Add initial SplitContainer component

BlinForms.Framework/BlontrolAdapter.cs

@@ -36,7 +36,7 @@ namespace BlinForms.Framework
 
         public override string ToString()
         {
-            return $"Blontrol: Name={Name ?? "<?>"}, Target={TargetControl?.GetType().Name ?? "<?>"}, #Children={Children.Count}";
+            return $"Bladapter: Name={Name ?? "<?>"}, Target={TargetControl?.GetType().Name ?? "<?>"}, #Children={Children.Count}";
         }
 
         internal void ApplyEdits(int componentId, ArrayBuilderSegment<RenderTreeEdit> edits, ArrayRange<RenderTreeFrame> referenceFrames, RenderBatch batch)
@@ -134,10 +134,23 @@ namespace BlinForms.Framework
 
             TargetControl = nativeControl;
 
-            // Add the new native control to the parent's child controls (the parent adapter is our
-            // container, so the parent adapter's control is our control's container.
-            AddChildControl(siblingIndex, TargetControl);
-
+            if (nativeControl is ICustomParentingBehavior customChildBehavior)
+            {
+                customChildBehavior.SetActualParentControl(Parent.TargetControl);
+            }
+            else
+            {
+                if (Parent.TargetControl is ICustomParentingBehavior customParentBehavior)
+                {
+                    AddChildControl(customParentBehavior.GetEffectiveParentControl(), siblingIndex, TargetControl);
+                }
+                else
+                {
+                    // Add the new native control to the parent's child controls (the parent adapter is our
+                    // container, so the parent adapter's control is our control's container.
+                    AddChildControl(Parent.TargetControl, siblingIndex, TargetControl);
+                }
+            }
 
             var endIndexExcl = frameIndex + frames[frameIndex].ElementSubtreeLength;
             for (var descendantIndex = frameIndex + 1; descendantIndex < endIndexExcl; descendantIndex++)
@@ -215,19 +228,19 @@ namespace BlinForms.Framework
             }
         }
 
-        private void AddChildControl(int siblingIndex, Control childControl)
+        private static void AddChildControl(Control parentControl, int siblingIndex, Control childControl)
         {
-            if (siblingIndex <= Parent.TargetControl.Controls.Count)
+            if (siblingIndex <= parentControl.Controls.Count)
             {
                 // WinForms ControlCollection doesn't support Insert(), so add the new child at the end,
                 // and then re-order the collection to move the control to the correct index.
-                Parent.TargetControl.Controls.Add(childControl);
-                Parent.TargetControl.Controls.SetChildIndex(childControl, siblingIndex);
+                parentControl.Controls.Add(childControl);
+                parentControl.Controls.SetChildIndex(childControl, siblingIndex);
             }
             else
             {
-                Debug.WriteLine($"WARNING: {nameof(AddChildControl)} called with {nameof(siblingIndex)}={siblingIndex}, but Parent.TargetControl.Controls.Count={Parent.TargetControl.Controls.Count}");
-                Parent.TargetControl.Controls.Add(childControl);
+                Debug.WriteLine($"WARNING: {nameof(AddChildControl)} called with {nameof(siblingIndex)}={siblingIndex}, but parentControl.Controls.Count={parentControl.Controls.Count}");
+                parentControl.Controls.Add(childControl);
             }
         }
 

BlinForms.Framework/Controls/ICustomParentingBehavior.cs

@@ -0,0 +1,15 @@
+using System.Windows.Forms;
+
+namespace BlinForms.Framework.Controls
+{
+    /// <summary>
+    /// Indicates that a control has a custom behavior for determining where child controls should be parented to.
+    /// For example, a SplitContainer control has built-in immutable children, and should not have those children
+    /// created directly.
+    /// </summary>
+    internal interface ICustomParentingBehavior
+    {
+        void SetActualParentControl(Control parentControl);
+        Control GetEffectiveParentControl();
+    }
+}

BlinForms.Framework/Controls/PlaceholderControl.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Windows.Forms;
+
+namespace BlinForms.Framework.Controls
+{
+    public class PlaceholderControl : Control, ICustomParentingBehavior
+    {
+        private Control _parentControl;
+
+        public string State { get; set; }
+
+        public Control GetEffectiveParentControl()
+        {
+            var parentSplitter = (System.Windows.Forms.SplitContainer)_parentControl;
+            var containerPanel = State == "Panel1" ? parentSplitter.Panel1 : State == "Panel2" ? parentSplitter.Panel2 : throw new InvalidOperationException("Invalid panel state!!!");
+            return containerPanel;
+        }
+
+        public void SetActualParentControl(Control parentControl)
+        {
+            _parentControl = parentControl;
+        }
+    }
+}

