Now remembering the user-selected state of the TreeNode Expanded value. Fixes #68

Author: csharpfritz

samples/AfterBlazorServerSide/Shared/MainLayout.razor

@@ -6,7 +6,8 @@
 
 <div class="main">
     <div class="top-row px-4">
-        <a href="https://github.com/FritzAndFriends/BlazorWebFormsComponents" target="_blank">About BlazorWebFormsComponents</a>
+        <a target="_blank" href="https://fritzandfriends.github.io/BlazorWebFormsComponents/">BlazorWebFormsComponents Reference Documentation</a>
+        <a target="_blank" href="https://github.com/FritzAndFriends/BlazorWebFormsComponents">About BlazorWebFormsComponents</a>
     </div>
 
     <div class="content px-4">

samples/AfterBlazorServerSide/Shared/NavMenu.razor

@@ -113,4 +113,4 @@
     {
         collapseNavMenu = !collapseNavMenu;
     }
-}
+}

src/BlazorWebFormsComponents.Test/TreeView/PersistExpandedState_68.razor

@@ -0,0 +1,52 @@
+@inherits TestComponentBase
+@** Addresses issue #68 -- Remember the collapsed state across clicks *@
+
+<Fixture Test="PersistExpandedState">
+	<ComponentUnderTest>
+		<TreeView id="SampleTreeView" runat="server">
+			<Nodes>
+				<TreeNode Value="Parent"
+									Text="Parent"
+									Expanded="false">
+					<TreeNode Value="Child" Text="Child">
+						<TreeNode Value="GrandChild_1" Text="GrandChild_1" />
+						<TreeNode Value="GrandChild_2" Text="GrandChild_2" />
+					</TreeNode>
+				</TreeNode>
+			</Nodes>
+		</TreeView>
+	</ComponentUnderTest>
+
+	@code {
+
+		private TreeNode _ExpandedNode;
+
+		void PersistExpandedState(Fixture fixture)
+		{
+			var cut = fixture.GetComponentUnderTest<TreeView>();
+			var rootNode = cut.FindComponents<TreeNode>().First(n => n.Instance.Value == "Parent");
+			var childNode = cut.FindComponents<TreeNode>().First(n => n.Instance.Text == "Child");
+
+			// Expand the root node
+			rootNode.Find("a").Click();
+			rootNode.Instance.Expanded.ShouldBeTrue("Root node was not expanded");
+
+			// Collapse the child node
+			childNode.Find("a").Click();
+			childNode.Instance.Expanded.ShouldBeFalse("Child node was not collapsed");
+
+			// Collapse the root node
+			rootNode.Find("a").Click();
+			rootNode.Instance.Expanded.ShouldBeFalse("Root node was not collapsed");
+
+			// Expand the root node again
+			rootNode.Find("a").Click();
+			rootNode.Instance.Expanded.ShouldBeTrue("Root node was not expanded a second time");
+
+			// The Child node should still be collapsed
+			childNode.Instance.Expanded.ShouldBeFalse("Child node did not persist the collapsed state");
+
+		}
+	}
+
+</Fixture>

src/BlazorWebFormsComponents/TreeNode.razor.cs

@@ -20,8 +20,14 @@ public partial class TreeNode : ComponentBase
 		[Parameter]
 		public byte Depth { get; set; } = 0;
 
+		private bool _Expanded = true;
+		private bool? _UserExpanded;
 		[Parameter]
-		public bool Expanded { get; set; } = true;
+		public bool Expanded
+		{
+			get { return _UserExpanded.HasValue ? _UserExpanded.Value : _Expanded; }
+			set { _Expanded = value; }
+		}
 
 		// TODO: Implement
 		[Parameter]
@@ -179,9 +185,11 @@ protected override Task OnInitializedAsync()
 
 			Parent?.AddChildNode(this);
 
+
 			return base.OnInitializedAsync();
 		}
 
+
 		protected override void OnParametersSet() {
 
 			if (!ParentTreeView.Nodes.Contains(this))
@@ -193,7 +201,7 @@ protected override void OnParametersSet() {
 
 		public void HandleNodeExpand() {
 
-			Expanded = !Expanded;
+			_UserExpanded = !Expanded;
 
 			if (Expanded) ParentTreeView.OnTreeNodeExpanded.InvokeAsync(new TreeNodeEventArgs(this));
 			else ParentTreeView.OnTreeNodeCollapsed.InvokeAsync(new TreeNodeEventArgs(this));