Fix compile errors on trunk by introducing various compatibility extensions

com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardProvider.cs

 using System;
 using System.Collections.Generic;
 using System.Linq;
+using UnityEditor.Experimental.UIElements.GraphView;
 using UnityEditor.Graphing;
 using UnityEngine;
 using UnityEngine.Experimental.UIElements;
 
             if (create)
             {
-                field.RenameGo();
+                field.OpenTextEditor();
                 row.expanded = true;
                 m_Graph.owner.RegisterCompleteObjectUndo("Create Property");
                 m_Graph.AddShaderProperty(property);

com.unity.shadergraph/Editor/Drawing/MaterialGraphEditWindow.cs

 using Edge = UnityEditor.Experimental.UIElements.GraphView.Edge;
 #if UNITY_2018_1
 using GeometryChangedEvent = UnityEngine.Experimental.UIElements.PostLayoutEvent;
+#else
+using GeometryChangedEvent = UnityEngine.Experimental.UIElements.GeometryChangedEvent;
 #endif
 
 namespace UnityEditor.ShaderGraph.Drawing

com.unity.shadergraph/Editor/Drawing/Views/MaterialGraphView.cs

                 if (selection.OfType<MaterialNodeView>().Count() == 1 && selection.OfType<MaterialNodeView>().First().node is SubGraphNode)
                 {
                     evt.menu.AppendSeparator();
-                    evt.menu.AppendAction("Open Sub Graph", OpenSubGraph, ContextualMenu.MenuAction.AlwaysEnabled);
+                    evt.menu.AppendAction("Open Sub Graph", OpenSubGraph, ContextualMenu.MenuAction.StatusFlags.Normal);
                 }
             }
             else if (evt.target is BlackboardField)
             if (evt.target is MaterialGraphView)
             {
-                evt.menu.AppendAction("Collapse Previews", CollapsePreviews, ContextualMenu.MenuAction.AlwaysEnabled);
-                evt.menu.AppendAction("Expand Previews", ExpandPreviews, ContextualMenu.MenuAction.AlwaysEnabled);
+                evt.menu.AppendAction("Collapse Previews", CollapsePreviews, ContextualMenu.MenuAction.StatusFlags.Normal);
+                evt.menu.AppendAction("Expand Previews", ExpandPreviews, ContextualMenu.MenuAction.StatusFlags.Normal);
-        void CollapsePreviews(EventBase evt)
+        void CollapsePreviews()
         {
             graph.owner.RegisterCompleteObjectUndo("Collapse Previews");
             foreach (AbstractMaterialNode node in graph.GetNodes<AbstractMaterialNode>())
         }
 
-        void ExpandPreviews(EventBase evt)
+        void ExpandPreviews()
         {
             graph.owner.RegisterCompleteObjectUndo("Expand Previews");
             foreach (AbstractMaterialNode node in graph.GetNodes<AbstractMaterialNode>())
         }
 
-        void SeeDocumentation(EventBase evt)
+        void SeeDocumentation()
         {
             var node = selection.OfType<MaterialNodeView>().First().node;
             if (node.documentationURL != null)
-        void OpenSubGraph(EventBase evt)
+        void OpenSubGraph()
         {
             SubGraphNode subgraphNode = selection.OfType<MaterialNodeView>().First().node as SubGraphNode;
 
 
-        ContextualMenu.MenuAction.StatusFlags SeeDocumentationStatus(EventBase eventBase)
+        ContextualMenu.MenuAction.StatusFlags SeeDocumentationStatus()
         {
             if (selection.OfType<MaterialNodeView>().First().node.documentationURL == null)
                 return ContextualMenu.MenuAction.StatusFlags.Disabled;
-        ContextualMenu.MenuAction.StatusFlags ConvertToPropertyStatus(EventBase eventBase)
+        ContextualMenu.MenuAction.StatusFlags ConvertToPropertyStatus()
         {
             if (selection.OfType<MaterialNodeView>().Any(v => v.node != null))
             {
             return ContextualMenu.MenuAction.StatusFlags.Hidden;
         }
 
