Скачать или смотреть Resolving Image Loading Issues in SwiftUI with Firebase Storage

Discover how to efficiently handle image loading in `SwiftUI` using `Firebase Storage`, ensuring that your views update correctly when images are changed asynchronously.
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This video is based on the question https://stackoverflow.com/q/66694643/ asked by the user 'Sebastian Fox' ( https://stackoverflow.com/u/11532731/ ) and on the answer https://stackoverflow.com/a/66696096/ provided by the user 'jnpdx' ( https://stackoverflow.com/u/560942/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

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Resolving Image Loading Issues in SwiftUI with Firebase Storage

As a developer working with SwiftUI and Firebase, you may encounter a common issue: the view not updating after an image is changed asynchronously. This problem can be particularly frustrating when you're trying to load images for user profiles from Firebase Storage. In this guide, we will explore the core issue and provide a detailed solution to ensure your SwiftUI views properly reflect loaded images.

Understanding the Problem

When building an app that relies on Firebase for user data, you may have a user model that includes a property for an image link. The workflow usually involves:

Loading user data from Firestore

Asynchronously fetching images from Firebase Storage based on these links

Displaying a placeholder until the images are fully loaded

The challenge arises when the images are successfully downloaded (as can be verified through debugging), but the SwiftUI views do not update to reflect the changed images. Instead, the placeholder remains visible.

The Solution: Using @ Published Properties

The root cause of the issue is often related to how data changes are communicated to the SwiftUI view. In older versions of SwiftUI, developers would use the BindableObject protocol and didChange to notify views of changes. This approach is now outdated and has been succeeded by the simpler @ Published property wrapper.

Step-by-Step Implementation

Here's how to refactor your code using @ Published to ensure that your views update correctly when images are fetched:

1. Modify the Loader Class

Begin by updating the Loader class to utilize @ Published properties. This will automatically notify any observing views when the data changes.

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2. Keeping the FirebaseImage View Structured

The FirebaseImage view can remain largely unchanged, as it is already designed to observe the Loader for changes. Here’s how it looks:

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3. Utilizing UsersViewModel to Fetch User Data

Ensure your UsersViewModel correctly fetches user data. It will automatically trigger view updates via the @ Published properties, maintaining the responsive nature of your app.

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Conclusion

By adopting the @ Published property wrapper within your data-loading classes, you can effectively resolve the issue of views not updating in SwiftUI. This approach not only simplifies your code but also aligns with the current best practices in SwiftUI development. Now, as your images are fetched, your views will automatically reflect those changes and provide a better user experience.

Make sure to implement these adjustments in your code, and you'll find that your SwiftUI app responds more accurately to asynchronous image loading through Firebase Storage.