Add ButtonAttribute to display methods in editor properties panel

#1917

Source/Editor/Content/Items/VisualScriptItem.cs

@@ -112,6 +112,12 @@ namespace FlaxEditor.Content
                 throw new TargetException("Missing Visual Script asset.");
             _type.Asset.SetScriptInstanceParameterValue(_parameter.Name, (Object)obj, value);
         }
+
+        /// <inheritdoc />
+        public object Invoke(object obj, object[] parameters)
+        {
+            throw new NotSupportedException();
+        }
     }
 
     sealed class VisualScriptMethodInfo : IScriptMemberInfo
@@ -240,6 +246,14 @@ namespace FlaxEditor.Content
         {
             throw new NotSupportedException();
         }
+
+        /// <inheritdoc />
+        public object Invoke(object obj, object[] parameters)
+        {
+            if (!_type.Asset)
+                throw new TargetException("Missing Visual Script asset.");
+            return _type.Asset.InvokeMethod(_index, obj, parameters);
+        }
     }
 
     /// <summary>

Source/Editor/CustomEditors/CustomEditor.cs

@@ -127,12 +127,41 @@ namespace FlaxEditor.CustomEditors
 
             _isSetBlocked = true;
             Initialize(layout);
+            ShowButtons();
             Refresh();
             _isSetBlocked = false;
 
             CurrentCustomEditor = prev;
         }
 
+        private void ShowButtons()
+        {
+            var values = Values;
+            if (values == null || values.HasDifferentTypes)
+                return;
+            var type = TypeUtils.GetObjectType(values[0]);
+            var methods = type.GetMethods(BindingFlags.Instance | BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
+            foreach (var method in methods)
+            {
+                if (!method.HasAttribute(typeof(ButtonAttribute)) ||
+                    method.ParametersCount != 0)
+                    continue;
+                var attribute = method.GetAttribute<ButtonAttribute>();
+                var text = string.IsNullOrEmpty(attribute.Text) ? Utilities.Utils.GetPropertyNameUI(method.Name) : attribute.Text;
+                var tooltip = string.IsNullOrEmpty(attribute.Tooltip) ? Editor.Instance.CodeDocs.GetTooltip(method) : attribute.Tooltip;
+                var button = _layout.Button(text, tooltip);
+                button.Button.Tag = method;
+                button.Button.ButtonClicked += OnButtonClicked;
+            }
+        }
+
+        private void OnButtonClicked(Button button)
+        {
+            var method = (ScriptMemberInfo)button.Tag;
+            var obj = method.IsStatic ? null : Values[0];
+            method.Invoke(obj);
+        }
+
         internal static CustomEditor CurrentCustomEditor;
 
         internal void OnChildCreated(CustomEditor child)

Source/Editor/Scripting/ScriptType.Interfaces.cs

@@ -293,6 +293,14 @@ namespace FlaxEditor.Scripting
         /// <param name="obj">The object whose member value will be modified.</param>
         /// <param name="value">The new member value.</param>
         void SetValue(object obj, object value);
+
+        /// <summary>
+        /// Invokes the method on a specific object (null if static) using the provided parameters.
+        /// </summary>
+        /// <param name="obj">The instance of the object to invoke its method. Use null for static methods.</param>
+        /// <param name="parameters">List of parameters to provide.</param>
+        /// <returns>The value returned by the method.</returns>
+        object Invoke(object obj, object[] parameters);
     }
 
     /// <summary>

Source/Editor/Scripting/ScriptType.cs

@@ -691,6 +691,23 @@ namespace FlaxEditor.Scripting
             else
                 _custom.SetValue(obj, value);
         }
+
+        /// <summary>
+        /// Invokes the method on a specific object (null if static) using the provided parameters.
+        /// </summary>
+        /// <param name="obj">The instance of the object to invoke its method. Use null for static methods.</param>
+        /// <param name="parameters">List of parameters to provide.</param>
+        /// <returns>The value returned by the method.</returns>
+        public object Invoke(object obj = null, object[] parameters = null)
+        {
+            if (parameters == null)
+                parameters = Array.Empty<object>();
+            if (_managed is MethodInfo methodInfo)
+                return methodInfo.Invoke(obj, parameters);
+            if (_managed != null)
+                throw new NotSupportedException();
+            return _custom.Invoke(obj, parameters);
+        }
     }
 
     /// <summary>

Source/Editor/Surface/NodeFactory.cs

@@ -39,6 +39,7 @@ namespace FlaxEditor.Surface
             typeof(TooltipAttribute),
             typeof(HideInEditorAttribute),
             typeof(NoAnimateAttribute),
+            typeof(ButtonAttribute),
         };
 
         /// <summary>

Source/Engine/Content/Assets/VisualScript.cpp

@@ -2263,6 +2263,14 @@ void VisualScript::GetMethodSignature(int32 index, String& name, byte& flags, St
     }
 }
 
+Variant VisualScript::InvokeMethod(int32 index, const Variant& instance, Span<Variant> parameters) const
+{
+    auto& method = _methods[index];
+    Variant result;
+    VisualScriptingModule.InvokeMethod((void*)&method, instance, parameters, result);
+    return result;
+}
+
 Span<byte> VisualScript::GetMetaData(int32 typeID)
 {
     auto meta = Graph.Meta.GetEntry(typeID);

Source/Engine/Content/Assets/VisualScript.h

@@ -267,6 +267,9 @@ public:
     // Gets the signature data of the method.
     API_FUNCTION() void GetMethodSignature(int32 index, API_PARAM(Out) String& name, API_PARAM(Out) byte& flags, API_PARAM(Out) String& returnTypeName, API_PARAM(Out) Array<String>& paramNames, API_PARAM(Out) Array<String>& paramTypeNames, API_PARAM(Out) Array<bool>& paramOuts);
 
+    // Invokes the method.
+    API_FUNCTION() Variant InvokeMethod(int32 index, const Variant& instance, Span<Variant> parameters) const;
+
     // Gets the metadata of the script surface.
     API_FUNCTION() Span<byte> GetMetaData(int32 typeID);
 

Source/Engine/Scripting/Attributes/Editor/ButtonAttribute.cs

@@ -0,0 +1,42 @@
+// Copyright (c) 2012-2024 Wojciech Figat. All rights reserved.
+
+using System;
+
+namespace FlaxEngine
+{
+    /// <summary>
+    /// Displays the method in the properties panel where user can click and invoke this method.
+    /// </summary>
+    /// <remarks>Supported on both static and member methods that are parameterless.</remarks>
+    [AttributeUsage(AttributeTargets.Method)]
+    public sealed class ButtonAttribute : Attribute
+    {
+        /// <summary>
+        /// The button text. Empty value will use method name (auto-formatted).
+        /// </summary>
+        public string Text;
+
+        /// <summary>
+        /// The button tooltip text. Empty value will use method documentation.
+        /// </summary>
+        public string Tooltip;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ButtonAttribute"/> class.
+        /// </summary>
+        public ButtonAttribute()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ButtonAttribute"/> class.
+        /// </summary>
+        /// <param name="text">The button text.</param>
+        /// <param name="tooltip">The button tooltip.</param>
+        public ButtonAttribute(string text, string tooltip = null)
+        {
+            Text = text;
+            Tooltip = tooltip;
+        }
+    }
+}