-        void ConvertToProperty(EventBase eventBase)
+        void ConvertToProperty()
         {
             var selectedNodeViews = selection.OfType<MaterialNodeView>().Select(x => x.node).ToList();
             foreach (var node in selectedNodeViews)
             }
         }
 
-        ContextualMenu.MenuAction.StatusFlags ConvertToInlineNodeStatus(EventBase eventBase)
+        ContextualMenu.MenuAction.StatusFlags ConvertToInlineNodeStatus()
         {
             if (selection.OfType<MaterialNodeView>().Any(v => v.node != null))
             {
             return ContextualMenu.MenuAction.StatusFlags.Hidden;
         }
 
-        void ConvertToInlineNode(EventBase eventBase)
+        void ConvertToInlineNode()
         {
             var selectedNodeViews = selection.OfType<MaterialNodeView>()
                 .Select(x => x.node)
                 ((AbstractMaterialGraph)propNode.owner).ReplacePropertyNodeWithConcreteNode(propNode);
         }
 
-        ContextualMenu.MenuAction.StatusFlags ConvertToSubgraphStatus(EventBase eventBase)
+        ContextualMenu.MenuAction.StatusFlags ConvertToSubgraphStatus()
-        void ConvertToSubgraph(EventBase eventBase)
+        void ConvertToSubgraph()
         {
             onConvertToSubgraphClick();
         }
             return selection.OfType<BlackboardField>().Any();
         }
 
+#if UNITY_2018_1
         public EventPropagation DragUpdated(IMGUIEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
         {
             return EventPropagation.Continue;
         {
             return EventPropagation.Continue;
         }
+#else
+        public bool DragUpdated(DragUpdatedEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
+        {
+            return true;
+        }
+
+        public bool DragPerform(DragPerformEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
+        {
+            return true;
+        }
+
+        bool IDropTarget.DragExited()
+        {
+            return true;
+        }
+#endif
+
     }
 
     public static class GraphViewExtensions

com.unity.shadergraph/Editor/Drawing/Views/MaterialNodeView.cs

         public override void BuildContextualMenu(ContextualMenuPopulateEvent evt)
         {
             if (evt.target is Node)
-                evt.menu.AppendAction("Copy shader", ConvertToShader, ConvertToShaderStatus);
+                evt.menu.AppendAction("Copy shader", ConvertToShader, node.hasPreview ? ContextualMenu.MenuAction.StatusFlags.Normal : ContextualMenu.MenuAction.StatusFlags.Hidden);
-        ContextualMenu.MenuAction.StatusFlags ConvertToShaderStatus(EventBase eventBase)
-        {
-            return node.hasPreview ? ContextualMenu.MenuAction.StatusFlags.Normal : ContextualMenu.MenuAction.StatusFlags.Hidden;
-        }
-
-        void ConvertToShader(EventBase eventBase)
+        void ConvertToShader()
         {
             List<PropertyCollector.TextureInfo> textureInfo;
             var masterNode = node as IMasterNode;

com.unity.shadergraph/Editor/Drawing/Views/ShaderPort.cs

 {
     sealed class ShaderPort : Port
     {
-        ShaderPort(Orientation portOrientation, Direction portDirection, Type type)
-            : base(portOrientation, portDirection, type) { AddStyleSheetPath("Styles/ShaderPort"); }
+        ShaderPort(Orientation portOrientation, Direction portDirection, Capacity portCapacity, Type type)
+            : base(portOrientation, portDirection, portCapacity, type) { AddStyleSheetPath("Styles/ShaderPort"); }
-            var port = new ShaderPort(Orientation.Horizontal, slot.isInputSlot ? Direction.Input : Direction.Output, null)
+            var port = new ShaderPort(Orientation.Horizontal, slot.isInputSlot ? Direction.Input : Direction.Output, slot.isInputSlot ? Capacity.Single : Capacity.Multi, null)
             {
                 m_EdgeConnector = new EdgeConnector<Edge>(connectorListener),
             };

