Swift

A collection of 64 posts

SwiftUI

Adding Shadows to SwiftUI views

Among many things, SwiftUI provides an easy way to add shadows to view with a few lines of code. In today's post, we will see how to add a background shadow to any view in any direction in SwiftUI. To add a background shadow, we will use the background API

ARC

Deep dive into Swift memory management with ARC

It's been a while since my last post. For past few months I was busy with work, personal life and lot of things happening outside it so couldn't really commit to writing another article. However, I am back now and going to write about Swift and its memory management quirks.

iOS

iOS - Creating Programmatic Layout without using Storyboard (Swift/Objective-C)

There are two ways of creating layout on iOS. First, using readymade storyboard provided by Xcode when you create a new project. And second, by manually creating a UIViewController subclass and assigning it to UIWindow object as a rootViewController in AppDelegate class. However, things have changed since Xcode 11 and

iOS

Drag and Drop on iOS using Swift

Hello folks, it's been a while since I wrote my last article. Today we're going to learn how to implement drag and drop feature on iOS using Swift. To see in advance what we're going to achieve by the end of this tutorial, please watch the following video, > To summarize

UICollectionView

Tutorial - Creating Programmatic UICollectionView in Swift

Creating a UICollectionView could be stressful - As compared to dealing with UITableView. But things don't have to be this way for so long. Every time I have to add a CollectionView in the app, I end up spending long time trying to figure out what did I do last

Swift

Using Codable Protocol in Swift 4.1

Swift 4 Codable protocol to decode and encode json data and model objects. Explained with examples.

UITableView

Add headers and footers to tableview sections

> In the previous post [https://jayeshkawli.ghost.io/add-header-footer-view-tableview/], we saw how to add header and footer views to entire table view. In this post, we will see how to add header and footers to individual UITableView sections Before we get started, make sure (Either programmatically or through storyboard) to

Xcode

Xcode symbolic breakpoints - Break at method call

Today I am going to write about the big advanced debugging feature of LLDB. I am calling it advanced because I myself didn't know about it for a long time. It allows you to add a symbolic breakpoint which will halt the execution at a specific point so that you

Async

Understanding the async behavior

Handling async behavior is tricky. I was caught into same gotcha when I first started dealing with async code few years back. It's useful behavior in most of the programming applications, especially when we're dealing with heavy or network-based operation. So you cannot really escape from it, so why not

yyyy

Challenges of DateFormatters

Working with DateFormatters is tough - At least on iOS. Today I will show with an example how I shot myself in the foot while working with simple DateFormatters problem. Here's the problem statement: I had an UI where user would choose month and year through a simple picker and

Minesweeper

Rewriting a Minesweeper - Part 3

Welcome to part 3 of the Minesweeper game. Today we will see logic behind some of the core and bonus features in the game. Highlighting tiles Tiles highlighting is triggered when user taps on one of the tiles which is not mine. This triggers a sort of chain reaction to

Minesweeper

Rewriting a Minesweeper - Part 2

Happy new year to all. I guess as I am getting old, I am not feeling enthusiastic enough about new years. There is one thing I am excited about though. Writing a rewriting Minesweeper game in Swift. Yesterday was quite a productive day in terms of my progress. Here's the

Minesweeper

Rewriting a Minesweeper - Part 1

I am going to being this series of post on how I found my 4 year old Minesweeper game project written in Objective-C and process to start converting it into Swift. My goals for this project are as follows: 1. Make sure to bring this project in stable state -

iOS

How to get the iOS App Metadata in Swift

Working on a new app could be exciting. However, there are certain things or information which you might want to get as a part of the core feature. One of them is the app metadata. This may contain numerous values - Some of them essential some - not so useful.

Swift

When to weakify

Today I am going to talk about one of the discussion prone topics on iOS platforms. Detecting memory leaks and when to apply weakify. The topic came up while I was recently performing a code review and there were some discussions on whether there is a memory leak or not.

NSObject

Caveats while using Equatable with NSObject

Today I am going to talk about how to use Equatable with Swift and NSObject inherited objects. This is interesting because last week I came to know about the fact that Swift's inbuilt Equatable protocol does not play nice with objects inherited from NSObject Equality with Swift objects Let's look

Swift

Refactoring Gotcha

Today I am going to write about recent refactoring gotcha I ran into. Hopefully this won't be a long post as I usually do. So let's move directly to the coding example. I had a original code like this. (Which was needed to be refactored considering most recent requirement) // For

Monty-Hall problem

Implementing Monty-Hall problem

Today, I am going to write about the Monty-Hall problem simulation I ran programmatically. What is this Monty-Hall problem you may ask? According to Wikipedia [https://en.wikipedia.org/wiki/Monty_Hall_problem], > The Monty Hall problem is a brain teaser, in the form of a probability puzzle, loosely based

Swift

Swift - Fighting memory leaks in closures

Swift is a great language. In fact, it's among my top 3 favorite languages. It is quite strict in terms of discipline and best practices which pay off in the long-term to offer performance and crash-free experience to end-users. There are also many ways where things can go wrong. Today

Xcode 9

Random Xcode Trick

Despite my regular rantings on Xcode and Apple software, I still love them. In past few years, I have used so many IDEs and trust me, Xcode is one of the best I have seen. However, it has its bad times and tantrums - But it is understandable with its

Swift 4.0

Using Swift variables in Objective-C : Swift 4 Edition

Today I ran into weird problem which prompted me to write this blog post on Objective-C and Swift interconnectedness. Before Swift 4 came along, the sure way to access Swift variables in Objective-C was to inherit class from NSObject (Swift structs cannot be used in the Objective-C) and prefix it

Swift 3.0

Functional magic with Swift

Last few days I have been experimenting with functional magic in Swift. Especially how map and flatMaps work. I was so amazed to know how hassle-free my life became after I understood and harnessed the power of functional magic in Swift. I strongly encourage you to do so as well.

Swift

Closure Trick in Swift

Today I learned a closure trick in Swift. Usually when expression is assigned to a variable on left, it is evaluated instantly. For example, let value = complexCalculation() func complexCalculation() -> String { return "Something useful" } In this example, when value is assigned a result of complexCalculation() method, it is called immediately.

MVVM

Comparing VIPER vs. MVVM

Recently I started playing with VIPER architecture. Although I was quite hesitant trying it out, it turns out it's not all that bad as I expected. It'e certainly better than traditional MVC iOS architecture in terms of testability and separation of concerns. However, I found it consistently annoying to have

Touch

Touch ID Authentication in the app

Today I am going to write about implementing and using Touch ID authentication in an iOS app. Touch ID authentication API was introduced in iOS 8 release. It is a part of LocalAuthentication framework. The code to include it in your app spans only few lines and easy to integrate.