1# Using modern SwiftUI API
2 
3- Always use `foregroundStyle()` instead of `foregroundColor()`.
4- Always use `clipShape(.rect(cornerRadius:))` instead of `cornerRadius()`.
5- Always use the `Tab` API instead of `tabItem()`.
6- Never use the `onChange()` modifier in its 1-parameter variant; either use the variant that accepts two parameters or accepts none.
7- Do not use `GeometryReader` if a newer alternative works: `containerRelativeFrame()`, `visualEffect()`, or the `Layout` protocol. Flag `GeometryReader` usage and suggest the modern alternative.
8- When designing haptic effects, prefer using `sensoryFeedback()` over older UIKit APIs such as `UIImpactFeedbackGenerator`.
9- Use the `@Entry` macro to define custom `EnvironmentValues`, `FocusValues`, `Transaction`, and `ContainerValues` keys. This replaces the legacy pattern of manually creating a type conforming to (for example) `EnvironmentKey` with a `defaultValue`, then extending `EnvironmentValues` with a computed property.
10- Strongly prefer `overlay(alignment:content:)` over the deprecated `overlay(_:alignment:)`. For example, use `.overlay { Text("Hello, world!") }` rather than `.overlay(Text("Hello, world!"))`.
11- Never use `.navigationBarLeading` and `.navigationBarTrailing` for toolbar item placement; they are deprecated. The correct, modern placements are `.topBarLeading` and `.topBarTrailing`.
12- Prefer to rely on automatic grammar agreement when dealing with English, French, German, Portuguese, Spanish, and Italian. For example, use `Text("^[\(people) person](inflect: true)")` to show a number of people.
13- You can fill and stroke a shape with two chained modifiers; you do *not* need an overlay for the stroke. The overlay was required previously, but this is fixed in iOS 17 and later.
14- When referencing images from an asset catalog, prefer the generated symbol asset API when the project is configured to use them: `Image(.avatar)` rather than `Image("avatar")`.
15- When targeting iOS 26 and later, SwiftUI has a native `WebView` view type that replaces almost all uses of hand-wrapped `WKWebView` inside `UIViewRepresentable`. To use it, make sure to include `import WebKit`.
16- `ForEach` over an `enumerated()` sequence should not convert to an array first. Use `ForEach(items.enumerated(), id: \.element.id)` directly.
17- When hiding scroll indicators, use `.scrollIndicators(.hidden)` rather than `showsIndicators: false` in the initializer.
18- Never use `Text` concatenation with `+`.
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20For example, the usage of `+` here is bad and deprecated:
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22```swift
23Text("Hello").foregroundStyle(.red)
24+
25Text("World").foregroundStyle(.blue)
26```
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28Instead, use text interpolation like this:
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30```swift
31let red = Text("Hello").foregroundStyle(.red)
32let blue = Text("World").foregroundStyle(.blue)
33Text("\(red)\(blue)")
34```
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37## Using ObservableObject
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39If using `ObservableObject` is absolutely required – for example if you are trying to create a debouncer using a Combine publisher – you should always make sure `import Combine` is added. This was previously provided through SwiftUI, but that is no longer the case.
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