diff --git a/Bin/SunnyUI.dll b/Bin/SunnyUI.dll
index 00742811..2bd43d8d 100644
Binary files a/Bin/SunnyUI.dll and b/Bin/SunnyUI.dll differ
diff --git a/Bin/SunnyUI.pdb b/Bin/SunnyUI.pdb
index 2159528a..c334cc93 100644
Binary files a/Bin/SunnyUI.pdb and b/Bin/SunnyUI.pdb differ
diff --git a/SunnyUI.Demo/Bin/SunnyUI.Demo.exe b/SunnyUI.Demo/Bin/SunnyUI.Demo.exe
index 678729a8..8b59a504 100644
Binary files a/SunnyUI.Demo/Bin/SunnyUI.Demo.exe and b/SunnyUI.Demo/Bin/SunnyUI.Demo.exe differ
diff --git a/SunnyUI.Demo/Bin/SunnyUI.dll b/SunnyUI.Demo/Bin/SunnyUI.dll
index 00742811..2bd43d8d 100644
Binary files a/SunnyUI.Demo/Bin/SunnyUI.dll and b/SunnyUI.Demo/Bin/SunnyUI.dll differ
diff --git a/SunnyUI.Demo/Controls/FTransfer.Designer.cs b/SunnyUI.Demo/Controls/FTransfer.Designer.cs
index a7814f68..475b3ac6 100644
--- a/SunnyUI.Demo/Controls/FTransfer.Designer.cs
+++ b/SunnyUI.Demo/Controls/FTransfer.Designer.cs
@@ -37,6 +37,7 @@
             // 
             this.PagePanel.Controls.Add(this.uiLine1);
             this.PagePanel.Controls.Add(this.uiTransfer1);
+            this.PagePanel.Size = new System.Drawing.Size(800, 480);
             // 
             // uiTransfer1
             // 
@@ -68,6 +69,8 @@
             this.uiTransfer1.Size = new System.Drawing.Size(427, 370);
             this.uiTransfer1.TabIndex = 3;
             this.uiTransfer1.Text = "uiTransfer1";
+            this.uiTransfer1.ItemsLeftCountChange += new System.EventHandler(this.uiTransfer1_ItemsLeftCountChange);
+            this.uiTransfer1.ItemsRightCountChange += new System.EventHandler(this.uiTransfer1_ItemsRightCountChange);
             // 
             // uiLine1
             // 
@@ -84,7 +87,7 @@
             // 
             this.AutoScaleDimensions = new System.Drawing.SizeF(10F, 21F);
             this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
-            this.ClientSize = new System.Drawing.Size(800, 450);
+            this.ClientSize = new System.Drawing.Size(800, 515);
             this.Name = "FTransfer";
             this.Symbol = 61516;
             this.Text = "Transfer";
diff --git a/SunnyUI.Demo/Controls/FTransfer.cs b/SunnyUI.Demo/Controls/FTransfer.cs
index 5bf5e86a..20e3a906 100644
--- a/SunnyUI.Demo/Controls/FTransfer.cs
+++ b/SunnyUI.Demo/Controls/FTransfer.cs
@@ -1,4 +1,6 @@
-namespace Sunny.UI.Demo
+using System;
+
+namespace Sunny.UI.Demo
 {
     public partial class FTransfer : UITitlePage
     {
@@ -6,5 +8,15 @@
         {
             InitializeComponent();
         }
+
+        private void uiTransfer1_ItemsLeftCountChange(object sender, System.EventArgs e)
+        {
+            Console.WriteLine("Left: " + uiTransfer1.ItemsLeft.Count);
+        }
+
+        private void uiTransfer1_ItemsRightCountChange(object sender, System.EventArgs e)
+        {
+            Console.WriteLine("Right: " + uiTransfer1.ItemsRight.Count);
+        }
     }
 }
diff --git a/SunnyUI/Controls/UIListBox.cs b/SunnyUI/Controls/UIListBox.cs
index 291be117..49fd3203 100644
--- a/SunnyUI/Controls/UIListBox.cs
+++ b/SunnyUI/Controls/UIListBox.cs
@@ -37,6 +37,7 @@ namespace Sunny.UI
     {
         private readonly ListBoxEx listbox = new ListBoxEx();
         private readonly UIScrollBar bar = new UIScrollBar();
+        private readonly Timer timer = new Timer();
 
         public UIListBox()
         {
@@ -61,6 +62,25 @@ namespace Sunny.UI
             listbox.Click += Listbox_Click;
             listbox.DoubleClick += Listbox_DoubleClick;
             listbox.BeforeDrawItem += Listbox_BeforeDrawItem;
+
+            timer.Tick += Timer_Tick;
+            timer.Start();
+        }
+
+        ~UIListBox()
+        {
+            timer.Stop();
+        }
+
+        private void Timer_Tick(object sender, EventArgs e)
+        {
+            if (Items.Count == 0 && LastCount != 0)
+            {
+                LastCount = 0;
+                timer.Stop();
+                ItemsCountChange?.Invoke(sender, e);
+                timer.Start();
+            }
         }
 
         protected override void OnFontChanged(EventArgs e)
diff --git a/SunnyUI/Controls/UITransfer.cs b/SunnyUI/Controls/UITransfer.cs
index d04ecf83..488faa24 100644
--- a/SunnyUI/Controls/UITransfer.cs
+++ b/SunnyUI/Controls/UITransfer.cs
@@ -39,8 +39,23 @@ namespace Sunny.UI
         {
             InitializeComponent();
             ShowText = false;
+
+            l1.ItemsCountChange += L1_ItemsCountChange;
+            l2.ItemsCountChange += L2_ItemsCountChange;
         }
 
+        private void L2_ItemsCountChange(object sender, EventArgs e)
+        {
+            ItemsRightCountChange?.Invoke(sender, e);
+        }
+
+        private void L1_ItemsCountChange(object sender, EventArgs e)
+        {
+            ItemsLeftCountChange?.Invoke(sender, e);
+        }
+
+        public event EventHandler ItemsLeftCountChange;
+        public event EventHandler ItemsRightCountChange;
         /// <summary>
         /// 左侧列表
         /// </summary>