com.unity.shadergraph/Editor/Util/CompatibilityExtensions.cs

+using System;
+using UnityEngine;
+using UnityEngine.Experimental.UIElements;
+
+#if UNITY_2018_1
+using UnityEditor.Experimental.UIElements.GraphView;
+#endif
+
+namespace UnityEditor.ShaderGraph.Drawing
+{
+    public static class CompatibilityExtensions
+    {
+#if UNITY_2018_1
+        public static void OpenTextEditor(this BlackboardField field)
+        {
+            field.RenameGo();
+        }
+#endif
+
+        public static void AppendAction(this ContextualMenu contextualMenu, string actionName, Action action, Func<ContextualMenu.MenuAction.StatusFlags> actionStatusCallback)
+        {
+            Debug.Assert(action != null);
+            Debug.Assert(actionStatusCallback != null);
+            contextualMenu.AppendAction(actionName, e => action(), e => actionStatusCallback());
+        }
+
+        public static void AppendAction(this ContextualMenu contextualMenu, string actionName, Action action, ContextualMenu.MenuAction.StatusFlags statusFlags)
+        {
+            Debug.Assert(action != null);
+            contextualMenu.AppendAction(actionName, e => action(), e => statusFlags);
+        }
+    }
+}

com.unity.shadergraph/Editor/Util/CompatibilityExtensions.cs.meta

+fileFormatVersion: 2
+guid: 7c1717b624ad45ccbb3fa6bec28af711
+timeCreated: 1519741123

com.unity.shadergraph/Editor/Drawing/Blackboard/Blackboard.cs.meta

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com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardField.cs.meta

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com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardRow.cs.meta

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com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardSection.cs.meta

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com.unity.shadergraph/Editor/Drawing/Blackboard/Blackboard.cs

