iOS

A collection of 95 posts

Advanced SwiftUI

Two-way Bindings in SwiftUI

Bindings and Observables are essential for the basic SwiftUI mechanism. One-way bindings are easier, but what about two-way bindings? You want two values to set observers on each other and when one of them changes, it should also reflect that change in the other value. In Xcode 13.x and

low data mode

Low Data Mode on iOS 13

Apple introduced a low data mode feature in iOS 13. Using this mode, (On iOS 13), users can specify their preference to minimize the data usage when the network is really bad or they want to save on their data while being on the cellular. When the low data mode

Combine

Building a Network Service in Swift Using the Combine Framework

Hello readers! Welcome to another blog post. Today we are going to see how to build a generic network service using Apple's Combine framework. Making network calls from the app is the bread and butter of any standard iOS application. Today, we will see how to build a network service

XCTest

Handling Expected Unit Test Failures in Swift and Xcode

Xcode allows developers to make unit testing efficient and free from noise by skipping certain tests with known failure. There are many cases where engineers want unit tests to effectively catch failing code. But how about those where they know tests will fail, but still want to keep those tests

webSocket

WebSockets on iOS using URLSessionWebSocketTask

iOS added support for WebSocket starting iOS 13 and they announced it in WWDC2019 [https://wwdc.io/share/wwdc19/712]. Before that, developers had to rely on third-party libraries such as Starscream [https://github.com/daltoniam/Starscream] or SwiftWebSocket [https://github.com/tidwall/SwiftWebSocket]. Now with native support, it all

iOS

[iOS][Swift] Adding timer on reusable UITableViewCells

A few months ago I started the job search and in my very first take-home assignment, I was asked to implement a feature to display timer on UITableViewCell. The use-case was we were going to fetch Bitcoin prices every 60 seconds and the cell would display how long it is

UITableView

Best practices for configuring the table view cells on iOS with Swift

Many times, iOS developers utilize UITableView and UITableViewCell subclasses and sometimes UICollectionView variants to create beautiful views. But it could be tricky when you're writing it for the first time. It's important to know the best practices on how to configure these cells. In this post, I am going to

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

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

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

iOS

Making user friendly mobile apps

We all love using apps, don't we? They are great utility and ubiquitous after the propagation of smartphones all around us. However, as I do and I am sure lots of other people would be experiencing glitches that could lead to bad user experience. In this post, I will list

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.

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

Regular Expressions

How to use Regular Expressions (Regex) in Swift and iOS

Regular expressions are a powerful language feature. It allows you to find matches, extract text, or even replace strings in the given input of text. Like many developers, I've had a fair share of fighting with them eventually leading to a loss of confidence and productivity. Every time I need

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.

iOS

Swift 4 - Multiline string literals support

Multi-line support in Swift 4. Now add multi line support with double quotes using Swift 4 and Xcode 9. Tutorial with example on adding support.

UIKit

Using Autolayout to Dynamically Resize UILabel

We all love Autolayout, don't we? I had a less than ideal experience with it when I started. However, after continuous practice and reading a Book - iOS Auto Layout Demystified I got more comfortable with it. However, there are certain cases where it's still possible to solve problem with

iOS

Writing an app with VIPER architecture - Part 2

> I have written a part 1 of writing an iOS app [https://jayeshkawli.ghost.io/writing-an-ios-app-with-viper-architecture-part-1/] using VIPER architecture. This covers fundamentals and basic example of using VIPER, creating models, entities and utilizing them in the app. This is the second and final part in the series. This will be

iOS

Writing an app with VIPER architecture - Part 1

Last week I came across one of the many awesome frameworks on iOS. Having recently worked with MVVM and MVC, I was bit hesitant to learn VIPER, since more frameworks you learn, there is good chance you will forget the previous ones. However, I tried to keep my previous teaching

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

Facebook

An iOS library to apply Pride Effect

> A Library to apply Facebook style pride parade effect to photos With the ongoing LGBT pride month, it reminds me of the pride effect I created a couple of years back. My original source of inspiration was Facebook which allowed people to overlay their photos with pride theme colors [https:

iOS

List of Interview Questions for iOS Developers

Over the years of iOS development has taught me some interesting facts about Objective-C and Swift. Some of them I learned from my own experience and most of them either from senior colleagues or other online resources (Attributions added to the end). Based on this knowledge I have compiled a