From 939e80d66d0e4ea40a8949c79057428a8d3bea04 Mon Sep 17 00:00:00 2001
From: Laurent <laurent@staxriver.com>
Date: Thu, 2 Mar 2023 10:58:17 +0100
Subject: [PATCH] manage split view column visibility

---
 .../Model/NSManagedContext+Extensions.swift   |  5 +++++
 LeCountdown/Views/HomeView.swift              | 22 +++++++++++++++++--
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/LeCountdown/Model/NSManagedContext+Extensions.swift b/LeCountdown/Model/NSManagedContext+Extensions.swift
index 3531876..285fa24 100644
--- a/LeCountdown/Model/NSManagedContext+Extensions.swift
+++ b/LeCountdown/Model/NSManagedContext+Extensions.swift
@@ -37,6 +37,11 @@ extension NSManagedObjectContext {
         return try self.fetch(request)
     }
     
+    func count(entityName: String) throws -> Int {
+        let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: entityName)
+        return try self.count(for: fetchRequest)
+    }
+    
 }
 
 extension NSManagedObject {
diff --git a/LeCountdown/Views/HomeView.swift b/LeCountdown/Views/HomeView.swift
index caaaee3..bbe927e 100644
--- a/LeCountdown/Views/HomeView.swift
+++ b/LeCountdown/Views/HomeView.swift
@@ -58,14 +58,16 @@ struct RegularHomeView: View {
 
     @State private var tabSelection: Int = 1
     
+    @State private var columnVisibility: NavigationSplitViewVisibility = .detailOnly
+    
     var body: some View {
         
-        NavigationView {
+        NavigationSplitView(columnVisibility: $columnVisibility) {
             PresetsView(tabSelection: $tabSelection)
                 .environment(\.managedObjectContext, viewContext)
                 .tabItem { Label("Presets", systemImage: "globe") }
                 .tag(0)
-
+        } detail: {
             TabView(selection: $tabSelection) {
                 ContentView<AbstractTimer>()
                     .environment(\.managedObjectContext, viewContext)
@@ -78,12 +80,28 @@ struct RegularHomeView: View {
                     .tag(2)
             }.tabViewStyle(.page(indexDisplayMode: .never))
         }
+        .onAppear {
+            self._setColumnVisibility()
+        }
         .onContinueUserActivity(Shortcut.newCountdown.rawValue, perform: _handleNewCountdown)
         .onOpenURL { _ in
             self.tabSelection = 1
         }
     }
     
+    fileprivate func _setColumnVisibility() {
+        do {
+            let count = try viewContext.count(entityName: "AbstractTimer")
+            if count > 0 {
+                self.columnVisibility = .detailOnly
+            } else {
+                self.columnVisibility = .automatic
+            }
+        } catch {
+            Logger.error(error)
+        }
+    }
+    
     fileprivate func _handleNewCountdown(_ userActivity: NSUserActivity) {
         print(">>> new countdown")
     }