Move sub-classes of "NotifyIcon", "ToolStripDropDownItem", "ToolStripSplitButton" and "ToolStripStatusLabel" classes to their own files (#4612)

Author: SergeySmirnov-Akvelon

src/System.Windows.Forms/src/System/Windows/Forms/NotifyIcon.NotifyIconNativeWindow.cs

@@ -0,0 +1,78 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#nullable disable
+
+using System.Diagnostics;
+using System.Runtime.InteropServices;
+using static Interop;
+
+namespace System.Windows.Forms
+{
+    public sealed partial class NotifyIcon
+    {
+        /// <summary>
+        ///  Defines a placeholder window that the NotifyIcon is attached to.
+        /// </summary>
+        private class NotifyIconNativeWindow : NativeWindow
+        {
+            internal NotifyIcon reference;
+            private GCHandle rootRef;   // We will root the control when we do not want to be elligible for garbage collection.
+
+            /// <summary>
+            ///  Create a new NotifyIcon, and bind the window to the NotifyIcon component.
+            /// </summary>
+            internal NotifyIconNativeWindow(NotifyIcon component)
+            {
+                reference = component;
+            }
+
+            ~NotifyIconNativeWindow()
+            {
+                // This same post is done in Control's Dispose method, so if you change
+                // it, change it there too.
+                //
+                if (Handle != IntPtr.Zero)
+                {
+                    User32.PostMessageW(this, User32.WM.CLOSE);
+                }
+
+                // This releases the handle from our window proc, re-routing it back to
+                // the system.
+            }
+
+            public void LockReference(bool locked)
+            {
+                if (locked)
+                {
+                    if (!rootRef.IsAllocated)
+                    {
+                        rootRef = GCHandle.Alloc(reference, GCHandleType.Normal);
+                    }
+                }
+                else
+                {
+                    if (rootRef.IsAllocated)
+                    {
+                        rootRef.Free();
+                    }
+                }
+            }
+
+            protected override void OnThreadException(Exception e)
+            {
+                Application.OnThreadException(e);
+            }
+
+            /// <summary>
+            ///  Pass messages on to the NotifyIcon object's wndproc handler.
+            /// </summary>
+            protected override void WndProc(ref Message m)
+            {
+                Debug.Assert(reference != null, "NotifyIcon was garbage collected while it was still visible.  How did we let that happen?");
+                reference.WndProc(ref m);
+            }
+        }
+    }
+}

src/System.Windows.Forms/src/System/Windows/Forms/NotifyIcon.cs

@@ -5,9 +5,7 @@
 #nullable disable
 
 using System.ComponentModel;
-using System.Diagnostics;
 using System.Drawing;
-using System.Runtime.InteropServices;
 using static Interop;
 using static Interop.Shell32;
 