-using System;
-using UnityEditor.Experimental.UIElements.GraphView;
-using UnityEngine;
-using UnityEngine.Experimental.UIElements;
-using UnityEngine.Experimental.UIElements.StyleEnums;
-
-namespace UnityEditor.ShaderGraph.Drawing
-{
-    class Blackboard : GraphElement
-    {
-        private const int k_DefaultWidth = 200;
-        private const float k_DefaultHeight = 400;
-        private VisualElement m_MainContainer;
-        private VisualElement m_Root;
-        private Label m_TitleLabel;
-        private Label m_SubTitleLabel;
-        private ScrollView m_ScrollView;
-        private VisualElement m_ContentContainer;
-        private VisualElement m_HeaderItem;
-        private Button m_AddButton;
-        private bool m_Scrollable = true;
-
-        public Action<Blackboard> addItemRequested { get; set; }
-        public Action<Blackboard, int, VisualElement> moveItemRequested { get; set; }
-        public Action<Blackboard, VisualElement, string> editTextRequested { get; set; }
-
-        public string title
-        {
-            get { return m_TitleLabel.text; }
-            set { m_TitleLabel.text = value; }
-        }
-
-        public string subTitle
-        {
-            get { return m_SubTitleLabel.text; }
-            set { m_SubTitleLabel.text = value; }
-        }
-
-        public override VisualElement contentContainer { get { return m_ContentContainer; } }
-
-        public bool scrollable
-        {
-            get
-            {
-                return m_Scrollable;
-            }
-            set
-            {
-                if (m_Scrollable == value)
-                    return;
-
-                m_Scrollable = value;
-
-                if (m_Scrollable)
-                {
-                    if (m_ScrollView == null)
-                    {
-                        m_ScrollView = new ScrollView();
-//                        m_ScrollView.stretchContentWidth = true;
-                    }
-
-                    // Remove the sections container from the content item and add it to the scrollview
-                    m_ContentContainer.RemoveFromHierarchy();
-                    m_Root.Add(m_ScrollView);
-                    m_ScrollView.Add(m_ContentContainer);
-                    style.positionType = PositionType.Manual; // As both the width and height can be changed by the user using a resizer
-
-                    // If the current the current geometry is invalid then set a default size
-
-                    if (layout.width == 0 || layout.height == 0)
-                    {
-                        layout = new Rect(layout.x, layout.y, layout.width == 0 ? k_DefaultWidth : layout.width, layout.height == 0 ? k_DefaultHeight : layout.height);
-                    }
-
-                    AddToClassList("scrollable");
-                }
-                else
-                {
-                    if (m_ScrollView != null)
-                    {
-                        // Remove the sections container from the scrollview and add it to the content item
-                        style.positionType = PositionType.Absolute; // As the height is automatically computed from the content but the width can be changed by the user using a resizer
-                        m_ScrollView.RemoveFromHierarchy();
-                        m_ContentContainer.RemoveFromHierarchy();
-                        m_Root.Add(m_ContentContainer);
-                    }
-                    RemoveFromClassList("scrollable");
-                }
-            }
-        }
-
-        public Blackboard()
