Learn How to Create iOS Apps
The Slider has been around in iOS since the beginning. Apple included it in the SwiftUI framework beginning with iOS 13. The slider is a simple UI control that allows you to slide your finger across the screen and update a value behind the scenes. The last time I wrote about it was about 12 years ago demonstrating it with Objective-C code and a Storyboard. It’s time to provide a more current example.
When an app needs to take time to process something, such as waiting for a download or processing information, it’s ideal to provide a visual cue to show that something is happening. Depending on the task, you might choose to display a progress meter that estimates, or provides, the progress. Alternatively, you could simply show an animation to indicate that something is happening.
Today we’ll look at the latter and create a custom loading spinner.
[Read more…]The @Environment property wrapper in SwiftUI gives access to shared values across your app. Apple provides a wide range of values that are built-in to every app. These cover accessibility, layout, colours, and more. The system automatically updates the built-in environment values so that your app knows more about the environment it is running in.
Lets take a look at examples of the available @Environment values. The best way to explain is by diving into the code.
[Read more…]Building an app that works on both iPhone and iPad isn’t particularly complicated. SwiftUI provides the necessary tools to adapt to different screen sizes so that users get the best experience for the device they are currently using.
In this tutorial we’ll look at how to build a responsive design that works on the smaller iPhone screen as well as the larger screens found on the iPad. As a bonus, we’ll use the “Mac (Designed for iPad)” setting in the target so that you can use the app on any Mac that uses Apple Silicon.
[Read more…]The SwiftUI framework provides the tools you need to create the layout of your app. Two of these are the Spacer and Divider, both of which are views as they conform to the View protocol.
When creating iPhone apps you will come across times when you can use single instance of a class across an entire app. Network manager, audio player, and other classes that Apple provides are called Singletons. It is one of the design patterns used in iOS app development.
A singleton ensures that only one instance of the class exists across the entire app. One example is App Settings, and another is a connection to a database where you probably want just a single connection.
Although singletons are relatively easy to create, meaning the syntax to allow a class to be a singleton, you need to be careful how you create it to avoid tight coupling and hidden dependencies.
[Read more…]A long time ago, back in 2013 and just prior to Swift launching, I created a tutorial in Objective-C called AVSpeechSynthesizer Tutorial – Letting Your App Speak Like Siri. A lot of things have changed since then in that we now have Swift, SwiftUI, and personalised voice. People with iPhone 12 or later, and various Mac and iPad devices, can spend time recording phrases on the screen, and after the device has processed those phrases, you then have a personalised voice that can be used in various places on the phone.
This tutorial looks at how to use AVSpeechSynthesizer to select your voice and get yourself to speak anything you type in.
[Read more…]SwiftUI views work with view modifiers that make it really simple to create great effects. In this tutorial, we’ll look at making a rounded profile picture that you might use on a profile page in your app.
This particular profile picture (not me), is created with an Image view with several view modifiers to clip the corners to make a circle as well as add a small border around it. The result looks surprisingly good.
String interpolation is an extremely convenient way to mix variables, constants, and expressions into a string. It is extremely common to use this within your app. In this tutorial we’ll look at how you can use it in your own app.
[Read more…]A class in Swift, like classes in other programming languages, serves as a blueprint for creating objects that encapsulate data and behaviour. In Swift, you will see both classes and structs. This post will primarily focus on classes, although I will mention structs throughout to highlight some of the differences.
Classes are reference types, meaning that if you instantiate it, and then make a copy of it, any changes to either copy will be reflected in the other copy.
class Car {
var model: String
init(model: String) {
self.model = model
}
}
let car1 = Car(model: "Ferrari")
let car2 = car1
car2.model = "Lamborghini"
print(car1.model)
Although we changed car2’s model, because car2 is a copy of car1, and that it copies by reference, any changes to car2 here will also be changing car1.
[Read more…]