修改触发器相关的内容

DMS.WPF/Converters/EmptyCollectionToVisibilityConverter.cs

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+using System;
+using System.Collections;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace DMS.WPF.Converters
+{
+    /// <summary>
+    /// 当集合为空时返回Visibility.Visible，否则返回Visibility.Collapsed
+    /// </summary>
+    public class EmptyCollectionToVisibilityConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            if (value is ICollection collection)
+            {
+                return collection.Count == 0 ? Visibility.Visible : Visibility.Collapsed;
+            }
+            
+            return Visibility.Visible;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}