add ControlsType.AlwaysOn for controls that should always be visible

site/Site/Pages/Documentation/Controls/Overview.razor

@@ -40,6 +40,7 @@
 // Initialize
 var node1Controls = Diagram.Controls.AddFor(Node1); // OnSelection default
 var node2Controls = Diagram.Controls.AddFor(Node2, ControlsType.OnHover);
+var node3Controls = Diagram.Controls.AddFor(Node2, ControlsType.AlwaysOn);  // Control always visible
 
 // Add
 node1Controls.Add(new SomeControl());

src/Blazor.Diagrams.Core/Controls/ControlsContainer.cs

@@ -16,6 +16,10 @@ public ControlsContainer(Model model, ControlsType type = ControlsType.OnSelecti
     {
         Model = model;
         Type = type;
+        if (type == ControlsType.AlwaysOn)
+        {
+            Visible = true;
+        }
     }
 
     public Model Model { get; }

src/Blazor.Diagrams.Core/Controls/ControlsType.cs

@@ -3,5 +3,6 @@ namespace Blazor.Diagrams.Core.Controls;
 public enum ControlsType
 {
     OnHover,
-    OnSelection
+    OnSelection,
+    AlwaysOn
 }

tests/Blazor.Diagrams.Core.Tests/Controls/ControlsContainerTests.cs

@@ -0,0 +1,28 @@
+using Blazor.Diagrams.Core.Controls;
+using Blazor.Diagrams.Core.Events;
+using Blazor.Diagrams.Core.Models;
+using Xunit;
+
+namespace Blazor.Diagrams.Core.Tests.Controls
+{
+    public class ControlsContainerTests
+    {
+        [Fact]
+        public void AlwaysOnControlType_AlwaysVisible()
+        {
+            // Arrange
+            var diagram = new TestDiagram();
+            var node = diagram.Nodes.Add(new NodeModel());
+            var controls = diagram.Controls.AddFor(node, ControlsType.AlwaysOn);
+
+            // Assert
+            Assert.True(controls.Visible);
+
+            node.Selected = true;
+            Assert.True(controls.Visible);
+
+            diagram.TriggerPointerEnter(node, new PointerEventArgs(0, 0, 0, 0, false, false, false, 0, 0, 0, 0, 0, 0, string.Empty, true));
+            Assert.True(controls.Visible);
+        }
+    }
+}