diff --git a/Import/GacUI.cpp b/Import/GacUI.cpp
index 4ac33bd6..b5a3fb64 100644
--- a/Import/GacUI.cpp
+++ b/Import/GacUI.cpp
@@ -4542,37 +4542,62 @@ namespace vl
 GuiBindableTextList::ItemSource
 ***********************************************************************/
 
-			GuiBindableTextList::ItemSource::ItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			GuiBindableTextList::ItemSource::ItemSource()
 			{
-				if (auto ol = _itemSource.Cast<IValueObservableList>())
-				{
-					itemSource = ol;
-					itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
-					{
-						InvokeOnItemModified(start, oldCount, newCount);
-					});
-				}
-				else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
-				{
-					itemSource = rl;
-				}
-				else
-				{
-					itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
-				}
 			}
 
 			GuiBindableTextList::ItemSource::~ItemSource()
 			{
+				SetItemSource(nullptr);
+			}
+
+			Ptr<description::IValueEnumerable> GuiBindableTextList::ItemSource::GetItemSource()
+			{
+				return itemSource;
+			}
+
+			void GuiBindableTextList::ItemSource::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			{
+				vint oldCount = 0;
+				if (itemSource)
+				{
+					oldCount = itemSource->GetCount();
+				}
 				if (itemChangedEventHandler)
 				{
 					auto ol = itemSource.Cast<IValueObservableList>();
 					ol->ItemChanged.Remove(itemChangedEventHandler);
 				}
+
+				itemSource = nullptr;
+				itemChangedEventHandler = nullptr;
+
+				if (_itemSource)
+				{
+					if (auto ol = _itemSource.Cast<IValueObservableList>())
+					{
+						itemSource = ol;
+						itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
+						{
+							InvokeOnItemModified(start, oldCount, newCount);
+						});
+					}
+					else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
+					{
+						itemSource = rl;
+					}
+					else
+					{
+						itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
+					}
+				}
+
+				InvokeOnItemModified(0, oldCount, itemSource ? itemSource->GetCount() : 0);
 			}
 
 			description::Value GuiBindableTextList::ItemSource::Get(vint index)
 			{
+				if (!itemSource) return Value();
 				return itemSource->Get(index);
 			}
 
@@ -4585,6 +4610,7 @@ GuiBindableTextList::ItemSource
 			
 			vint GuiBindableTextList::ItemSource::Count()
 			{
+				if (!itemSource) return 0;
 				return itemSource->GetCount();
 			}
 			
@@ -4616,9 +4642,12 @@ GuiBindableTextList::ItemSource
 
 			description::Value GuiBindableTextList::ItemSource::GetBindingValue(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					return itemSource->Get(itemIndex);
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						return itemSource->Get(itemIndex);
+					}
 				}
 				return Value();
 			}
@@ -4632,6 +4661,7 @@ GuiBindableTextList::ItemSource
 			
 			bool GuiBindableTextList::ItemSource::ContainsPrimaryText(vint itemIndex)
 			{
+				if (!itemSource) return false;
 				return 0 <= itemIndex && itemIndex < itemSource->GetCount();
 			}
 					
@@ -4639,21 +4669,27 @@ GuiBindableTextList::ItemSource
 
 			WString GuiBindableTextList::ItemSource::GetText(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					return ReadProperty(itemSource->Get(itemIndex), textProperty).GetText();
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						return ReadProperty(itemSource->Get(itemIndex), textProperty).GetText();
+					}
 				}
 				return L"";
 			}
 			
 			bool GuiBindableTextList::ItemSource::GetChecked(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					auto value = ReadProperty(itemSource->Get(itemIndex), checkedProperty);
-					if (value.GetTypeDescriptor() == description::GetTypeDescriptor<bool>())
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
 					{
-						return UnboxValue<bool>(value);
+						auto value = ReadProperty(itemSource->Get(itemIndex), checkedProperty);
+						if (value.GetTypeDescriptor() == description::GetTypeDescriptor<bool>())
+						{
+							return UnboxValue<bool>(value);
+						}
 					}
 				}
 				return false;
@@ -4661,10 +4697,13 @@ GuiBindableTextList::ItemSource
 			
 			void GuiBindableTextList::ItemSource::SetCheckedSilently(vint itemIndex, bool value)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					auto thisValue = itemSource->Get(itemIndex);
-					WriteProperty(thisValue, checkedProperty, BoxValue(value));
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						auto thisValue = itemSource->Get(itemIndex);
+						WriteProperty(thisValue, checkedProperty, BoxValue(value));
+					}
 				}
 			}
 
