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Ink Canvas/MainWindow_cs/MW_TrayIcon.cs

@@ -87,7 +87,7 @@ namespace Ink_Canvas
         private void SysTrayMenu_Closed(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 // 菜单关闭后，恢复主窗口的置顶状态
                 if (Ink_Canvas.MainWindow.Settings.Advanced.IsAlwaysOnTop && Ink_Canvas.MainWindow.Settings.Advanced.IsNoFocusMode)
@@ -112,7 +112,7 @@ namespace Ink_Canvas
         private void CloseAppTrayIconMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 IsAppExitByUser = true;
                 mainWin.BtnExit_Click(null, null);
@@ -136,7 +136,7 @@ namespace Ink_Canvas
         private void RestartAppTrayIconMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 IsAppExitByUser = true;
 
@@ -176,7 +176,7 @@ namespace Ink_Canvas
         private void ForceFullScreenTrayIconMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 Ink_Canvas.MainWindow.MoveWindow(new WindowInteropHelper(mainWin).Handle, 0, 0,
                     Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, true);
@@ -199,7 +199,7 @@ namespace Ink_Canvas
         private void FoldFloatingBarTrayIconMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
                 if (mainWin.isFloatingBarFolded) mainWin.UnFoldFloatingBar_MouseUp(new object(), null);
                 else mainWin.FoldFloatingBar_MouseUp(new object(), null);
         }
@@ -221,7 +221,7 @@ namespace Ink_Canvas
         private void ResetFloatingBarPositionTrayIconMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 var isInPPTPresentationMode = false;
                 Dispatcher.Invoke(() =>
@@ -257,19 +257,22 @@ namespace Ink_Canvas
         {
             var mi = (MenuItem)sender;
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 mainWin.Hide();
                 var s = ((TaskbarIcon)Current.Resources["TaskbarTrayIcon"]).ContextMenu;
-                var ResetFloatingBarPositionTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 4];
+                if (s != null)
-                var FoldFloatingBarTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 5];
+                {
-                var ForceFullScreenTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 6];
+                    var ResetFloatingBarPositionTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 4];
-                ResetFloatingBarPositionTrayIconMenuItem.IsEnabled = false;
+                    var FoldFloatingBarTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 5];
-                FoldFloatingBarTrayIconMenuItem.IsEnabled = false;
+                    var ForceFullScreenTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 6];
-                ForceFullScreenTrayIconMenuItem.IsEnabled = false;
+                    ResetFloatingBarPositionTrayIconMenuItem.IsEnabled = false;
-                ResetFloatingBarPositionTrayIconMenuItem.Opacity = 0.5;
+                    FoldFloatingBarTrayIconMenuItem.IsEnabled = false;
-                FoldFloatingBarTrayIconMenuItem.Opacity = 0.5;
+                    ForceFullScreenTrayIconMenuItem.IsEnabled = false;
-                ForceFullScreenTrayIconMenuItem.Opacity = 0.5;
+                    ResetFloatingBarPositionTrayIconMenuItem.Opacity = 0.5;
+                    FoldFloatingBarTrayIconMenuItem.Opacity = 0.5;
+                    ForceFullScreenTrayIconMenuItem.Opacity = 0.5;
+                }
             }
             else
             {
@@ -299,19 +302,22 @@ namespace Ink_Canvas
         {
             var mi = (MenuItem)sender;
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 mainWin.Show();
                 var s = ((TaskbarIcon)Current.Resources["TaskbarTrayIcon"]).ContextMenu;
-                var ResetFloatingBarPositionTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 4];
+                if (s != null)
-                var FoldFloatingBarTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 5];
+                {
-                var ForceFullScreenTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 6];
+                    var ResetFloatingBarPositionTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 4];
-                ResetFloatingBarPositionTrayIconMenuItem.IsEnabled = true;
+                    var FoldFloatingBarTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 5];
-                FoldFloatingBarTrayIconMenuItem.IsEnabled = true;
+                    var ForceFullScreenTrayIconMenuItem = (MenuItem)s.Items[s.Items.Count - 6];
-                ForceFullScreenTrayIconMenuItem.IsEnabled = true;
+                    ResetFloatingBarPositionTrayIconMenuItem.IsEnabled = true;
-                ResetFloatingBarPositionTrayIconMenuItem.Opacity = 1;
+                    FoldFloatingBarTrayIconMenuItem.IsEnabled = true;
-                FoldFloatingBarTrayIconMenuItem.Opacity = 1;
+                    ForceFullScreenTrayIconMenuItem.IsEnabled = true;
-                ForceFullScreenTrayIconMenuItem.Opacity = 1;
+                    ResetFloatingBarPositionTrayIconMenuItem.Opacity = 1;
+                    FoldFloatingBarTrayIconMenuItem.Opacity = 1;
+                    ForceFullScreenTrayIconMenuItem.Opacity = 1;
+                }
             }
             else
             {
@@ -340,7 +346,7 @@ namespace Ink_Canvas
         private void DisableAllHotkeysMenuItem_Clicked(object sender, RoutedEventArgs e)
         {
             var mainWin = (MainWindow)Current.MainWindow;
-            if (mainWin.IsLoaded)
+            if (mainWin != null && mainWin.IsLoaded)
             {
                 try
                 {