-        {
-            AddStyleSheetPath("Styles/Blackboard");
-            var tpl = Resources.Load<VisualTreeAsset>("UXML/GraphView/Blackboard");
-
-            m_MainContainer = tpl.CloneTree(null);
-            m_MainContainer.AddToClassList("mainContainer");
-
-            m_Root = m_MainContainer.Q("content");
-
-            m_HeaderItem = m_MainContainer.Q("header");
-            m_HeaderItem.AddToClassList("blackboardHeader");
-
-            m_AddButton = m_MainContainer.Q(name: "addButton") as Button;
-            m_AddButton.clickable.clicked += () => {
-                    if (addItemRequested != null)
-                    {
-                        addItemRequested(this);
-                    }
-                };
-
-            m_TitleLabel = m_MainContainer.Q<Label>(name: "titleLabel");
-            m_SubTitleLabel = m_MainContainer.Q<Label>(name: "subTitleLabel");
-            m_ContentContainer = m_MainContainer.Q<VisualElement>(name: "contentContainer");
-
-            shadow.Add(m_MainContainer);
-
-            capabilities |= Capabilities.Movable | Capabilities.Resizable;
-            clippingOptions = ClippingOptions.ClipAndCacheContents;
-
-            ClearClassList();
-            AddToClassList("sgblackboard");
-
-//            this.AddManipulator(new Dragger { clampToParentEdges = true });
-
-            scrollable = false;
-
-//            shadow.Add(new Resizer());
-        }
-    }
-}

com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardRow.cs

-using System;
-using UnityEditor.Experimental.UIElements.GraphView;
-using UnityEngine;
-using UnityEngine.Experimental.UIElements;
-
-namespace UnityEditor.ShaderGraph.Drawing
-{
-    class BlackboardRow : GraphElement
-    {
-        private VisualElement m_Root;
-        private Button m_ExpandButton;
-        private VisualElement m_ItemContainer;
-        private VisualElement m_PropertyViewContainer;
-        private bool m_Expanded = true;
-
-        public bool expanded
-        {
-            get { return m_Expanded; }
-            set
-            {
-                if (m_Expanded == value)
-                {
-                    return;
-                }
-
-                m_Expanded = value;
-
-                if (m_Expanded)
-                {
-                    m_Root.Add(m_PropertyViewContainer);
-                    AddToClassList("expanded");
-                }
-                else
-                {
-                    m_Root.Remove(m_PropertyViewContainer);
-                    RemoveFromClassList("expanded");
-                }
-            }
-        }
-
-        public BlackboardRow(VisualElement item, VisualElement propertyView)
-        {
-            var tpl = Resources.Load<VisualTreeAsset>("UXML/GraphView/BlackboardRow");
-            VisualElement mainContainer = tpl.CloneTree(null);
-            mainContainer.AddToClassList("mainContainer");
-
-            m_Root = mainContainer.Q<VisualElement>("root");
-            m_ItemContainer = mainContainer.Q<VisualElement>("itemContainer");
-            m_PropertyViewContainer = mainContainer.Q<VisualElement>("propertyViewContainer");
-
-            m_ExpandButton = mainContainer.Q<Button>("expandButton");
-            m_ExpandButton.clickable.clicked += () => expanded = !expanded;
-
-            Add(mainContainer);
-
-            ClearClassList();
-            AddToClassList("sgblackboardRow");
-
-            m_ItemContainer.Add(item);
-            m_PropertyViewContainer.Add(propertyView);
-
-            expanded = false;
-        }
-    }
-}

