Скачать или смотреть Why is My SF Symbol Blurry in a UIImage? Here's the Solution!

Discover why displaying SF Symbols in a UIImage leads to a blurry rendering in SwiftUI, along with an effective solution to handle images cleanly.
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Understanding the Blurriness of SF Symbols in UIImage

If you've been using SwiftUI and have encountered the issue of blurry images when inserting SF Symbols into a UIImage, you're not alone. Many developers stumble upon this frustrating problem when trying to implement a clean and dynamic image display. Whether you're working on a simple app or a more complex interface, dealing with image quality can make a significant impact on the user experience.

In this guide, we'll break down the issue and provide you with a clear solution to display SF Symbols without compromising image quality.

The Problem: Blurry Images in SwiftUI

When adding an SF Symbol to a UIImage and then rendering it in a SwiftUI Image view, such as in the following code:

[[See Video to Reveal this Text or Code Snippet]]

You'll notice that while the second Image(systemName:) renders crisply, the first Image(uiImage:) tends to be blurry.

What Causes the Blurriness?

The blurriness stems from the distinction between vector graphics and bitmapped images:

Vector Graphics: When you use Image(systemName:), SwiftUI uses vector graphics. This means that the image is drawn to the screen using vector-based representations, which scale beautifully at any resolution without losing clarity.

Bitmap Images: On the other hand, when you create a UIImage, like using UIImage(systemName:), you're working with a bitmap image that has a fixed resolution. If you try to scale it larger than its original dimensions, you will encounter blurriness because you're stretching a raster image beyond its designed limits.

The Solution: Conditional Image Display

To create a solution that allows for clear image rendering regardless of whether you're displaying a UIImage or an SF Symbol, consider the following approach, which utilizes Swift's conditionals:

[[See Video to Reveal this Text or Code Snippet]]

How This Works

State Management: The @ State variable displayedImage holds either a UIImage or <nil>.

Conditional Logic: The computed property imageToDisplay checks if displayedImage has a valid image and selects the appropriate Image type:

If a valid UIImage exists, it's rendered without loss of clarity.

If it’s nil, it defaults to rendering an SF Symbol instead.

Simple Modifiers: The same modifiers are applied to both image types, ensuring that they maintain consistent display properties.

Conclusion

By understanding the difference between vector graphics and bitmap images, and implementing a conditional display strategy, you can effectively eliminate the issue of blurry images in your SwiftUI applications. This approach not only preserves the visual integrity of SF Symbols but also enhances the overall quality of your application's user interface.

Happy coding, and may your apps always look crisp and clear!