Quickies for SwiftUI

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Random

• Adding a new environment value [permalink]
  

  private struct ScreamAtMeKey: EnvironmentKey {
      static let defaultValue = false
  }
  
  // Set via .environent(\.screamAtMe, true)
  extension EnvironmentValues {
      var screamAtMe: Bool {
          get { self[ScreamAtMeKey.self] }
          set { self[ScreamAtMeKey.self] = newValue }
      }
  }
  
  // Set via .screamAtMe(true)
  extension View {
      func screamAtMe(_  aaaaaah: Bool) -> some View {
          environment(.screamAtMe, aaaaaah)
      }
  }
  

• Basic Tab View [permalink]
  

  struct ContentView: View {
      var body: some View {
          TabView {
              SimplePlan()
                .badge(23)
                .tabItem {
                    Label("Simple Plan", systemImage: "house")
                }
              MultiPlan()
                .tabItem {
                    Label("Simple Plan", systemImage: "house.lodge")
                }
          }
      }
  }
  

• Default to a particular tab bar tab [permalink]
  

  enum Tab: Hashable {
      case simplePlan
      case complicatedPlan
      case multiPlan
  
      var id: Self { self }
  }
  
  struct ContentView: View {
      @State private var tab = Tab.complicatedPlan
  
      var body: some View {
          TabView(selection: $tab) {
              SimplePlan(captureModel: SimpleCaptureModel.shared)
                .tabItem {
                    Label("Simple Plan", systemImage: "house")
                }
                .tag(Tab.simplePlan)
              CompliPlan(captureModel: CompliCaptureModel.shared)
                .tabItem {
                    Label("Complicated Plan", systemImage: "house.circle.fill")
                }
                .tag(Tab.complicatedPlan)
              MultiPlan()
                .tabItem {
                    Label("Multi Plan", systemImage: "house.lodge")
                }
                .tag(Tab.multiPlan)
          }
      }
  }
  

• Easily giving buttons a border/background [permalink]
  I still dislike the iOS 7 "here's some random blue text. Really, it's a button". I like buttons to look like buttons. You can add a `.buttonStyle` to a view, and it'll apply the style to al the buttons inside. Here's the different out of the box styles. You can also make your own custom button style.

          .buttonStyle(.bordered)  // gray filled oval
          .buttonStyle(.borderedProminent) // blue filled oval
          .buttonStyle(.borderless) // default (I think) - free floating random blue text
          .buttonStyle(.plain)  // free floating random plain text. that's also a button
  

• Making a custom button style [permalink]
  

  struct CustomButtonStyle: ButtonStyle {
      func makeBody(configuration: Configuration) -> some View {
          configuration.label
              .padding()
              .background(.purple)
              .foregroundStyle(.green)
              .clipShape(RoundedRectangle(cornerRadius: 25, style: .continuous))
              .scaleEffect(configuration.isPressed ? 2.0 : 1)
              .animation(.easeOut(duration: 0.05), value: configuration.isPressed)
      }
  }
  

  (please don't actually make buttons with this style...) And then attach it to something (say an individual button, or a top-level view) like

          .buttonStyle(CustomButtonStyle())
  

• Making a simple button [permalink]
  

  Button("Button Text") {
      print("Snorgle")
  }
  

• Wrapping a UIView [permalink]
  Given a UIView, add it to SwiftUI via UIViewRepresentable.

  struct PlaceholderContainerView: UIViewRepresentable {
  
      func makeUIView(context: Context) -> PlaceholderUIView {
          return PlaceholderUIView()
      }
  
      func updateUIView(_ uIView: PlaceholderUIView, context: Context) {
          print("update ui view (context)")
      }
  }
  

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