* UIForm: 多页面框架增加PageAdded，PageSelected，PageRemoved事件

SunnyUI/Controls/UITabControl.cs

@@ -77,6 +77,12 @@ namespace Sunny.UI
             _fillColor = UIStyles.Blue.TabControlBackColor;
         }
 
+        [Browsable(false)]
+        public IFrame Frame
+        {
+            get; set;
+        }
+
         /// <summary>
         /// 禁止控件跟随窗体缩放
         /// </summary>
@@ -235,8 +241,6 @@ namespace Sunny.UI
 
         public bool SelectPage(Guid pageGuid) => Helper.SelectPage(pageGuid);
 
-        public void AddPage(UIPage page) => Helper.AddPage(page);
-
         public bool RemovePage(int pageIndex) => Helper.RemovePage(pageIndex);
 
         public bool RemovePage(Guid guid) => Helper.RemovePage(guid);
@@ -254,6 +258,12 @@ namespace Sunny.UI
             foreach (var page in pages) AddPage(page);
         }
 
+        public void AddPage(UIPage page)
+        {
+            Helper.AddPage(page);
+            Frame?.DealPageAdded(page);
+        }
+
         public void AddPage(int pageIndex, UITabControl page) => Helper.AddPage(pageIndex, page);
 
         public void AddPage(int pageIndex, UITabControlMenu page) => Helper.AddPage(pageIndex, page);
@@ -840,10 +850,17 @@ namespace Sunny.UI
             {
                 if (AutoClosePage)
                 {
-                    pages[i].Final();
+                    Frame.DealPageRemoved(pages[i]);
-                    pages[i].Close();
+
-                    pages[i].Dispose();
+                    try
-                    pages[i] = null;
+                    {
+                        pages[i].Final();
+                        pages[i].Close();
+                        pages[i].Dispose();
+                        pages[i] = null;
+                    }
+                    catch
+                    { }
                 }
                 else
                 {

SunnyUI/Forms/UIForm.cs

@@ -35,6 +35,7 @@
  * 2022-04-26: V3.1.8 屏蔽一些属性
  * 2022-05-06: V3.1.8 可拖拽时Padding可以调整大小
  * 2022-06-11: V3.1.9 弹窗默认关闭半透明遮罩
+ * 2022-07-05: V3.2.1 多页面框架增加PageAdded，PageSelected，PageRemoved事件
 ******************************************************************************/
 
 using System;
@@ -2072,7 +2073,18 @@ namespace Sunny.UI
 
         #region IFrame实现
 
-        public UITabControl MainTabControl { get; set; }
+        private UITabControl mainTabControl;
+
+        [DefaultValue(null)]
+        public UITabControl MainTabControl
+        {
+            get => mainTabControl;
+            set
+            {
+                mainTabControl = value;
+                mainTabControl.Frame = this;
+            }
+        }
 
         public UIPage AddPage(UIPage page, int index)
         {
@@ -2089,6 +2101,12 @@ namespace Sunny.UI
         public UIPage AddPage(UIPage page)
         {
             SetDefaultTabControl();
+
+            if (MainTabControl == null)
+            {
+                throw (new ApplicationException("未指定MainTabControl，无法承载多页面。"));
+            }
+
             page.Frame = this;
             MainTabControl?.AddPage(page);
             return page;
@@ -2168,6 +2186,25 @@ namespace Sunny.UI
 
         public List<T> GetPages<T>() where T : UIPage => SetDefaultTabControl().MainTabControl?.GetPages<T>();
 
+        public event OnUIPageChanged PageAdded;
+
+        public void DealPageAdded(UIPage page)
+        {
+            PageAdded?.Invoke(this, new UIPageEventArgs(page));
+        }
+
+        public event OnUIPageChanged PageSelected;
+        public void DealPageSelected(UIPage page)
+        {
+            PageSelected?.Invoke(this, new UIPageEventArgs(page));
+        }
+
+        public event OnUIPageChanged PageRemoved;
+        public void DealPageRemoved(UIPage page)
+        {
+            PageRemoved?.Invoke(this, new UIPageEventArgs(page));
+        }
+
         #endregion IFrame实现
     }
 }

SunnyUI/Forms/UIFormHelper.cs

@@ -34,6 +34,23 @@ namespace Sunny.UI
 
     public delegate void OnZoomScaleRectChanged(object sender, Rectangle info);
 
+    public class UIPageEventArgs : EventArgs
+    {
+        public UIPage Page { get; set; }
+
+        public UIPageEventArgs()
+        {
+
+        }
+
+        public UIPageEventArgs(UIPage page)
+        {
+            Page = page;
+        }
+    }
+
+    public delegate void OnUIPageChanged(object sender, UIPageEventArgs e);
+
     public static class UIMessageDialog
     {
         /// <summary>

SunnyUI/Frames/IFrame.cs

@@ -65,5 +65,9 @@ namespace Sunny.UI
         T GetPage<T>() where T : UIPage;
 
         List<T> GetPages<T>() where T : UIPage;
+
+        void DealPageAdded(UIPage page);
+        void DealPageSelected(UIPage page);
+        void DealPageRemoved(UIPage page);
     }
 }

SunnyUI/Frames/UIPage.cs

@@ -454,6 +454,7 @@ namespace Sunny.UI
         public virtual void Init()
         {
             Initialize?.Invoke(this, new EventArgs());
+            Frame.DealPageSelected(this);
         }
 
         protected override void OnLoad(EventArgs e)