com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardSection.cs

-using System;
-using System.Collections.Generic;
-using UnityEditor.Experimental.UIElements.GraphView;
-using UnityEngine;
-using UnityEngine.Experimental.UIElements;
-using UnityEngine.Experimental.UIElements.StyleEnums;
-
-namespace UnityEditor.ShaderGraph.Drawing
-{
-    class BlackboardSection : GraphElement, IDropTarget
-    {
-        private VisualElement m_DragIndicator;
-        private VisualElement m_MainContainer;
-        private VisualElement m_Header;
-        private Label m_TitleLabel;
-        private VisualElement m_RowsContainer;
-        private int m_InsertIndex;
-
-        int InsertionIndex(Vector2 pos)
-        {
-            int index = -1;
-            VisualElement owner = contentContainer != null ? contentContainer : this;
-            Vector2 localPos = this.ChangeCoordinatesTo(owner, pos);
-
-            if (owner.ContainsPoint(localPos))
-            {
-                index = 0;
-
-                foreach (VisualElement child in Children())
-                {
-                    Rect rect = child.layout;
-
-                    if (localPos.y > (rect.y + rect.height / 2))
-                    {
-                        ++index;
-                    }
-                    else
-                    {
-                        break;
-                    }
-                }
-            }
-
-            return index;
-        }
-
-        VisualElement FindSectionDirectChild(VisualElement element)
-        {
-            VisualElement directChild = element;
-
-            while ((directChild != null) && (directChild != this))
-            {
-                if (directChild.parent == this)
-                {
-                    return directChild;
-                }
-                directChild = directChild.parent;
-            }
-
-            return null;
-        }
-
-        public BlackboardSection()
-        {
-            var tpl = Resources.Load<VisualTreeAsset>("UXML/GraphView/BlackboardSection");
-            m_MainContainer = tpl.CloneTree(null);
-            m_MainContainer.AddToClassList("mainContainer");
-
-            m_Header = m_MainContainer.Q<VisualElement>("sectionHeader");
-            m_TitleLabel = m_MainContainer.Q<Label>("sectionTitleLabel");
-            m_RowsContainer = m_MainContainer.Q<VisualElement>("rowsContainer");
-
-            shadow.Add(m_MainContainer);
-
-            m_DragIndicator = new VisualElement();
-
-            m_DragIndicator.name = "dragIndicator";
-            m_DragIndicator.style.positionType = PositionType.Absolute;
-            shadow.Add(m_DragIndicator);
-
-            ClearClassList();
-            AddToClassList("sgblackboardSection");
-
-            m_InsertIndex = -1;
-        }
-
-        public override VisualElement contentContainer { get { return m_RowsContainer; } }
-
-        public string title
-        {
-            get { return m_TitleLabel.text; }
-            set { m_TitleLabel.text = value; }
-        }
-
-        public bool headerVisible
-        {
-            get { return m_Header.parent != null; }
-            set
-            {
-                if (value == (m_Header.parent != null))
-                    return;
-
-                if (value)
-                {
-                    m_MainContainer.Add(m_Header);
-                }
-                else
-                {
-                    m_MainContainer.Remove(m_Header);
-                }
-            }
-        }
-
-        private void SetDragIndicatorVisible(bool visible)
-        {
-            if (visible && (m_DragIndicator.parent == null))
-            {
-                shadow.Add(m_DragIndicator);
-                m_DragIndicator.visible = true;
-            }
-            else if ((visible == false) && (m_DragIndicator.parent != null))
-            {
-                shadow.Remove(m_DragIndicator);
-            }
-        }
-
-        public bool CanAcceptDrop(List<ISelectable> selection)
-        {
-            // Look for at least one selected element in this section to accept drop
-            foreach (ISelectable selected in selection)
-            {
-                VisualElement selectedElement = selected as VisualElement;
-
-                if (selected != null && Contains(selectedElement))
-                {
-                    return true;
-                }
-            }
-
-            return false;
-        }
-
-//        public bool DragUpdated(DragUpdatedEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
-        public EventPropagation DragUpdated(IMGUIEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
-        {
-            VisualElement sourceItem = null;
-
-            foreach (ISelectable selectedElement in selection)
-            {
-                sourceItem = selectedElement as VisualElement;
-
-                if (sourceItem == null)
-                    continue;
-            }
-
-            if (!Contains(sourceItem))
-            {
-                SetDragIndicatorVisible(false);
-
-                return EventPropagation.Continue;
-            }
-