@@ -22,7 +20,7 @@ namespace System.Windows.Forms
     [Designer("System.Windows.Forms.Design.NotifyIconDesigner, " + AssemblyRef.SystemDesign)]
     [ToolboxItemFilter("System.Windows.Forms")]
     [SRDescription(nameof(SR.DescriptionNotifyIcon))]
-    public sealed class NotifyIcon : Component
+    public sealed partial class NotifyIcon : Component
     {
         internal const int MaxTextSize = 127;
         private static readonly object EVENT_MOUSEDOWN = new object();
@@ -817,68 +815,5 @@ private void WndProc(ref Message msg)
                     break;
             }
         }
-
-        /// <summary>
-        ///  Defines a placeholder window that the NotifyIcon is attached to.
-        /// </summary>
-        private class NotifyIconNativeWindow : NativeWindow
-        {
-            internal NotifyIcon reference;
-            private GCHandle rootRef;   // We will root the control when we do not want to be elligible for garbage collection.
-
-            /// <summary>
-            ///  Create a new NotifyIcon, and bind the window to the NotifyIcon component.
-            /// </summary>
-            internal NotifyIconNativeWindow(NotifyIcon component)
-            {
-                reference = component;
-            }
-
-            ~NotifyIconNativeWindow()
-            {
-                // This same post is done in Control's Dispose method, so if you change
-                // it, change it there too.
-                //
-                if (Handle != IntPtr.Zero)
-                {
-                    User32.PostMessageW(this, User32.WM.CLOSE);
-                }
-
-                // This releases the handle from our window proc, re-routing it back to
-                // the system.
-            }
-
-            public void LockReference(bool locked)
-            {
-                if (locked)
-                {
-                    if (!rootRef.IsAllocated)
-                    {
-                        rootRef = GCHandle.Alloc(reference, GCHandleType.Normal);
-                    }
-                }
-                else
-                {
-                    if (rootRef.IsAllocated)
-                    {
-                        rootRef.Free();
-                    }
-                }
-            }
-
-            protected override void OnThreadException(Exception e)
-            {
-                Application.OnThreadException(e);
-            }
-
-            /// <summary>
-            ///  Pass messages on to the NotifyIcon object's wndproc handler.
-            /// </summary>
-            protected override void WndProc(ref Message m)
-            {
-                Debug.Assert(reference != null, "NotifyIcon was garbage collected while it was still visible.  How did we let that happen?");
-                reference.WndProc(ref m);
-            }
-        }
     }
 }

src/System.Windows.Forms/src/System/Windows/Forms/ToolStripDropDownItem.cs

@@ -8,7 +8,6 @@
 using System.Diagnostics;
 using System.Drawing;
 using System.Windows.Forms.Layout;
-using static Interop;
 
