[feat] support adaptive tablet layouts on Android and iPad

apps/ios/CrossDeskMobile/AnnouncementInboxView.swift

@@ -108,6 +108,8 @@ struct AnnouncementInboxView: View {
                 Text("共 \(inbox.state.total) 条 · \(inbox.state.unread) 条未读")
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("通知公告")
         .navigationBarTitleDisplayMode(.inline)
         .toolbar {
@@ -174,10 +176,12 @@ struct AnnouncementDetailView: View {
                         })
                 }
                 .padding(20)
+                .readableContentWidth()
             } else {
                 Text("这条公告已更新或删除，请返回公告列表查看。")
                     .foregroundStyle(.secondary)
                     .padding(20)
+                    .readableContentWidth()
             }
         }
         .navigationTitle("公告详情")

apps/ios/CrossDeskMobile/ContentView.swift

@@ -1,6 +1,19 @@
 import SwiftUI
 import UIKit
 
+enum MobileLayout {
+    static let twoColumnBreakpoint: CGFloat = 900
+    static let homeMaximumWidth: CGFloat = 1200
+    static let readableMaximumWidth: CGFloat = 720
+}
+
+extension View {
+    func readableContentWidth() -> some View {
+        frame(maxWidth: MobileLayout.readableMaximumWidth)
+            .frame(maxWidth: .infinity)
+    }
+}
+
 enum HomeDestination: Hashable {
     case settings
     case announcements
@@ -207,8 +220,11 @@ private struct ConnectionHomeView: View {
         return "arrow.triangle.2.circlepath"
     }
 
-    private var recentConnectionColumns: [GridItem] {
-        [
+    private func recentConnectionColumns(windowWidth: CGFloat) -> [GridItem] {
+        if windowWidth >= 600 {
+            return [GridItem(.adaptive(minimum: 180), spacing: 12, alignment: .top)]
+        }
+        return [
             GridItem(.flexible(), spacing: 12, alignment: .top),
             GridItem(.flexible(), spacing: 12, alignment: .top)
         ]
@@ -229,15 +245,33 @@ private struct ConnectionHomeView: View {
         ZStack {
             Color(.systemGroupedBackground).ignoresSafeArea()
 
-            VStack(spacing: 0) {
-                remoteConnectionPanel
+            GeometryReader { proxy in
+                let isWide = proxy.size.width >= MobileLayout.twoColumnBreakpoint
+                // AnyLayout keeps the fields, focus and scroll view alive when
+                // rotation or iPad multitasking crosses the layout breakpoint.
+                let layout = isWide
+                    ? AnyLayout(HStackLayout(alignment: .top, spacing: 24))
+                    : AnyLayout(VStackLayout(spacing: 20))
+
+                ScrollView(.vertical) {
+                    layout {
+                        remoteConnectionPanel
+                            .frame(width: isWide ? 360 : nil)
+                        recentConnectionsPanel(windowWidth: proxy.size.width)
+                            .frame(maxHeight: .infinity)
+                    }
+                    .frame(maxWidth: MobileLayout.homeMaximumWidth)
+                    // Short multitasking windows and the onscreen keyboard
+                    // must not squeeze the recent list below a usable height.
+                    .frame(height: max(isWide ? 260 : 420, proxy.size.height - 36),
+                           alignment: .top)
+                    .frame(maxWidth: .infinity)
+                    .padding(.horizontal, 20)
                     .padding(.top, 24)
-                recentConnectionsPanel
-                    .padding(.top, 20)
-                    .frame(maxHeight: .infinity)
+                    .padding(.bottom, 12)
+                }
+                .scrollDismissesKeyboard(.interactively)
             }
-            .padding(.horizontal, 20)
-            .padding(.bottom, 12)
 
             if session.isConnecting {
                 connectionProgressOverlay
@@ -430,7 +464,7 @@ private struct ConnectionHomeView: View {
     }
 
     @ViewBuilder
-    private var recentConnectionsPanel: some View {
+    private func recentConnectionsPanel(windowWidth: CGFloat) -> some View {
         VStack(alignment: .leading, spacing: 14) {
             HStack(alignment: .firstTextBaseline) {
                 Text("最近连接")
@@ -458,7 +492,7 @@ private struct ConnectionHomeView: View {
                 .frame(maxWidth: .infinity, maxHeight: .infinity)
             } else {
                 ScrollView(.vertical) {
-                    LazyVGrid(columns: recentConnectionColumns, spacing: 12) {
+                    LazyVGrid(columns: recentConnectionColumns(windowWidth: windowWidth), spacing: 12) {
                         ForEach(orderedRecentConnections) { connection in
                             RecentConnectionCard(
                                 connection: connection,
@@ -872,6 +906,8 @@ private struct ServerSettingsView: View {
                 .accessibilityLabel(appUpdates.updateAvailable ? "关于，有新版本" : "关于")
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("设置")
         .navigationBarTitleDisplayMode(.inline)
         .scrollDismissesKeyboard(.interactively)

