Reduce iOS workspace row swipe contention

Author: azooz2003-bit

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/DeviceTreeView.swift

@@ -37,6 +37,7 @@ struct DeviceTreeView: View {
     /// The active workspace-row filter (All / Unread), the same shared model the
     /// flat list uses, applied to every expanded instance's workspace leaves.
     @State private var filter: MobileWorkspaceListFilter = .all
+    @State private var timestampReferenceDate = Date.now
 
     private var expansion: DeviceTreeExpansionStore {
         DeviceTreeExpansionStore(storage: expandedStorage)
@@ -85,6 +86,11 @@ struct DeviceTreeView: View {
                 await store.loadPairedMacs()
                 await store.loadRegistryDevices()
             }
+            .task {
+                await WorkspaceRelativeTimestampClock().run {
+                    timestampReferenceDate = $0
+                }
+            }
         }
         .accessibilityIdentifier("MobileDeviceTree")
     }
@@ -206,6 +212,7 @@ struct DeviceTreeView: View {
                         navigationStyle: .push,
                         wrapWorkspaceTitles: displaySettings.wrapWorkspaceTitles,
                         previewLineLimit: displaySettings.workspacePreviewLineCount,
+                        timestampReferenceDate: timestampReferenceDate,
                         selectWorkspace: { id in
                             selectWorkspace(id)
                             dismiss()

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/MobileWorkspacePreview+Display.swift

@@ -43,8 +43,8 @@ extension MobileWorkspacePreview {
 
     /// The row's trailing slot: the connection problem when there is one,
     /// otherwise the compact relative activity time. `now` is threaded from the
-    /// row's `TimelineView` so the label refreshes as time passes and stays
-    /// deterministic in tests.
+    /// row so the label stays deterministic in tests without each row owning a
+    /// live timer.
     func timestampOrStatus(connectionStatus: MobileMacConnectionStatus, now: Date) -> String {
         if connectionStatus != .connected {
             return connectionStatus.label

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceListView.swift

@@ -70,6 +70,7 @@ struct WorkspaceListView: View {
     /// Stored at list scope so reusable rows do not own transient presentation
     /// state while `List` is recycling swipe-action rows.
     @State private var workspacePendingCloseID: MobileWorkspacePreview.ID?
+    @State private var timestampReferenceDate = Date.now
 
     private var trimmedQuery: String {
         searchText.trimmingCharacters(in: .whitespacesAndNewlines)
@@ -148,6 +149,11 @@ struct WorkspaceListView: View {
         }
         .listStyle(.plain)
         .workspaceListRefreshable(refresh)
+        .task {
+            await WorkspaceRelativeTimestampClock().run {
+                timestampReferenceDate = $0
+            }
+        }
         .navigationTitle(L10n.string("mobile.workspaces.title", defaultValue: "Workspaces"))
         .mobileInlineNavigationTitle()
         .searchable(text: $searchText)
@@ -251,6 +257,7 @@ struct WorkspaceListView: View {
             navigationStyle: navigationStyle,
             wrapWorkspaceTitles: wrapWorkspaceTitles,
             previewLineLimit: previewLineLimit,
+            timestampReferenceDate: timestampReferenceDate,
             selectWorkspace: selectWorkspace,
             renameWorkspace: renameWorkspace,
             setPinned: setPinned,

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceNavigationRow.swift

@@ -11,6 +11,8 @@ struct WorkspaceNavigationRow: View {
     /// How many lines the activity preview shows (1 or 2), forwarded to the
     /// shared ``WorkspaceRow``.
     var previewLineLimit: Int = MobileDisplaySettings.defaultWorkspacePreviewLineCount
+    /// Shared parent-owned reference date for relative activity labels.
+    var timestampReferenceDate: Date = .now
     let selectWorkspace: (MobileWorkspacePreview.ID) -> Void
     /// Rename the workspace on the Mac. When `nil` (e.g. previews) the rename
     /// affordance is hidden.
@@ -35,16 +37,19 @@ struct WorkspaceNavigationRow: View {
     @State private var isRenaming = false
 
     var body: some View {
-        WorkspaceRow(
-            workspace: workspace,
-            connectionStatus: connectionStatus,
-            isSelected: navigationStyle == .sidebar && isSelected,
-            wrapWorkspaceTitles: wrapWorkspaceTitles,
-            previewLineLimit: previewLineLimit
-        )
-        .onTapGesture {
+        Button {
             selectWorkspace(workspace.id)
+        } label: {
+            WorkspaceRow(
+                workspace: workspace,
+                connectionStatus: connectionStatus,
+                isSelected: navigationStyle == .sidebar && isSelected,
+                wrapWorkspaceTitles: wrapWorkspaceTitles,
+                previewLineLimit: previewLineLimit,
+                timestampReferenceDate: timestampReferenceDate
+            )
         }
+        .buttonStyle(.plain)
         .contentShape(Rectangle())
         .contextMenu { contextMenu }
         .swipeActions(edge: .leading, allowsFullSwipe: true) {

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceRelativeTimestampClock.swift

@@ -0,0 +1,23 @@
+import Foundation
+import SwiftUI
+
+struct WorkspaceRelativeTimestampClock {
+    var interval: Duration = .seconds(60)
+
+    @MainActor
+    func run(update: @escaping @MainActor (Date) -> Void) async {
+        while !Task.isCancelled {
+            do {
+                try await Task.sleep(for: interval)
+            } catch {
+                return
+            }
+
+            var transaction = Transaction()
+            transaction.disablesAnimations = true
+            withTransaction(transaction) {
+                update(.now)
+            }
+        }
+    }
+}

Packages/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceRow.swift

@@ -1,5 +1,6 @@
 import CmuxMobileShellModel
 import CmuxMobileSupport
+import Foundation
 import SwiftUI
 
 struct WorkspaceRow: View {
@@ -13,6 +14,10 @@ struct WorkspaceRow: View {
     /// "Preview Lines" setting; 2 is the default). Space is reserved so rows
     /// with short previews keep the same height as their neighbors.
     var previewLineLimit: Int = MobileDisplaySettings.defaultWorkspacePreviewLineCount
+    /// Passive timestamp reference for the relative activity label. This avoids a
+    /// per-row `TimelineView` invalidating list rows while UIKit is tracking a
+    /// native swipe gesture.
+    var timestampReferenceDate: Date = .now
 
     var body: some View {
         HStack(alignment: .top, spacing: 12) {
@@ -40,16 +45,10 @@ struct WorkspaceRow: View {
 
                     Spacer(minLength: 8)
 
-                    // TimelineView re-evaluates the label every minute so a
-                    // quiet row's relative time ("now" -> "1m" -> ...) advances
-                    // without waiting for an unrelated state change to
-                    // invalidate the row. Minute granularity matches the label.
-                    TimelineView(.everyMinute) { context in
-                        Text(workspace.timestampOrStatus(connectionStatus: connectionStatus, now: context.date))
-                            .font(.subheadline)
-                            .foregroundStyle(.secondary)
-                            .lineLimit(1)
-                    }
+                    Text(workspace.timestampOrStatus(connectionStatus: connectionStatus, now: timestampReferenceDate))
+                        .font(.subheadline)
+                        .foregroundStyle(.secondary)
+                        .lineLimit(1)
                 }
 
                 Text(workspace.previewLine)