@@ -4672,8 +4711,8 @@ GuiBindableTextList::ItemSource
 GuiBindableTextList
 ***********************************************************************/
 
-			GuiBindableTextList::GuiBindableTextList(IStyleProvider* _styleProvider, list::TextItemStyleProvider::IBulletFactory* _bulletFactory, Ptr<description::IValueEnumerable> _itemSource)
-				:GuiVirtualTextList(_styleProvider, _bulletFactory, new ItemSource(_itemSource))
+			GuiBindableTextList::GuiBindableTextList(IStyleProvider* _styleProvider, list::TextItemStyleProvider::IBulletFactory* _bulletFactory)
+				:GuiVirtualTextList(_styleProvider, _bulletFactory, new ItemSource)
 			{
 				itemSource = dynamic_cast<ItemSource*>(GetItemProvider());
 
@@ -4685,6 +4724,16 @@ GuiBindableTextList
 			{
 			}
 
+			Ptr<description::IValueEnumerable> GuiBindableTextList::GetItemSource()
+			{
+				return itemSource->GetItemSource();
+			}
+
+			void GuiBindableTextList::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			{
+				itemSource->SetItemSource(_itemSource);
+			}
+
 			const WString& GuiBindableTextList::GetTextProperty()
 			{
 				return itemSource->textProperty;
@@ -4766,40 +4815,64 @@ GuiBindableListView::ListViewColumns
 GuiBindableListView::ItemSource
 ***********************************************************************/
 
-			GuiBindableListView::ItemSource::ItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			GuiBindableListView::ItemSource::ItemSource()
 			{
-				if (auto ol = _itemSource.Cast<IValueObservableList>())
-				{
-					itemSource = ol;
-					itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
-					{
-						InvokeOnItemModified(start, oldCount, newCount);
-					});
-				}
-				else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
-				{
-					itemSource = rl;
-				}
-				else
-				{
-					itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
-				}
-
 				columns.itemProvider = this;
 				dataColumns.itemProvider = this;
 			}
 
 			GuiBindableListView::ItemSource::~ItemSource()
 			{
+				SetItemSource(nullptr);
+			}
+
+			Ptr<description::IValueEnumerable> GuiBindableListView::ItemSource::GetItemSource()
+			{
+				return itemSource;
+			}
+
+			void GuiBindableListView::ItemSource::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			{
+				vint oldCount = 0;
+				if (itemSource)
+				{
+					oldCount = itemSource->GetCount();
+				}
 				if (itemChangedEventHandler)
 				{
 					auto ol = itemSource.Cast<IValueObservableList>();
 					ol->ItemChanged.Remove(itemChangedEventHandler);
 				}
+
+				itemSource = nullptr;
+				itemChangedEventHandler = nullptr;
+
+				if (_itemSource)
+				{
+					if (auto ol = _itemSource.Cast<IValueObservableList>())
+					{
+						itemSource = ol;
+						itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
+						{
+							InvokeOnItemModified(start, oldCount, newCount);
+						});
+					}
+					else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
+					{
+						itemSource = rl;
+					}
+					else
+					{
+						itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
+					}
+				}
+
+				InvokeOnItemModified(0, oldCount, itemSource ? itemSource->GetCount() : 0);
 			}
 
 			description::Value GuiBindableListView::ItemSource::Get(vint index)
 			{
+				if (!itemSource) return Value();
 				return itemSource->Get(index);
 			}
 
@@ -4810,6 +4883,7 @@ GuiBindableListView::ItemSource
 
 			bool GuiBindableListView::ItemSource::NotifyUpdate(vint start, vint count)
 			{
+				if (!itemSource) return false;
 				if (start<0 || start >= itemSource->GetCount() || count <= 0 || start + count > itemSource->GetCount())
 				{
 					return false;
@@ -4835,6 +4909,7 @@ GuiBindableListView::ItemSource
 
 			vint GuiBindableListView::ItemSource::Count()
 			{
+				if (!itemSource) return 0;
 				return itemSource->GetCount();
 			}
 
