SwiftUI Conditionally disable modifier

user_16653398 0
Viewed 185

So say I want to conditionally enable or disable a modifier on a view such as matched geometry effect? As silly as this looks, how would I do this?

Image("Test")
   .scaleEffect(self.selectedImageScale)
   .offset(self.selectedImageOffset)
   .aspectRatio(contentMode: .fit)
if disabled {
   .matchedGeometryEffect(id: selectedImage.id, in: self.namespace)
}
swiftui
2 Answers

You can achieve it with a simple extension on the View:

extension View {

    @ViewBuilder
    public func `if`<T: View, U: View>(
        _ condition: Bool,
        then modifierT: (Self) -> T,
        else modifierU: (Self) -> U
    ) -> some View {

        if condition { modifierT(self) }
        else { modifierU(self) }
    }
}

Now you can use it like:

Image("Test")
   .scaleEffect(self.selectedImageScale)
   .offset(self.selectedImageOffset)
   .aspectRatio(contentMode: .fit)

   .if(disabled) { view in
       view.matchedGeometryEffect(id: selectedImage.id, in: self.namespace)
   } else { $0 } // returns unmodified view
user_56230350

You can't put an if around a modifier, but you can use a ternary statement inside the parameters of the modifier:

.matchedGeometryEffect(id: disabled ? 0 : selectedImage.id, in: self.namespace)

Not sure if 0 works here for a "disabled" id, depends on your ids.

user_178967760
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