优化更新代码，添加界面功能并整合

WPFluent/Controls/Snackbar/SnackbarPresenter.cs

@@ -0,0 +1,153 @@
+
+
+
+// ReSharper disable once CheckNamespace
+namespace WPFluent.Controls;
+
+public class SnackbarPresenter : System.Windows.Controls.ContentPresenter
+{
+    public SnackbarPresenter()
+    {
+        Unloaded += static(sender, _) =>
+        {
+            var self = (SnackbarPresenter)sender;
+            self.OnUnloaded();
+        };
+    }
+
+    ~SnackbarPresenter()
+    {
+        if(!CancellationTokenSource.IsCancellationRequested)
+        {
+            CancellationTokenSource.Cancel();
+        }
+
+        CancellationTokenSource.Dispose();
+    }
+
+    [System.Diagnostics.CodeAnalysis.SuppressMessage(
+        "WpfAnalyzers.DependencyProperty",
+        "WPF0041:Set mutable dependency properties using SetCurrentValue",
+        Justification = "SetCurrentValue(ContentProperty, ...) will not work")]
+    private async Task HidSnackbar(Snackbar snackbar)
+    {
+        snackbar.SetCurrentValue(Snackbar.IsShownProperty, false);
+
+        await Task.Delay(300);
+
+        Content = null;
+    }
+
+    private void ImmediatelyHideCurrent()
+    {
+        if(Content is null)
+        {
+            return;
+        }
+
+        CancellationTokenSource.Cancel();
+        ImmediatelyHidSnackbar(Content);
+    }
+
+    [System.Diagnostics.CodeAnalysis.SuppressMessage(
+        "WpfAnalyzers.DependencyProperty",
+        "WPF0041:Set mutable dependency properties using SetCurrentValue",
+        Justification = "SetCurrentValue(ContentProperty, ...) will not work")]
+    private void ImmediatelyHidSnackbar(Snackbar snackbar)
+    {
+        snackbar.SetCurrentValue(Snackbar.IsShownProperty, false);
+        Content = null;
+    }
+
+    private async Task ShowQueuedSnackbarsAsync()
+    {
+        while(Queue.Count > 0 && !CancellationTokenSource.IsCancellationRequested)
+        {
+            Snackbar snackbar = Queue.Dequeue();
+
+            await ShowSnackbar(snackbar);
+        }
+    }
+
+    [System.Diagnostics.CodeAnalysis.SuppressMessage(
+        "WpfAnalyzers.DependencyProperty",
+        "WPF0041:Set mutable dependency properties using SetCurrentValue",
+        Justification = "SetCurrentValue(ContentProperty, ...) will not work")]
+    private async Task ShowSnackbar(Snackbar snackbar)
+    {
+        Content = snackbar;
+
+        snackbar.SetCurrentValue(Snackbar.IsShownProperty, true);
+
+        try
+        {
+            await Task.Delay(snackbar.Timeout, CancellationTokenSource.Token);
+        } catch
+        {
+            return;
+        }
+
+        await HidSnackbar(snackbar);
+    }
+
+    protected virtual void OnUnloaded()
+    {
+        if(CancellationTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
+        ImmediatelyHideCurrent();
+        ResetCancellationTokenSource();
+    }
+
+    protected void ResetCancellationTokenSource()
+    {
+        CancellationTokenSource.Dispose();
+        CancellationTokenSource = new CancellationTokenSource();
+    }
+
+    protected CancellationTokenSource CancellationTokenSource { get; set; } = new();
+
+    protected Queue<Snackbar> Queue { get; } = new();
+
+    public virtual void AddToQue(Snackbar snackbar)
+    {
+        Queue.Enqueue(snackbar);
+
+        if(Content is null)
+        {
+            _ = ShowQueuedSnackbarsAsync(); // TODO: Fix detached process
+        }
+    }
+
+    public virtual async Task HideCurrent()
+    {
+        if(Content is null)
+        {
+            return;
+        }
+
+        CancellationTokenSource.Cancel();
+        await HidSnackbar(Content);
+        ResetCancellationTokenSource();
+    }
+
+    public virtual async Task ImmediatelyDisplay(Snackbar snackbar)
+    {
+        await HideCurrent();
+        await ShowSnackbar(snackbar);
+
+        await ShowQueuedSnackbarsAsync();
+    }
+
+    [System.Diagnostics.CodeAnalysis.SuppressMessage(
+        "WpfAnalyzers.DependencyProperty",
+        "WPF0012:CLR property type should match registered type",
+        Justification = "seems harmless")]
+    public new Snackbar? Content
+    {
+        get => (Snackbar?)GetValue(ContentProperty);
+        protected set => SetValue(ContentProperty, value);
+    }
+}