 namespace System.Windows.Forms
 {
@@ -768,214 +767,4 @@ internal override void ToolStrip_RescaleConstants(int oldDpi, int newDpi)
             base.ToolStrip_RescaleConstants(oldDpi, newDpi);
         }
     }
-
-    public class ToolStripDropDownItemAccessibleObject : ToolStripItem.ToolStripItemAccessibleObject
-    {
-        private readonly ToolStripDropDownItem owner;
-        public ToolStripDropDownItemAccessibleObject(ToolStripDropDownItem item) : base(item)
-        {
-            owner = item;
-        }
-        public override AccessibleRole Role
-        {
-            get
-            {
-                AccessibleRole role = Owner.AccessibleRole;
-                if (role != AccessibleRole.Default)
-                {
-                    return role;
-                }
-                return AccessibleRole.MenuItem;
-            }
-        }
-
-        public override void DoDefaultAction()
-        {
-            if (Owner is ToolStripDropDownItem item && item.HasDropDownItems)
-            {
-                item.ShowDropDown();
-            }
-            else
-            {
-                base.DoDefaultAction();
-            }
-        }
-
-        internal override bool IsIAccessibleExSupported()
-        {
-            if (owner != null)
-            {
-                return true;
-            }
-            else
-            {
-                return base.IsIAccessibleExSupported();
-            }
-        }
-
-        internal override bool IsPatternSupported(UiaCore.UIA patternId)
-        {
-            if (patternId == UiaCore.UIA.ExpandCollapsePatternId && owner.HasDropDownItems)
-            {
-                return true;
-            }
-            else
-            {
-                return base.IsPatternSupported(patternId);
-            }
-        }
-
-        internal override object GetPropertyValue(UiaCore.UIA propertyID)
-        {
-            if (propertyID == UiaCore.UIA.IsOffscreenPropertyId && owner != null && owner.Owner is ToolStripDropDown)
-            {
-                return !((ToolStripDropDown)owner.Owner).Visible;
-            }
-
-            return base.GetPropertyValue(propertyID);
-        }
-
-        internal override void Expand()
-            => DoDefaultAction();
-
-        internal override void Collapse()
-        {
-            if (owner != null && owner.DropDown != null && owner.DropDown.Visible)
-            {
-                owner.DropDown.Close();
-            }
-        }
-
-        internal override UiaCore.ExpandCollapseState ExpandCollapseState
-        {
-            get
-            {
-                return owner.DropDown.Visible ? UiaCore.ExpandCollapseState.Expanded : UiaCore.ExpandCollapseState.Collapsed;
-            }
-        }
-
-        public override AccessibleObject GetChild(int index)
-        {
-            if ((owner is null) || !owner.HasDropDownItems)
-            {
-                return null;
-            }
-            return owner.DropDown.AccessibilityObject.GetChild(index);
-        }
-
-        public override int GetChildCount()
-        {
-            if ((owner is null) || !owner.HasDropDownItems)
-            {
-                return -1;
-            }
-
-            // Do not expose child items when the submenu is collapsed to prevent Narrator from announcing
-            // invisible menu items when Narrator is in item's mode (CAPSLOCK + Arrow Left/Right) or
-            // in scan mode (CAPSLOCK + Space)
-            if (ExpandCollapseState == UiaCore.ExpandCollapseState.Collapsed)
-            {
-                return 0;
-            }
-
-            if (owner.DropDown.LayoutRequired)
-            {
-                LayoutTransaction.DoLayout(owner.DropDown, owner.DropDown, PropertyNames.Items);
-            }
-            return owner.DropDown.AccessibilityObject.GetChildCount();
-        }
-
-        internal int GetChildFragmentIndex(ToolStripItem.ToolStripItemAccessibleObject child)
-        {
-            if ((owner is null) || (owner.DropDownItems is null))
-            {
-                return -1;
-            }
-
-            for (int i = 0; i < owner.DropDownItems.Count; i++)
-            {
-                if (owner.DropDownItems[i].Available && child.Owner == owner.DropDownItems[i])
-                {
-                    return i;
-                }
-            }
-
-            return -1;
-        }
-
-        /// <summary>
-        ///  Gets the number of children belonging to an accessible object.
-        /// </summary>
-        /// <returns>The number of children.</returns>
-        internal int GetChildFragmentCount()
-        {
-            if ((owner is null) || (owner.DropDownItems is null))
-            {
-                return -1;
-            }
-
-            int count = 0;
-            for (int i = 0; i < owner.DropDownItems.Count; i++)
-            {
-                if (owner.DropDownItems[i].Available)
-                {
-                    count++;
-                }
-            }
-
-            return count;
-        }
-
-        internal AccessibleObject GetChildFragment(int index)
-        {
-            if (owner.DropDown.AccessibilityObject is ToolStrip.ToolStripAccessibleObject toolStripAccessibleObject)
-            {
-                return toolStripAccessibleObject.GetChildFragment(index);
-            }
-
-            return null;
-        }
-
-        internal override UiaCore.IRawElementProviderFragment FragmentNavigate(UiaCore.NavigateDirection direction)
-        {
-            if (owner is null || owner.DropDown is null)
-            {
-                return null;
-            }
-
-            switch (direction)
-            {
-                case UiaCore.NavigateDirection.NextSibling:
-                case UiaCore.NavigateDirection.PreviousSibling:
-                    if (!(owner.Owner is ToolStripDropDown dropDown))
-                    {
-                        break;
-                    }
-                    int index = dropDown.Items.IndexOf(owner);
-
-                    if (index == -1)
-                    {
-                        Debug.Fail("No item matched the index?");
-                        return null;
-                    }
-
-                    index += direction == UiaCore.NavigateDirection.NextSibling ? 1 : -1;
-
-                    if (index >= 0 && index < dropDown.Items.Count)
-                    {
-                        ToolStripItem item = dropDown.Items[index];
-                        if (item is ToolStripControlHost controlHostItem)
-                        {
-                            return controlHostItem.ControlAccessibilityObject;
-                        }
-
-                        return item.AccessibilityObject;
-                    }
-
-                    return null;
-            }
-
-            return base.FragmentNavigate(direction);
-        }
-    }
 }