Add LazyVGrid case study

Author: ole

ViewLifecycle.xcodeproj/project.pbxproj

@@ -8,6 +8,7 @@
 
 /* Begin PBXBuildFile section */
 		5D0520B72934DC330080E4C0 /* CaseStudyStaticList.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5D0520B62934DC330080E4C0 /* CaseStudyStaticList.swift */; };
+		5D0520B92934E6130080E4C0 /* CaseStudyLazyVGrid.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5D0520B82934E6130080E4C0 /* CaseStudyLazyVGrid.swift */; };
 		5D305D20293240F300E42700 /* OnAppearMonitor.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5D305D1F293240F300E42700 /* OnAppearMonitor.swift */; };
 		5D305D222932444500E42700 /* CaseStudyScrollView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5D305D212932444500E42700 /* CaseStudyScrollView.swift */; };
 		5D305D242932547F00E42700 /* CaseStudyList.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5D305D232932547F00E42700 /* CaseStudyList.swift */; };
@@ -22,6 +23,7 @@
 
 /* Begin PBXFileReference section */
 		5D0520B62934DC330080E4C0 /* CaseStudyStaticList.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CaseStudyStaticList.swift; sourceTree = "<group>"; };
+		5D0520B82934E6130080E4C0 /* CaseStudyLazyVGrid.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CaseStudyLazyVGrid.swift; sourceTree = "<group>"; };
 		5D305D1F293240F300E42700 /* OnAppearMonitor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = OnAppearMonitor.swift; sourceTree = "<group>"; };
 		5D305D212932444500E42700 /* CaseStudyScrollView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CaseStudyScrollView.swift; sourceTree = "<group>"; };
 		5D305D232932547F00E42700 /* CaseStudyList.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CaseStudyList.swift; sourceTree = "<group>"; };
@@ -67,6 +69,7 @@
 			isa = PBXGroup;
 			children = (
 				5D6C3F6B2908541100A0C864 /* App.swift */,
+				5D0520B82934E6130080E4C0 /* CaseStudyLazyVGrid.swift */,
 				5D305D232932547F00E42700 /* CaseStudyList.swift */,
 				5D305D25293260BE00E42700 /* CaseStudyScrollViewVStackForEach.swift */,
 				5D305D212932444500E42700 /* CaseStudyScrollView.swift */,
@@ -160,6 +163,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				5D0520B92934E6130080E4C0 /* CaseStudyLazyVGrid.swift in Sources */,
 				5D0520B72934DC330080E4C0 /* CaseStudyStaticList.swift in Sources */,
 				5D305D2A293266D000E42700 /* CaseStudyTabView.swift in Sources */,
 				5D305D28293260EC00E42700 /* Model.swift in Sources */,

ViewLifecycle/CaseStudyLazyVGrid.swift

@@ -0,0 +1,38 @@
+import SwiftUI
+
+struct CaseStudyLazyVGrid: View {
+    @State private var items: [Item] = sampleItems
+
+    var body: some View {
+        ScrollView {
+            LazyVGrid(columns: [.init(.adaptive(minimum: 280))]) {
+                ForEach(items) { item in
+                    let label = String(item.id.uuidString.prefix(8))
+                    OnAppearMonitor(label: label)
+                }
+            }
+        }
+        .navigationTitle("LazyVGrid")
+        .toolbar {
+            ToolbarItem {
+                Button("Prepend") {
+                    let newItem = Item(id: UUID())
+                    items.insert(newItem, at: 0)
+                }
+            }
+            ToolbarItem {
+                Button("Append") {
+                    let newItem = Item(id: UUID())
+                    items.append(newItem)
+                }
+            }
+        }
+        .animation(.default, value: items)
+    }
+}
+
+struct CaseStudyLazyVGrid_Previews: PreviewProvider {
+    static var previews: some View {
+        CaseStudyLazyVGrid()
+    }
+}

ViewLifecycle/RootView.swift

@@ -31,6 +31,10 @@ extension CaseStudy {
         label: "List with dynamic content",
         description: "List recycles views during scrolling, so onAppear gets called often. But List preserves the State for all list items."
     )
+    static let lazyVGrid: Self = .init(
+        id: "lazyVGrid",
+        label: "LazyVGrid"
+    )
     static let tabView: Self = .init(
         id: "tabView",
         label: "TabView",
@@ -56,7 +60,14 @@ let categories: [Category] = [
         ]
     ),
     Category(
-        id: "tabview",
+        id: "lazy",
+        label: "Lazy Containers",
+        elements: [
+            .lazyVGrid,
+        ]
+    ),
+    Category(
+        id: "tabView",
         label: "TabView",
         elements: [
             .tabView,
@@ -123,6 +134,8 @@ struct Primary: View {
             CaseStudyStaticList()
         case .list:
             CaseStudyList()
+        case .lazyVGrid:
+            CaseStudyLazyVGrid()
         case .tabView:
             CaseStudyTabView()
         default: