create an app for iPhones, iPads, Apple Watch, or ...
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  •  4 min read / Swift

SwiftLee in 2024: Lessons learned and achievements

Today marks the last day of 2024 making it a perfect moment to reflect and share my learnings. You've probably ...
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  •  6 min read / General

Swift Keywords

Do you know how to use each keyword in Swift?
Click on the keyword to learn more and explore code examples.

actor associatedtype async @autoclosure available await break catch class continue defer @discardableResult @dynamicCallable @dynamicMemberLookup enum @escaping fileprivate for @globalActor guard infix isolated lazy @MainActor nonisolated optional postfix @propertyWrapper private protocol required @resultBuilder rethrows sendable some struct subscript throw throws try typealias @unchecked @unknown unowned weak where while

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Learn more about Swift

iOS App Development: How to get started?

Learning about iOS app development and related software allows you to create an app for iPhones, iPads, Apple Watch, or ...
  •  4 min read / Swift

Swift Tutorials: Learn Swift with Easy-to-Follow Code Examples

Swift tutorials help you to get started building apps for Apple's platforms. The best way to learn Swift is by ...
  •  4 min read / Swift

SF Symbol: How to for Swift & SwiftUI

Apple introduced SF Symbols during WWDC 2019 as a big present for developers, as they're straightforward and free to use ...
  •  10 min read / Swift

How do you stay current as a Swift developer?

Let me do the hard work and join 19,344 developers that stay up to date using my weekly newsletter:

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Learn SwiftUI

SwiftUI Lists: Present rows of data explained with code examples

SwiftUI Lists allow you, as a developer, to present rows of data. It's one of the most commonly used elements ...
  •  5 min read / SwiftUI

SwiftUI Button: Custom Styles, Variants, and Best Practices

SwiftUI allows you to create buttons in different styles, both custom and default configurations. You can define reusable button styles ...
  •  4 min read / SwiftUI

@Entry macro: Creating custom environment values in SwiftUI

The @Entry macro in SwiftUI allows you to define custom environment values without writing boilerplate code. While introduced in Xcode ...
  •  2 min read / SwiftUI

Build Apps Faster using RocketSim

Recommend by Apple as an “Essential Tool for Developers”, RocketSim helps thousands of engineers to save hours per week. Discover these articles and learn how you can leverage RocketSim to improve your workflow:

App Actions

App Actions Perform Menu

RocketSim Tools

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Combine all the things

@Published risks and usage explained with code examples

@Published is one of the property wrappers in SwiftUI that allows us to trigger a view redraw whenever changes occur ...
  •  4 min read / CombineSwiftUI

RunLoop.main vs DispatchQueue.main: The differences explained

RunLoop.main and DispatchQueue.main are often used as schedulers within Combine. During code reviews, I often encounter inconsistency in using one ...
  •  3 min read / Combine

PassthroughSubject vs. CurrentValueSubject explained

PassthroughSubject and CurrentValueSubject are two types from the Combine framework that conforms to the Subject protocol. Both are very similar ...
  •  4 min read / Combine

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Dive into Core Data

How to observe NSManagedObject changes in Core Data using Combine

Observing changes in Core Data NSManagedObject instances with Combine publishers can be a great solution to keep your user interface ...
  •  3 min read / CombineCore Data

Data validation on insertion, update, and deletion in Core Data

Data validation in apps is important to make sure we save data conforming to the business rules. A name should ...
  •  3 min read / Core Data

Derived Attributes to improve Core Data Fetch Performance

Derived attributes are available since iOS 13 and aim to improve fetch performance in many different scenarios. Although we have ...
  •  3 min read / Core Data

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Be an expert on Xcode

Inspect network traffic using the Xcode Simulator

Inspecting network traffic is an essential skill for app developers. Several tools allow you to monitor requests going in and ...
  •  3 min read / Xcode

Xcode Build Insights: Keep track of project compilation times

Xcode Build Insights lets you keep track of compilation times to ensure your project doesn't suddenly become slow to build ...
  •  4 min read / Xcode

Solve Missing API declaration using required reason (ITMS-91053)

Apps submitted to the App Store must define API declarations using the required reasons. Apps that don't will be rejected ...
  •  4 min read / Xcode

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Get better at debugging

Memory consumption when loading UIImage from disk

Memory consumption can quickly increase if you load many images from the disk using UIImage. You'll generally load images from ...
  •  5 min read / DebuggingSwiftUI

Debugging SwiftUI views: what caused that change?

Debugging SwiftUI views is an essential skill when writing dynamic views with several redrawing triggers. Property wrappers like @State and ...
  •  6 min read / DebuggingSwiftUI

OSLog and Unified logging as recommended by Apple

OSLog is a replacement for print, and NSLog and Apple's recommended way of logging. It has different logging levels, like ...
  •  6 min read / DebuggingWorkflow

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Improve your workflow

Designing Apps: 5 Methods to improve your workflow

Designing apps can be challenging if you don't have a design background. Many of you who read my blog are ...
  •  3 min read / Workflow

Test-Driven Development (TDD) for bug fixes in Swift

Test-driven development (TDD) is a technique that requires you first to write a failing test before you start implementing a ...
  •  4 min read / Workflow

Third-party libraries acknowledgments using a Settings bundle

Third-party libraries help developers build apps faster but often come with a license. The MIT license is likely the most ...
  •  4 min read / Workflow

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Optimize yourself and improve

Contingent pricing for in-app subscriptions

Contingent pricing for in-app subscriptions creates a new way to retain and attract customers by providing discounted subscription prices to ...
  •  4 min read / Optimization

App onboarding funnel optimization to increase conversions

An app onboarding can be seen as a funnel full of steps toward the key action of your application. A ...
  •  6 min read / Optimization

App design: 5 benefits of using system components

Building custom elements and ignoring the sometimes boring system components during app design can be appealing. However, these boring elements ...
  •  3 min read / Optimization
Explore categories Swift Combine Concurrency SwiftUI Core Data Xcode Debugging Workflow Optimization Swift Charts Swift Testing Most Popular Posts
  1. MainActor usage in Swift explained to dispatch to the main thread
  2. Async await in Swift explained with code examples
  3. Sendable and @Sendable closures explained with code examples
  4. SwiftUI Lists: Present rows of data explained with code examples
  5. Sheets in SwiftUI explained with code examples
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