Ink Canvas/Windows/MinimizedTimerControl.xaml.cs

@@ -2,6 +2,7 @@ using iNKORE.UI.WPF.Modern;
 using Microsoft.Win32;
 using System;
 using System.Timers;
+using System.Windows.Threading;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
@@ -17,11 +18,16 @@ namespace Ink_Canvas.Windows
     {
         private TimerControl parentControl;
         private System.Timers.Timer updateTimer;
+        private readonly Dispatcher uiDispatcher;
 
         public MinimizedTimerControl()
         {
             InitializeComponent();
 
+            // capture the UI dispatcher early so timer callbacks can use it even when
+            // Application.Current may become null during shutdown
+            uiDispatcher = this.Dispatcher;
+
             updateTimer = new System.Timers.Timer(100);
             updateTimer.Elapsed += UpdateTimer_Elapsed;
             updateTimer.Start();
@@ -46,18 +52,35 @@ namespace Ink_Canvas.Windows
 
             if (updateTimer != null)
             {
-                updateTimer.Stop();
+                // 先取消事件订阅，防止在停止/释放后仍有回调被触发
-                updateTimer.Dispose();
+                updateTimer.Elapsed -= UpdateTimer_Elapsed;
+                try
+                {
+                    updateTimer.Stop();
+                }
+                catch { }
+                try
+                {
+                    updateTimer.Dispose();
+                }
+                catch { }
+                updateTimer = null;
             }
         }
 
         private void SystemEvents_UserPreferenceChanged(object sender, UserPreferenceChangedEventArgs e)
         {
             // 当主题变化时，重新应用主题
-            Application.Current.Dispatcher.Invoke(() =>
+            var dispatcher = uiDispatcher ?? Application.Current?.Dispatcher;
+            if (dispatcher == null) return;
+            if (dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+            // 使用异步调用，避免在关闭过程中同步等待导致异常
+            try
             {
-                RefreshTheme();
+                dispatcher.InvokeAsync(() => RefreshTheme(), DispatcherPriority.Normal);
-            });
+            }
+            catch { }
         }
 
         /// <summary>
@@ -99,26 +122,35 @@ namespace Ink_Canvas.Windows
         {
             if (parentControl != null)
             {
-                Application.Current.Dispatcher.Invoke(() =>
+                var dispatcher = uiDispatcher ?? Application.Current?.Dispatcher;
+                if (dispatcher == null) return;
+                if (dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+                // 使用异步派发，避免在 Dispatcher 关闭时同步等待导致 TaskCanceledException
+                try
                 {
-                    if (this.Visibility != Visibility.Visible)
+                    dispatcher.InvokeAsync(() =>
                     {
-                        return;
+                        if (this.Visibility != Visibility.Visible)
-                    }
-
-                    if (ShouldHide())
-                    {
-                        this.Visibility = Visibility.Collapsed;
-                        var parent = this.Parent as FrameworkElement;
-                        if (parent != null)
                         {
-                            parent.Visibility = Visibility.Collapsed;
+                            return;
                         }
-                        return;
-                    }
 
-                    UpdateTimeDisplay();
+                        if (ShouldHide())
-                });
+                        {
+                            this.Visibility = Visibility.Collapsed;
+                            var parent = this.Parent as FrameworkElement;
+                            if (parent != null)
+                            {
+                                parent.Visibility = Visibility.Collapsed;
+                            }
+                            return;
+                        }
+
+                        UpdateTimeDisplay();
+                    }, DispatcherPriority.Normal);
+                }
+                catch { }
             }
         }
 
@@ -214,10 +246,15 @@ namespace Ink_Canvas.Windows
 
         private void ParentControl_TimerCompleted(object sender, EventArgs e)
         {
-            Application.Current.Dispatcher.Invoke(() =>
+            var dispatcher = uiDispatcher ?? Application.Current?.Dispatcher;
+            if (dispatcher == null) return;
+            if (dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+            try
             {
-                Visibility = Visibility.Collapsed;
+                dispatcher.InvokeAsync(() => { Visibility = Visibility.Collapsed; }, DispatcherPriority.Normal);
-            });
+            }
+            catch { }
         }
 
         private void SetDigitDisplay(string pathName, int digit, bool isRed = false)
@@ -391,7 +428,7 @@ namespace Ink_Canvas.Windows
         {
             try
             {
-                var mainWindow = Application.Current.MainWindow as MainWindow;
+                var mainWindow = Application.Current?.MainWindow as MainWindow;
                 if (mainWindow != null)
                 {
                     var currentModeField = mainWindow.GetType().GetField("currentMode",