apps/ios/CrossDeskMobile/CrossDeskMobileApp.swift

@@ -2,7 +2,8 @@ import SwiftUI
 import UIKit
 
 final class CrossDeskAppDelegate: NSObject, UIApplicationDelegate {
-    static var supportedOrientations: UIInterfaceOrientationMask = .portrait
+    static var supportedOrientations: UIInterfaceOrientationMask =
+        UIDevice.current.userInterfaceIdiom == .pad ? .all : .portrait
 
     func application(_ application: UIApplication,
                      supportedInterfaceOrientationsFor window: UIWindow?)
@@ -14,6 +15,10 @@ final class CrossDeskAppDelegate: NSObject, UIApplicationDelegate {
 enum AppOrientation {
     static func update(to orientations: UIInterfaceOrientationMask) {
         DispatchQueue.main.async {
+            // iPad windows can rotate and resize independently of the session.
+            // Keep all orientations available and let the window manager choose
+            // the geometry; the phone still locks the home screen to portrait.
+            guard UIDevice.current.userInterfaceIdiom != .pad else { return }
             CrossDeskAppDelegate.supportedOrientations = orientations
 
             for case let scene as UIWindowScene in UIApplication.shared.connectedScenes {

apps/ios/CrossDeskMobile/PrivacyViews.swift

@@ -10,6 +10,7 @@ struct PrivacyConsentView: View {
                 PrivacyPolicyDocument()
                     .padding(.horizontal, 20)
                     .padding(.vertical, 20)
+                    .readableContentWidth()
             }
             .background(Color(.systemBackground))
             .safeAreaInset(edge: .bottom, spacing: 0) {
@@ -57,6 +58,7 @@ struct PrivacyConsentView: View {
             }
             .padding(.horizontal, 20)
             .padding(.vertical, 12)
+            .readableContentWidth()
         }
         .background(Color(.systemBackground))
     }
@@ -161,6 +163,8 @@ private struct PrivacyAuthorizationView: View {
                 }
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("隐私与授权")
         .navigationBarTitleDisplayMode(.inline)
         .alert("是否撤回隐私授权？", isPresented: $confirmWithdrawal) {
@@ -220,7 +224,7 @@ private struct PrivacyPolicyDocument: View {
 struct PrivacyPolicyView: View {
     var body: some View {
         ScrollView {
-            PrivacyPolicyDocument().padding()
+            PrivacyPolicyDocument().padding().readableContentWidth()
         }
         .navigationTitle("隐私政策")
         .navigationBarTitleDisplayMode(.inline)

apps/ios/CrossDeskMobile/ThirdPartyLicensesView.swift

@@ -138,6 +138,8 @@ struct ThirdPartyLicensesView: View {
                 .padding()
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("关于 CrossDesk")
         .navigationBarTitleDisplayMode(.inline)
         .onChange(of: session.hasNetworkConsent) { allowed in
@@ -189,6 +191,8 @@ private struct OpenSourceComponentsView: View {
                 Text("各组件遵循所列开源许可证，其授予的权利不受本应用普通使用条款限制。查看源码需要网络连接。")
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("开源组件")
         .navigationBarTitleDisplayMode(.inline)
     }
@@ -217,6 +221,8 @@ private struct SourceCodeView: View {
                 }
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle("源码与构建说明")
         .navigationBarTitleDisplayMode(.inline)
     }
@@ -240,6 +246,7 @@ private struct ComponentLicenseView: View {
                 ForEach(component.documents) { document in
                     NavigationLink {
                         LicenseTextView(text: document.text)
+                            .readableContentWidth()
                             .navigationTitle(documentTitle(document.title))
                             .navigationBarTitleDisplayMode(.inline)
                     } label: {
@@ -248,6 +255,8 @@ private struct ComponentLicenseView: View {
                 }
             }
         }
+        .readableContentWidth()
+        .background(Color(.systemGroupedBackground).ignoresSafeArea())
         .navigationTitle(component.name)
         .navigationBarTitleDisplayMode(.inline)
     }

apps/ios/README.md

@@ -148,6 +148,17 @@ No Apple signing secrets are needed. Sign the app yourself before installing
 it on a device. Push any referenced MiniRTC commit before the parent repository
 so the runner can check out all corresponding sources.
 
+## iPad and adaptive layout
+
+iPad supports portrait, upside-down portrait, landscape and resizable multitasking
+windows on both the home screen and an active remote session. The home screen
+uses two columns at a window width of 900 points or more, with the connection
+form beside recent connections; smaller windows use a single column. Content is
+centered at a maximum width of 1200 points, and recent-connection cards adapt to
+the available space. Settings and reading pages are limited to 720 points.
+Resizing preserves the connection fields and active session. iPhone retains its
+portrait home screen and two-column recent-connection grid.
+
 ## App updates
 
 After network consent, the app checks the public version manifest once on each