@@ -4870,9 +4945,12 @@ GuiBindableListView::ItemSource
 
 			description::Value GuiBindableListView::ItemSource::GetBindingValue(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					return itemSource->Get(itemIndex);
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						return itemSource->Get(itemIndex);
+					}
 				}
 				return Value();
 			}
@@ -4893,38 +4971,50 @@ GuiBindableListView::ItemSource
 
 			Ptr<GuiImageData> GuiBindableListView::ItemSource::GetSmallImage(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					auto value = ReadProperty(itemSource->Get(itemIndex), smallImageProperty);
-					return value.GetSharedPtr().Cast<GuiImageData>();
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						auto value = ReadProperty(itemSource->Get(itemIndex), smallImageProperty);
+						return value.GetSharedPtr().Cast<GuiImageData>();
+					}
 				}
-				return 0;
+				return nullptr;
 			}
 
 			Ptr<GuiImageData> GuiBindableListView::ItemSource::GetLargeImage(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+				if (itemSource)
 				{
-					auto value = ReadProperty(itemSource->Get(itemIndex), largeImageProperty);
-					return value.GetSharedPtr().Cast<GuiImageData>();
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount())
+					{
+						auto value = ReadProperty(itemSource->Get(itemIndex), largeImageProperty);
+						return value.GetSharedPtr().Cast<GuiImageData>();
+					}
 				}
-				return 0;
+				return nullptr;
 			}
 
 			WString GuiBindableListView::ItemSource::GetText(vint itemIndex)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount() && columns.Count()>0)
+				if (itemSource)
 				{
-					return ReadProperty(itemSource->Get(itemIndex), columns[0]->GetTextProperty()).GetText();
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount() && columns.Count()>0)
+					{
+						return ReadProperty(itemSource->Get(itemIndex), columns[0]->GetTextProperty()).GetText();
+					}
 				}
 				return L"";
 			}
 
 			WString GuiBindableListView::ItemSource::GetSubItem(vint itemIndex, vint index)
 			{
-				if (0 <= itemIndex && itemIndex < itemSource->GetCount() && 0 <= index && index < columns.Count() - 1)
+				if (itemSource)
 				{
-					return ReadProperty(itemSource->Get(itemIndex), columns[index + 1]->GetTextProperty()).GetText();
+					if (0 <= itemIndex && itemIndex < itemSource->GetCount() && 0 <= index && index < columns.Count() - 1)
+					{
+						return ReadProperty(itemSource->Get(itemIndex), columns[index + 1]->GetTextProperty()).GetText();
+					}
 				}
 				return L"";
 			}
@@ -4956,8 +5046,8 @@ GuiBindableListView::ItemSource
 
 			bool GuiBindableListView::ItemSource::DetachCallback(ListViewColumnItemArranger::IColumnItemViewCallback* value)
 			{
-				vint index=columnItemViewCallbacks.IndexOf(value);
-				if(index==-1)
+				vint index = columnItemViewCallbacks.IndexOf(value);
+				if (index == -1)
 				{
 					return false;
 				}
@@ -4975,7 +5065,7 @@ GuiBindableListView::ItemSource
 
 			WString GuiBindableListView::ItemSource::GetColumnText(vint index)
 			{
-				if(index<0 || index>=columns.Count())
+				if (index < 0 || index >= columns.Count())
 				{
 					return L"";
 				}
@@ -4987,7 +5077,7 @@ GuiBindableListView::ItemSource
 
 			vint GuiBindableListView::ItemSource::GetColumnSize(vint index)
 			{
-				if(index<0 || index>=columns.Count())
+				if (index < 0 || index >= columns.Count())
 				{
 					return 0;
 				}
@@ -4999,7 +5089,7 @@ GuiBindableListView::ItemSource
 
 			void GuiBindableListView::ItemSource::SetColumnSize(vint index, vint value)
 			{
-				if(index>=0 && index<columns.Count())
+				if (index >= 0 && index < columns.Count())
 				{
 					columns[index]->SetSize(value);
 				}
@@ -5007,7 +5097,7 @@ GuiBindableListView::ItemSource
 