-            var target = evt.target as VisualElement;
-//            Vector2 localPosition = target.ChangeCoordinatesTo(this, evt.localMousePosition);
-            Vector2 localPosition = target.ChangeCoordinatesTo(this, evt.imguiEvent.mousePosition);
-
-            m_InsertIndex = InsertionIndex(localPosition);
-
-            if (m_InsertIndex != -1)
-            {
-                float indicatorY = 0;
-
-                if (m_InsertIndex == childCount)
-                {
-                    VisualElement lastChild = this[childCount - 1];
-
-                    indicatorY = lastChild.ChangeCoordinatesTo(this, new Vector2(0, lastChild.layout.height + lastChild.style.marginBottom)).y;
-                }
-                else
-                {
-                    VisualElement childAtInsertIndex = this[m_InsertIndex];
-
-                    indicatorY = childAtInsertIndex.ChangeCoordinatesTo(this, new Vector2(0, -childAtInsertIndex.style.marginTop)).y;
-                }
-
-                SetDragIndicatorVisible(true);
-
-                m_DragIndicator.layout = new Rect(0, indicatorY - m_DragIndicator.layout.height / 2, layout.width, m_DragIndicator.layout.height);
-
-                return EventPropagation.Stop;
-            }
-            else
-            {
-                SetDragIndicatorVisible(false);
-
-                m_InsertIndex = -1;
-
-                return EventPropagation.Continue;
-            }
-
-        }
-
-        int IndexOf(VisualElement element)
-        {
-            var index = 0;
-            foreach (var childElement in Children())
-            {
-                if (childElement == element)
-                    return index;
-                index++;
-            }
-            return -1;
-        }
-
-        struct VisualElementPair
-        {
-            public VisualElement Item1;
-            public VisualElement Item2;
-
-            public VisualElementPair(VisualElement item1, VisualElement item2)
-            {
-                Item1 = item1;
-                Item2 = item2;
-            }
-        }
-
-//        public bool DragPerform(DragPerformEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
-        public EventPropagation DragPerform(IMGUIEvent evt, IEnumerable<ISelectable> selection, IDropTarget dropTarget)
-        {
-            if (m_InsertIndex != -1)
-            {
-                List<VisualElementPair> draggedElements = new List<VisualElementPair>();
-
-                foreach (ISelectable selectedElement in selection)
-                {
-                    var draggedElement = selectedElement as VisualElement;
-
-                    if (draggedElement != null && Contains(draggedElement))
-                    {
-                        draggedElements.Add(new VisualElementPair(FindSectionDirectChild(draggedElement), draggedElement));
-                    }
-                }
-
-                if (draggedElements.Count == 0)
-                {
-                    SetDragIndicatorVisible(false);
-
-                    return EventPropagation.Continue;
-                }
-
-                // Sorts the dragged elements from their relative order in their parent
-                draggedElements.Sort((pair1, pair2) => { return IndexOf(pair1.Item1).CompareTo(IndexOf(pair2.Item1)); });
-
-                int insertIndex = m_InsertIndex;
-
-                foreach (var draggedElement in draggedElements)
-                {
-                    VisualElement sectionDirectChild = draggedElement.Item1;
-                    int indexOfDraggedElement = IndexOf(sectionDirectChild);
-
-                    if (!((indexOfDraggedElement == insertIndex) || ((insertIndex - 1) == indexOfDraggedElement)))
-                    {
-                        Blackboard blackboard = GetFirstAncestorOfType<Blackboard>();
-
-                        if (blackboard.moveItemRequested != null)
-                        {
-                            blackboard.moveItemRequested(blackboard, m_InsertIndex, draggedElement.Item2);
-                        }
-                        else
-                        {
-                            if (insertIndex == contentContainer.childCount)
-                            {
-                                sectionDirectChild.BringToFront();
-                            }
-                            else
-                            {
-                                sectionDirectChild.PlaceBehind(this[insertIndex]);
-                            }
-                        }
-                    }
-
-                    if (insertIndex > indexOfDraggedElement) // No need to increment the insert index for the next dragged element if the current dragged element is above the current insert location.
-                        continue;
-                    insertIndex++;
-                }
-            }
-
-            SetDragIndicatorVisible(false);
-
-            return EventPropagation.Stop;
-        }
-
-        EventPropagation IDropTarget.DragExited()
-        {
-            SetDragIndicatorVisible(false);
-            return EventPropagation.Continue;
-        }
-    }
-}