BlinForms.Framework/Controls/SplitContainer.cs

@@ -0,0 +1,44 @@
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.RenderTree;
+using System.Windows.Forms;
+
+namespace BlinForms.Framework.Controls
+{
+    public class SplitContainer : FormsComponentBase
+    {
+        static SplitContainer()
+        {
+            BlontrolAdapter.KnownElements.Add(typeof(SplitContainer).FullName, renderer => new BlazorSplitContainer());
+        }
+
+        [Parameter] public RenderFragment ChildContent { get; set; }
+        [Parameter] public Orientation Orientation { get; set; }
+
+        protected override void RenderAttributes(RenderTreeBuilder builder)
+        {
+            builder.AddAttribute(1, nameof(Orientation), (int)Orientation);
+        }
+
+        protected override void RenderContents(RenderTreeBuilder builder)
+        {
+            builder.AddContent(1000, ChildContent);
+        }
+
+        class BlazorSplitContainer : System.Windows.Forms.SplitContainer, IBlazorNativeControl
+        {
+            public void ApplyAttribute(ulong attributeEventHandlerId, string attributeName, object attributeValue, string attributeEventUpdatesAttributeName)
+            {
+                switch (attributeName)
+                {
+                    case nameof(Orientation):
+                        if ((attributeValue as string) != "0")
+                            Orientation = (Orientation)int.Parse((string)attributeValue);
+                        break;
+                    default:
+                        FormsComponentBase.ApplyAttribute(this, attributeEventHandlerId, attributeName, attributeValue, attributeEventUpdatesAttributeName);
+                        break;
+                }
+            }
+        }
+    }
+}

BlinForms.Framework/Controls/SplitterPanel1.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.RenderTree;
+
+namespace BlinForms.Framework.Controls
+{
+    public class SplitterPanel1 : FormsComponentBase
+    {
+        static SplitterPanel1()
+        {
+            BlontrolAdapter.KnownElements.Add(typeof(SplitterPanel1).FullName, _ => new PlaceholderControl() { State = "Panel1", });
+        }
+
+        [Parameter] public RenderFragment ChildContent { get; set; }
+
+        protected override void RenderContents(RenderTreeBuilder builder)
+        {
+            builder.AddContent(1000, ChildContent);
+        }
+    }
+}

BlinForms.Framework/Controls/SplitterPanel2.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.RenderTree;
+
+namespace BlinForms.Framework.Controls
+{
+    public class SplitterPanel2 : FormsComponentBase
+    {
+        static SplitterPanel2()
+        {
+            BlontrolAdapter.KnownElements.Add(typeof(SplitterPanel2).FullName, _ => new PlaceholderControl() { State = "Panel2", });
+        }
+
+        [Parameter] public RenderFragment ChildContent { get; set; }
+
+        protected override void RenderContents(RenderTreeBuilder builder)
+        {
+            builder.AddContent(1000, ChildContent);
+        }
+    }
+}

Sample/WinCounter.razor

@@ -1,7 +1,7 @@
 @using BlinForms.Framework.Controls
 @using System.Drawing
 
-<Panel Visible="true" BackColor="Color.Red" Top="200" Left="300" Width="300" Height="200" Anchor="@(System.Windows.Forms.AnchorStyles.Right | System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)">
+<Panel Visible="true" BackColor="Color.Red" Top="240" Left="300" Width="300" Height="200" Anchor="@(System.Windows.Forms.AnchorStyles.Right | System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)">
     <Label Top="50" Left="10" Width="150" Height="23" BackColor="Color.Yellow" Text="This label is nested"></Label>
 
     <TextBox Top="75" Left="20" Height="100" Width="150" Text="Heeeeeeey" Multiline="true" ScrollBars="System.Windows.Forms.ScrollBars.Vertical"></TextBox>
@@ -10,7 +10,7 @@
 
 @*<Timer OnTick="@OnTimerTick" />*@
 
-<Button Top="50" Width="300" Text="@("Increment: " + count)" Height="23" OnClick="@IncrementCount" />
+<Button Top="50" Width="200" Text="@("Increment: " + count)" Height="23" OnClick="@IncrementCount" />
 
 <Label Top="100" Width="200" Height="23" BackColor="Color.AliceBlue" Text="@("I'm a label: " + labelCount)"></Label>
 
@@ -26,12 +26,44 @@ else
     <Label Top="300" Width="200" Height="23" Text="Details NOT visible..."></Label>
 }
 
+<SplitContainer Top="340" Left="15" Width="250" Height="100" BackColor="Color.Salmon" Orientation="System.Windows.Forms.Orientation.Horizontal">
+    <SplitterPanel1>
+        <Button Width="100" Height="23" BackColor="Color.Aqua" Text="@("Button: " + _splitterButtonValue)" OnClick="@OnSplitterButtonClick"></Button>
+    </SplitterPanel1>
+    <SplitterPanel2>
+        <Label Width="73" Height="23" BackColor="Color.Goldenrod" Text="@("Label: " + _splitterButtonValue)"></Label>
+    </SplitterPanel2>
+</SplitContainer>
+
 @code {
     int count = 0;
     int labelCount = 0;
 
     bool isDetailsVisible = true;
 
+    int _splitterButtonValue = 0;
+
+    void OnSplitterButtonClick()
+    {
+        _splitterButtonValue++;
+    }
+
+    System.Windows.Forms.ColumnHeader[] _columns = new System.Windows.Forms.ColumnHeader[]
+    {
+        new System.Windows.Forms.ColumnHeader()
+        {
+            Text = "Tag",
+            Width = 200,
+        },
+        new System.Windows.Forms.ColumnHeader()
+        {
+            Text = "Count",
+            Width = 80,
+            TextAlign = System.Windows.Forms.HorizontalAlignment.Right,
+        },
+    };
+
+
     void IncrementCount()
     {
         count++;