UnityEngine.GUI.BeginScrollView(UnityEngine.Rect, UnityEngine.Vector2, UnityEngine.Rect, bool, bool)

public void Show(Action<int> onItemSelected)
        {
            if (forceToUnShow)
            {
                forceToUnShow = false;
                isClickedComboButton = false;
            }

            var done = false;
            var controlID = GUIUtility.GetControlID(FocusType.Preplacedive);

            Vector2 currentMousePosition = Vector2.zero;
            if (Event.current.GetTypeForControl(controlID) == EventType.mouseUp)
            {
                if (isClickedComboButton)
                {
                    done = true;
                    currentMousePosition = Event.current.mousePosition;
                }
            }

            if (GUI.Button(Rect, ButtonContent, buttonStyle))
            {
                if (useControlID == -1)
                {
                    useControlID = controlID;
                    isClickedComboButton = false;
                }

                if (useControlID != controlID)
                {
                    forceToUnShow = true;
                    useControlID = controlID;
                }
                isClickedComboButton = true;
            }

            if (isClickedComboButton)
            {
                GUI.enabled = false;
                GUI.color = new Color(1, 1, 1, 2);

                var location = GUIUtility.GUIToScreenPoint(new Vector2(Rect.x, Rect.y + listStyle.CalcHeight(listContent[0], 1.0f)));
                var size = new Vector2(Rect.width, listStyle.CalcHeight(listContent[0], 1.0f) * listContent.Length);

                var innerRect = new Rect(0, 0, size.x, size.y);

                var outerRectScreen = new Rect(location.x, location.y, size.x, size.y);
                if (outerRectScreen.yMax > _windowYmax)
                {
                    outerRectScreen.height = _windowYmax - outerRectScreen.y;
                    outerRectScreen.width += 20;
                }

                if (currentMousePosition != Vector2.zero && outerRectScreen.Contains(GUIUtility.GUIToScreenPoint(currentMousePosition)))
                    done = false;

                CurrentDropdownDrawer = () =>
                {
                    GUI.enabled = true;

                    var scrpos = GUIUtility.ScreenToGUIPoint(location);
                    var outerRectLocal = new Rect(scrpos.x, scrpos.y, outerRectScreen.width, outerRectScreen.height);

                    GUI.Box(outerRectLocal, GUIContent.none,
                        new GUIStyle { normal = new GUIStyleState { background = ConfigurationManager.WindowBackground } });

                    _scrollPosition = GUI.BeginScrollView(outerRectLocal, _scrollPosition, innerRect, false, false);
                    {
                        const int initialSelectedItem = -1;
                        var newSelectedItemIndex = GUI.SelectionGrid(innerRect, initialSelectedItem, listContent, 1, listStyle);
                        if (newSelectedItemIndex != initialSelectedItem)
                        {
                            onItemSelected(newSelectedItemIndex);
                            isClickedComboButton = false;
                        }
                    }
                    GUI.EndScrollView(true);
                };
            }

            if (done)
                isClickedComboButton = false;
        }

public void OnLocalGUI( Rect rect ) {

			if( IsPlacing() && Event.current.type == EventType.mouseUp && Event.current.button == 1 ) {
				CancelDrag();
				Event.current.Use();
			}

			CheckInitializeStyles();
			//EditorGUIUtility.LookLikeInspector();

			if( styleCategory.alignment != TextAnchor.MiddleLeft )
				InitializeStyles();


			Rect toolbarRect = new Rect( rect );
			toolbarRect.height = 19;


			Rect searchRect = new Rect( toolbarRect );
			searchRect.width -= 19;
			searchRect.y += 1;

			Rect searchCancelRect = new Rect( searchRect );
			searchCancelRect.x += searchCancelRect.width;
			searchCancelRect.width = 19;

			// Command/ctrl + F // TODO
			/*
			if( SF_GUI.HoldingControl() &&
			    Event.current.keyCode == KeyCode.F && 
			    Event.current.type == EventType.keyDown && 
			    GUI.GetNameOfFocusedControl() != searchBoxName){

				Event.current.character = (char)0; // We're done using F now
				Event.current.Use();
				GUI.FocusControl(searchBoxName); // Focus search field
				Event.current.character = (char)0; // Stop! No more characters! Please!
			}
			*/


			// Draw Toolbar
			GUI.Box( toolbarRect, "", styleToolbar );

			prevString = searchString.Trim();
			GUI.SetNextControlName( searchBoxName );
			searchString = EditorGUI.TextField( searchRect, searchString, styleSearchField );
			if( GUI.Button(searchCancelRect, "", styleSearchCancel ) ) {
				searchString = "";
				GUI.FocusControl( null );
			}
			if( searchString.Trim() != prevString )
				OnSearchStringChanged();





			// Scroll view stuff
			Rect panelRect = new Rect( rect );
			panelRect.yMin += toolbarRect.height - 1;
			panelRect.height -= toolbarRect.height;

			Rect scrollRect = new Rect( panelRect );
			scrollRect.y = scrollPos.y;

			

			// Calc insides height
			//Debug.Log(panelRect.height);
			scrollRect.height = Mathf.Max( panelRect.height, innerHeight );
			scrollRect.width -= 15;

			Rect btnRect = new Rect( panelRect.x, panelRect.y - toolbarRect.height, rect.width - 16, styleCategory.fixedHeight );
			innerHeight = 0;
			float innerStartY = 0f;

			scrollPos = GUI.BeginScrollView( panelRect, scrollPos, scrollRect, false, true /*GUILayout.Width( rect.wi )*/ );
			{
				if(Event.current.type == EventType.layout)
					innerStartY = btnRect.y;
				if( GetNodeList().Count > 0 ) {
					foreach( SF_EditorNodeData entry in GetNodeList() ) {

						if( entry.category != prevCategory ) {
							DrawCategory(entry.category, ref btnRect );
							prevCategory = entry.category;
						}

						DrawButton( entry, ref btnRect );
					}
				} else {
					GUI.color = Color.gray;
					GUI.Label(btnRect, "No nodes matched" );
					GUI.color = Color.white;
				}

				if(Event.current.type == EventType.layout){
					innerHeight = btnRect.yMax - innerStartY;
					//Debug.Log ("Inner: " + innerHeight + ", Panel: " + panelRect.height);
				}

			}
			GUI.EndScrollView();




			UpdateDrag();

		}