com.unity.shadergraph/Editor/Drawing/Blackboard/BlackboardField.cs

-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Reflection;
-using UnityEditor.Experimental.UIElements.GraphView;
-using UnityEditor.Graphing.Util;
-using UnityEngine;
-using UnityEngine.Experimental.UIElements;
-
-namespace UnityEditor.ShaderGraph.Drawing
-{
-    class BlackboardField : GraphElement
-    {
-        private VisualElement m_ContentItem;
-        private Image m_Icon;
-        private Label m_TextLabel;
-        private TextField m_TextField;
-        private Label m_TypeLabel;
-        private bool m_EditTitleCancelled = false;
-        SelectionDropper m_SelectionDropper;
-
-        public string text
-        {
-            get { return m_TextLabel.text; }
-            set { m_TextLabel.text = value; }
-        }
-
-        public string typeText
-        {
-            get { return m_TypeLabel.text; }
-            set { m_TypeLabel.text = value; }
-        }
-
-        public Texture icon
-        {
-            get { return m_Icon.image; }
-            set
-            {
-                m_Icon.image = value;
-
-                if (value == null)
-                {
-                    AddToClassList("noIcon");
-                    m_Icon.visible = false;
-                }
-                else
-                {
-                    RemoveFromClassList("noIcon");
-                    m_Icon.visible = true;
-                }
-            }
-        }
-
-        public BlackboardField()
-            : this(null, "", "") { }
-
-        static Type s_ContextualMenuManipulator = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypesOrNothing()).FirstOrDefault(t => t.FullName == "UnityEngine.Experimental.UIElements.ContextualMenuManipulator");
-
-        public BlackboardField(Texture icon, string text, string typeText)
-        {
-            var tpl = Resources.Load<VisualTreeAsset>("UXML/GraphView/BlackboardField");
-            VisualElement mainContainer = tpl.CloneTree(null);
-
-            mainContainer.AddToClassList("mainContainer");
-            mainContainer.pickingMode = PickingMode.Ignore;
-
-            m_ContentItem = mainContainer.Q("contentItem");
-
-            m_TextLabel = mainContainer.Q<Label>("textLabel");
-            m_Icon = mainContainer.Q<Image>("iconItem");
-            m_TypeLabel = mainContainer.Q<Label>("typeLabel");
-
-            m_TextField = mainContainer.Q<TextField>("textField");
-            m_TextField.visible = false;
-            m_TextField.RegisterCallback<FocusOutEvent>(e => { OnEditTextFinished(); });
-            m_TextField.RegisterCallback<KeyDownEvent>(OnTextFieldKeyPressed);
-
-            Add(mainContainer);
-
-            RegisterCallback<MouseDownEvent>(OnMouseDownEvent);
-
-            capabilities |= Capabilities.Selectable | Capabilities.Droppable | Capabilities.Deletable;
-
-            ClearClassList();
-            AddToClassList("sgblackboardField");
-
-            this.text = text;
-            this.icon = icon;
-            this.typeText = typeText;
-
-            m_SelectionDropper = new SelectionDropper(Handler);
-            // Workaround bug causing SelectionDropper to not work (m_Active should be initialized to false rather than true)
-            var activeFieldInfo = typeof(SelectionDropper).GetFields(BindingFlags.NonPublic | BindingFlags.Instance).FirstOrDefault(f => f.Name == "m_Active");
-            Debug.Assert(activeFieldInfo != null, "activeFieldInfo != null");
-            activeFieldInfo.SetValue(m_SelectionDropper, false);
-            this.AddManipulator(m_SelectionDropper);
-
-            this.AddManipulator((IManipulator)Activator.CreateInstance(s_ContextualMenuManipulator, (Action<ContextualMenuPopulateEvent>)BuildContextualMenu));
-        }
-
-        void BuildContextualMenu(ContextualMenuPopulateEvent evt)
-        {
-            evt.menu.AppendAction("Rename", e => RenameGo(), ContextualMenu.MenuAction.AlwaysEnabled);
-        }
-
-        void Handler(IMGUIEvent evt, List<ISelectable> selection, IDropTarget dropTarget)
-        {
-            if (dropTarget == null || !dropTarget.CanAcceptDrop(selection))
-                return;
-
-            if (evt.imguiEvent.type == EventType.DragUpdated)
-                dropTarget.DragUpdated(evt, selection, dropTarget);
-            else if (evt.imguiEvent.type == EventType.DragPerform)
-                dropTarget.DragPerform(evt, selection, dropTarget);
-            else if (evt.imguiEvent.type == EventType.DragExited)
-                dropTarget.DragExited();
-
-//            if (propagation == EventPropagation.Stop)
-//                evt.StopPropagation();
-        }
-
-        private void OnTextFieldKeyPressed(KeyDownEvent e)
-        {
-            switch (e.keyCode)
-            {
-                case KeyCode.Escape:
-                    m_EditTitleCancelled = true;
-                    m_TextField.Blur();
-                    break;
-                case KeyCode.Return:
-                case KeyCode.KeypadEnter:
-                    m_TextField.Blur();
-                    break;
-                default:
-                    break;
-            }
-        }
-
-        private void OnEditTextFinished()
-        {
-            m_ContentItem.visible = true;
-            m_TextField.visible = false;
-
-            if (!m_EditTitleCancelled && (text != m_TextField.text))
-            {
-                Blackboard blackboard = GetFirstAncestorOfType<Blackboard>();
-
-                if (blackboard.editTextRequested != null)
-                {
-                    blackboard.editTextRequested(blackboard, this, m_TextField.text);
-                }
-                else
-                {
-                    text = m_TextField.text;
-                }
-            }
-
-            m_EditTitleCancelled = false;
-        }
-
-        private void OnMouseDownEvent(MouseDownEvent e)
-        {
-            if ((e.clickCount == 2) && e.button == (int)MouseButton.LeftMouse)
-            {
-                RenameGo();
-                e.PreventDefault();
-            }
-        }
-
-        internal void RenameGo()
-        {
-            m_TextField.text = text;
-            m_TextField.visible = true;
-            m_ContentItem.visible = false;
-            m_TextField.Focus();
-            m_TextField.SelectAll();
-        }
-    }
-}