Allow refreshing property grid on value changed

src/Bonsai.Gui/PropertyGridBuilder.cs

@@ -13,6 +13,7 @@ public class PropertyGridBuilder : ControlBuilderBase
     {
         internal readonly BehaviorSubject<bool> _HelpVisible = new(true);
         internal readonly BehaviorSubject<bool> _ToolbarVisible = new(true);
+        internal readonly BehaviorSubject<bool> _RefreshProperties = new(false);
 
         /// <summary>
         /// Gets or sets a value specifying whether the help text box is visible.
@@ -35,5 +36,17 @@ public bool ToolbarVisible
             get => _ToolbarVisible.Value;
             set => _ToolbarVisible.OnNext(value);
         }
+
+        /// <summary>
+        /// Gets or sets a value specifying whether the property grid should refresh
+        /// whenever the value of any property changes.
+        /// </summary>
+        [Category(nameof(CategoryAttribute.Behavior))]
+        [Description("Specifies whether the property grid should refresh whenever the value of any property changes.")]
+        public bool RefreshProperties
+        {
+            get => _RefreshProperties.Value;
+            set => _RefreshProperties.OnNext(value);
+        }
     }
 }

src/Bonsai.Gui/PropertyGridVisualizer.cs

@@ -15,18 +15,42 @@ public class PropertyGridVisualizer : ControlVisualizerBase<PropertyGrid, Proper
         /// <inheritdoc/>
         protected override PropertyGrid CreateControl(IServiceProvider provider, PropertyGridBuilder builder)
         {
+            var handlerRegistered = false;
             var propertyGrid = new PropertyGrid();
+            propertyGrid.Tag = builder;
             propertyGrid.Dock = DockStyle.Fill;
             propertyGrid.Size = new Size(350, 450);
             propertyGrid.Site = new ServiceProviderContext(provider);
             propertyGrid.SubscribeTo(builder._HelpVisible, value => propertyGrid.HelpVisible = value);
             propertyGrid.SubscribeTo(builder._ToolbarVisible, value => propertyGrid.ToolbarVisible = value);
+            propertyGrid.SubscribeTo(builder._RefreshProperties, value =>
+            {
+                if (value)
+                {
+                    propertyGrid.Refresh();
+                    if (!handlerRegistered)
+                    {
+                        propertyGrid.PropertyValueChanged += PropertyGrid_PropertyValueChanged;
+                        handlerRegistered = true;
+                    }
+                }
+            });
 
             var workflowBuilder = (WorkflowBuilder)provider.GetService(typeof(WorkflowBuilder));
             propertyGrid.SelectedObject = GetExpressionContext(workflowBuilder.Workflow, builder);
             return propertyGrid;
         }
 
+        static void PropertyGrid_PropertyValueChanged(object sender, PropertyValueChangedEventArgs e)
+        {
+            var propertyGrid = (PropertyGrid)sender;
+            var builder = (PropertyGridBuilder)propertyGrid.Tag;
+            if (builder._RefreshProperties.Value)
+            {
+                propertyGrid.Refresh();
+            }
+        }
+
         static ExpressionBuilderGraph GetExpressionContext(ExpressionBuilderGraph source, ExpressionBuilder target)
         {
             foreach (var element in source.Elements())