 			GuiMenu* GuiBindableListView::ItemSource::GetDropdownPopup(vint index)
 			{
-				if(index<0 || index>=columns.Count())
+				if (index < 0 || index >= columns.Count())
 				{
 					return 0;
 				}
@@ -5019,7 +5109,7 @@ GuiBindableListView::ItemSource
 
 			GuiListViewColumnHeader::ColumnSortingState GuiBindableListView::ItemSource::GetSortingState(vint index)
 			{
-				if(index<0 || index>=columns.Count())
+				if (index < 0 || index >= columns.Count())
 				{
 					return GuiListViewColumnHeader::NotSorted;
 				}
@@ -5033,8 +5123,8 @@ GuiBindableListView::ItemSource
 GuiBindableListView
 ***********************************************************************/
 
-			GuiBindableListView::GuiBindableListView(IStyleProvider* _styleProvider, Ptr<description::IValueEnumerable> _itemSource)
-				:GuiVirtualListView(_styleProvider, new ItemSource(_itemSource))
+			GuiBindableListView::GuiBindableListView(IStyleProvider* _styleProvider)
+				:GuiVirtualListView(_styleProvider, new ItemSource)
 			{
 				itemSource = dynamic_cast<ItemSource*>(GetItemProvider());
 
@@ -5056,6 +5146,16 @@ GuiBindableListView
 				return itemSource->GetColumns();
 			}
 
+			Ptr<description::IValueEnumerable> GuiBindableListView::GetItemSource()
+			{
+				return itemSource->GetItemSource();
+			}
+
+			void GuiBindableListView::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			{
+				itemSource->SetItemSource(_itemSource);
+			}
+
 			const WString& GuiBindableListView::GetLargeImageProperty()
 			{
 				return itemSource->largeImageProperty;
@@ -5153,9 +5253,9 @@ GuiBindableTreeView::ItemSourceNode
 				{
 					auto ol = childrenVirtualList.Cast<IValueObservableList>();
 					ol->ItemChanged.Remove(itemChangedEventHandler);
-					itemChangedEventHandler = 0;
+					itemChangedEventHandler = nullptr;
 				}
-				childrenVirtualList = 0;
+				childrenVirtualList = nullptr;
 				FOREACH(Ptr<ItemSourceNode>, node, children)
 				{
 					node->UnprepareChildren();
@@ -5171,17 +5271,16 @@ GuiBindableTreeView::ItemSourceNode
 			{
 			}
 
-			GuiBindableTreeView::ItemSourceNode::ItemSourceNode(const description::Value& _itemSource, ItemSource* _rootProvider)
-				:itemSource(_itemSource)
-				, rootProvider(_rootProvider)
-				, parent(0)
+			GuiBindableTreeView::ItemSourceNode::ItemSourceNode(ItemSource* _rootProvider)
+				:rootProvider(_rootProvider)
+				, parent(nullptr)
 				, callback(_rootProvider)
 			{
 			}
 
 			GuiBindableTreeView::ItemSourceNode::~ItemSourceNode()
 			{
-				UnprepareChildren();
+				SetItemSource(Value());
 			}
 
 			description::Value GuiBindableTreeView::ItemSourceNode::GetItemSource()
@@ -5189,6 +5288,16 @@ GuiBindableTreeView::ItemSourceNode
 				return itemSource;
 			}
 
+			void GuiBindableTreeView::ItemSourceNode::SetItemSource(const description::Value& _itemSource)
+			{
+				vint oldCount = GetChildCount();
+				UnprepareChildren();
+				itemSource = _itemSource;
+				vint newCount = GetChildCount();
+				callback->OnBeforeItemModified(this, 0, oldCount, newCount);
+				callback->OnAfterItemModified(this, 0, oldCount, newCount);
+			}
+
 			bool GuiBindableTreeView::ItemSourceNode::GetExpanding()
 			{
 				return this == rootProvider->rootNode.Obj() ? true : expanding;
@@ -5259,15 +5368,25 @@ GuiBindableTreeView::ItemSourceNode
 GuiBindableTreeView::ItemSource
 ***********************************************************************/
 