Ink Canvas/Windows/OobeWindow.xaml

@@ -5,8 +5,8 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         mc:Ignorable="d"
         Title="欢迎使用 InkCanvasForClass"
-        Height="460"
+        Height="480"
-        Width="780"
+        Width="800"
         MinHeight="300"
         MinWidth="400"
         WindowStartupLocation="CenterScreen"

Ink Canvas/Windows/PPTTimeCapsule.xaml.cs

@@ -28,6 +28,7 @@ namespace Ink_Canvas.Windows
         private double originalCapsuleWidth = 0;
         private string lastCountdownText = ""; // 上次的倒计时文本，用于检测文本变化
         private Storyboard currentWidthAnimation; // 当前正在运行的宽度动画
+        private volatile bool isDisposed = false;
 
         public PPTTimeCapsule()
         {
@@ -72,10 +73,43 @@ namespace Ink_Canvas.Windows
         /// </summary>
         public void Dispose()
         {
-            StopTimeUpdate();
+            if (isDisposed) return;
-            SystemEvents.UserPreferenceChanged -= SystemEvents_UserPreferenceChanged;
+            isDisposed = true;
-            timeUpdateTimer?.Dispose();
+
-            countdownUpdateTimer?.Dispose();
+            // 先取消系统事件订阅，防止在释放过程中再次触发
+            try
+            {
+                SystemEvents.UserPreferenceChanged -= SystemEvents_UserPreferenceChanged;
+            }
+            catch { }
+
+            // 停止并释放定时器，确保不再触发回调
+            try
+            {
+                if (timeUpdateTimer != null)
+                {
+                    timeUpdateTimer.Elapsed -= TimeUpdateTimer_Elapsed;
+                    try { timeUpdateTimer.Stop(); } catch { }
+                    try { timeUpdateTimer.Dispose(); } catch { }
+                    timeUpdateTimer = null;
+                }
+            }
+            catch { }
+
+            try
+            {
+                if (countdownUpdateTimer != null)
+                {
+                    countdownUpdateTimer.Elapsed -= CountdownUpdateTimer_Elapsed;
+                    try { countdownUpdateTimer.Stop(); } catch { }
+                    try { countdownUpdateTimer.Dispose(); } catch { }
+                    countdownUpdateTimer = null;
+                }
+            }
+            catch { }
+
+            // 停止动画
+            try { StopColonBlinkAnimation(); } catch { }
         }
 
         private void InitializeTimers()
@@ -91,23 +125,39 @@ namespace Ink_Canvas.Windows
 
         private void TimeUpdateTimer_Elapsed(object sender, ElapsedEventArgs e)
         {
-            Application.Current.Dispatcher.BeginInvoke(new Action(() =>
+            if (isDisposed) return;
+
+            var dispatcher = this.Dispatcher;
+            if (dispatcher == null || dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+            try
             {
-                UpdateTimeDisplay();
+                dispatcher.BeginInvoke(new Action(() =>
-            }), DispatcherPriority.Normal);
+                {
+                    if (isDisposed) return;
+                    UpdateTimeDisplay();
+                }), DispatcherPriority.Normal);
+            }
+            catch { }
         }
 
         private void CountdownUpdateTimer_Elapsed(object sender, ElapsedEventArgs e)
         {
-            Application.Current.Dispatcher.BeginInvoke(new Action(() =>
+            if (isDisposed) return;
-            {
-                if (this.Visibility != Visibility.Visible)
-                {
-                    return;
-                }
 
-                UpdateCountdownDisplay();
+            var dispatcher = this.Dispatcher;
-            }), DispatcherPriority.Normal);
+            if (dispatcher == null || dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+            try
+            {
+                dispatcher.BeginInvoke(new Action(() =>
+                {
+                    if (isDisposed) return;
+                    if (this.Visibility != Visibility.Visible) return;
+                    UpdateCountdownDisplay();
+                }), DispatcherPriority.Normal);
+            }
+            catch { }
         }
 
         private void StartTimeUpdate()
@@ -724,10 +774,20 @@ namespace Ink_Canvas.Windows
 
         private void SystemEvents_UserPreferenceChanged(object sender, UserPreferenceChangedEventArgs e)
         {
-            Application.Current.Dispatcher.BeginInvoke(new Action(() =>
+            if (isDisposed) return;
+
+            var dispatcher = this.Dispatcher;
+            if (dispatcher == null || dispatcher.HasShutdownStarted || dispatcher.HasShutdownFinished) return;
+
+            try
             {
-                ApplyTheme();
+                dispatcher.BeginInvoke(new Action(() =>
-            }), DispatcherPriority.Normal);
+                {
+                    if (isDisposed) return;
+                    ApplyTheme();
+                }), DispatcherPriority.Normal);
+            }
+            catch { }
         }
 
         private void ApplyTheme()