shauns/ViewCollectionBuilders

SwiftUI - A set of useful building blocks to supplement `@ViewBuilder`

ViewCollectionBuilders

A set of useful building blocks to supplement @ViewBuilder.

CollectionViewBuilder<ViewType>

This helps you write functions or Views that work with a collection of child views. You can then build your own functionality to e.g. selectively show or use the child views. The child views all need to share some underlying type.

struct UsesCollection : View {
  var content: [Text]
  @Binding var index: Int
  
  init(index: Binding<Int>, @CollectionViewBuilder<Text> _ content: () -> [Text]) {
    self._index = index
    self.content = content()
  }

  var body: some View {
    content[index]
  }
}

// renders "World"
UsesCollection(index: Binding.constant(1)) {
  Text("Hello")
  Text("World")
}

TaggedViewDictionaryBuilder<KeyType: Hashable>

This helps you to write functions or views that use a mapping between some kind of tag, and underlying view functions. The TaggedView container must be used to wrap up the child views. The .tag() view modifier from SwiftUI is called on the child views as needed.

struct UsesMapping: View {
  var content: [String: () -> AnyView]
  @Binding var key: String
  
  init(key: Binding<String>, @TaggedViewDictionaryBuilder<String> _ content: () -> [String: () -> AnyView]) {
    self._key = key
    self.content = content()
  }
  
  var body: some View {
    content[key]()
  }
}

// renders AnotherView()
UsesMapping(key: Binding.constant("World")) {
  TaggedView("Hello") {
    SomeView()
  }
  TaggedView("World") {
    AnotherView()
  }
}

Helpers

The TaggedView and WithTag containers help with pairing a tag to a view function, the main difference being that WithTag has strongly typed content, but TaggedView is agnostic and wraps things up in an AnyView.