Скачать или смотреть How to Automatically Update Your NFC View in SwiftUI after Scanning

Learn how to seamlessly update your SwiftUI view when an NFC scan is completed, providing a better user experience for your application.
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How to Automatically Update Your NFC View in SwiftUI after Scanning

If you're developing an iOS application with NFC capabilities using Swift, you might encounter the challenge of displaying the scanned NFC data. Specifically, you may want your app to automatically refresh the displayed information as soon as an NFC tag is detected. This enhances the user experience by providing immediate feedback without requiring user interaction. In this guide, we'll explore how to implement this feature effectively using Swift's ObservableObject protocol in conjunction with SwiftUI.

Understanding the Problem

When your application reads from an NFC card using the CoreNFC framework, the typical flow involves starting a scan and waiting for the feedback. Once a tag is detected, data is usually processed or displayed, often requiring an additional user action (like pressing a button) to see the latest results. However, we aim to streamline this process so that the user can see the information immediately upon detection.

Solution Overview

To achieve automatic updates to the view when NFC scanning is completed, we can utilize SwiftUI's reactive framework. By employing the ObservableObject protocol, we can automatically trigger UI updates when the underlying data changes. Here's a structured approach to implement this:

Step 1: Update the NFCReader Class

We need to modify our NFCReader class to conform to ObservableObject. This change allows our application to observe changes to its properties. We will also use the @Published property wrapper for our detected variable, ensuring that any updates to this variable trigger a UI refresh.

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Step 2: Implementing the SwiftUI View

Next, we need to set up our view in SwiftUI to observe the NFCReader class. We'll use the @StateObject property to instantiate the NFCReader and display the newly detected messages as they come in.

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Key Points to Remember

ObservableObject Protocol: This enables communication between your model and view. Changes in your data model can automatically update your UI.

@Published Property Wrapper: Use this to declare properties you want to observe. When these properties change, SwiftUI will refresh the views that depend on them.

UI Updating: By leveraging the reactive nature of SwiftUI, we can create more intuitive and dynamic applications that respond seamlessly to user interactions and data changes.

Conclusion

By updating your NFC reading mechanism to use SwiftUI's ObservableObject, you've made it possible to display NFC data on your app instantly as tags are scanned. This not only enhances the user experience but also demonstrates the power of Swift and SwiftUI's declarative syntax for building modern applications. Now, your users can enjoy a fluid interaction with your NFC functionality without additional clicks or refresh actions. Happy coding!