Learn how to create a dynamic SwiftUI app with JSON API integration

Learn how to create a dynamic SwiftUI app with JSON API integration

Table of Contents

1. Introduction
2. Setting Up the Architecture
3. Fetching and Displaying Categories
4. Creating the Category Listing Screen
5. Displaying Categories and Async Images
6. Conclusion

Introduction

Welcome to Adam Sharp Weekly! In this video, we will learn how to Create a Servio application that consumes and creates data from a JSON API. This tutorial series will cover multiple videos and will utilize the Classy Fake Store API, which has excellent documentation. Before we begin the implementation, let's take a look at what we will be building—a store app with various categories and items, all sourced from the JSON API.

Setting Up the Architecture

To start our implementation, we need to create a system for switching between development and production environments. This can be achieved by creating an extension or configuration that handles different URLs for each environment. We will create an extension called "URL+Extensions" and define properties for the development and production URLs. We will also include a default property that returns the appropriate URL Based on the Current environment. Additionally, we will create a property called "categories" in the extension to represent the URL for fetching categories.

Next, we will create an HTTP client, also known as a web service or web client, which will handle the communication with the API. We will start by creating a function called "getCategories" in the "StoreHTTPClient" class. This function will take a URL as input and return the categories obtained from the API. We will use URLSession.shared and the dataTask function to perform the HTTP request. We will also handle the response code and throw an error if the response is invalid. Finally, we will decode the JSON data into a Category model and return the categories.

Fetching and Displaying Categories

Now that we have set up the architecture, we can fetch and display the categories in our app. We will create a store model, which will serve as the main data source for our application. This model will provide the categories and products to other views. To fetch the categories, we will create a function called "fetchCategories" in the store model. This function will use the store HTTP client to fetch the categories from the API. We will assign the fetched categories to a property called "allCategories" in the store model.

Next, we will create a screen called "CategoryListScreen" to display the categories. We will inject the store model as an environment object so that it can be accessed by the screen and its child views. In the screen, we will use the List view to iterate over the categories and display their names. We will also display an error message if there is an error fetching the categories.

Creating the Category Listing Screen

The Category Listing Screen will serve as the root view of our application. We will create an environment object of the store model and inject it into the screen. Inside the screen, we will use the List view to display the categories fetched from the API. Additionally, we will display an async image for each category.

To display the async image, we will use the AsyncImage view and pass the category image URL as its parameter. We will also resize the image, set its frame, and add a rounded rectangle Shape to it. This will provide a visually appealing display for the categories.

Displaying Categories and Async Images

With just a few lines of code, We Are able to display the categories and their associated async images on our screen. The architecture we have implemented allows us to easily fetch the data from the API using the store model and display it in the Category Listing Screen. We have also added error handling to display any errors encountered during the fetch process.

Conclusion

In this video, we have learned how to set up the architecture for our Servio application and fetch categories from the JSON API. We have created a store model, a store HTTP client, and a category listing screen to display the categories. Additionally, we have implemented error handling to display any errors encountered during the fetch process.

Stay tuned for the next video, where we will learn how to display the products associated with a selected category. Make sure to check out the GitHub link in the description to download the code and explore more about this project. Thank You for watching, and I hope you enjoy the rest of the series!

Highlights

• Create a Servio application that consumes and creates data from a JSON API
• Utilize the Classy Fake Store API with excellent documentation
• Set up the architecture for switching between development and production environments
• Fetch and display categories from the JSON API using a store model and HTTP client
• Create a category listing screen to display the categories and their associated async images
• Implement error handling to display any errors encountered during the fetch process

FAQ

Q: How can I switch between development and production environments?

A: By creating an extension or configuration that handles different URLs for each environment, you can switch between development and production environments easily.

Q: Can I reuse the category listing screen in different parts of my application?

A: Yes, you can reuse the category listing screen in different parts of your application by injecting the store model as an environment object. This allows you to access the categories data in any view that requires it.

Q: How can I handle errors during the fetch process?

A: You can handle errors during the fetch process by implementing error handling mechanisms, such as try-catch blocks. In the provided code, an error message is displayed if there is an error fetching the categories from the API.

Q: Can I customize the appearance of the async images?

A: Yes, you can customize the appearance of the async images by modifying the parameters passed to the AsyncImage view. For example, you can change the resizing, frame, and shape of the image to fit your desired design.