-			GuiBindableTreeView::ItemSource::ItemSource(const description::Value& _itemSource)
+			GuiBindableTreeView::ItemSource::ItemSource()
 			{
-				rootNode = new ItemSourceNode(_itemSource, this);
+				rootNode = new ItemSourceNode(this);
 			}
 
 			GuiBindableTreeView::ItemSource::~ItemSource()
 			{
 			}
 
+			description::Value GuiBindableTreeView::ItemSource::GetItemSource()
+			{
+				return rootNode->GetItemSource();
+			}
+
+			void GuiBindableTreeView::ItemSource::SetItemSource(const description::Value& _itemSource)
+			{
+				rootNode->SetItemSource(_itemSource);
+			}
+
 			void GuiBindableTreeView::ItemSource::UpdateBindingProperties(bool updateChildrenProperty)
 			{
 				vint oldCount = rootNode->GetChildCount();
@@ -5338,7 +5457,7 @@ GuiBindableTreeView::ItemSource
 					auto value = ReadProperty(itemSourceNode->GetItemSource(), imageProperty);
 					return value.GetSharedPtr().Cast<GuiImageData>();
 				}
-				return 0;
+				return nullptr;
 			}
 
 			WString GuiBindableTreeView::ItemSource::GetNodeText(tree::INodeProvider* node)
@@ -5354,8 +5473,8 @@ GuiBindableTreeView::ItemSource
 GuiBindableTreeView
 ***********************************************************************/
 
-			GuiBindableTreeView::GuiBindableTreeView(IStyleProvider* _styleProvider, const description::Value& _itemSource)
-				:GuiVirtualTreeView(_styleProvider, new ItemSource(_itemSource))
+			GuiBindableTreeView::GuiBindableTreeView(IStyleProvider* _styleProvider)
+				:GuiVirtualTreeView(_styleProvider, new ItemSource)
 			{
 				itemSource = dynamic_cast<ItemSource*>(GetNodeRootProvider());
 
@@ -5368,6 +5487,16 @@ GuiBindableTreeView
 			{
 			}
 
+			description::Value GuiBindableTreeView::GetItemSource()
+			{
+				throw 0;
+			}
+
+			void GuiBindableTreeView::SetItemSource(description::Value _itemSource)
+			{
+				throw 0;
+			}
+
 			const WString& GuiBindableTreeView::GetTextProperty()
 			{
 				return itemSource->textProperty;
@@ -5436,12 +5565,8 @@ GuiBindableTreeView
 GuiBindableDataColumn
 ***********************************************************************/
 
-				void BindableDataColumn::SetItemSource(Ptr<description::IValueReadonlyList> _itemSource)
-				{
-					itemSource = _itemSource;
-				}
-
 				BindableDataColumn::BindableDataColumn()
+					:dataProvider(nullptr)
 				{
 				}
 
@@ -5468,19 +5593,25 @@ GuiBindableDataColumn
 
 				description::Value BindableDataColumn::GetCellValue(vint row)
 				{
-					if (0 <= row && row < itemSource->GetCount())
+					if (dataProvider->itemSource)
 					{
-						return ReadProperty(itemSource->Get(row), valueProperty);
+						if (0 <= row && row < dataProvider->itemSource->GetCount())
+						{
+							return ReadProperty(dataProvider->itemSource->Get(row), valueProperty);
+						}
 					}
 					return Value();
 				}
 
 				void BindableDataColumn::SetCellValue(vint row, description::Value value)
 				{
-					if (0 <= row && row < itemSource->GetCount())
+					if (dataProvider->itemSource)
 					{
-						auto rowValue = itemSource->Get(row);
-						return WriteProperty(rowValue, valueProperty, value);
+						if (0 <= row && row < dataProvider->itemSource->GetCount())
+						{
+							auto rowValue = dataProvider->itemSource->Get(row);
+							return WriteProperty(rowValue, valueProperty, value);
+						}
 					}
 				}
 
@@ -5505,66 +5636,90 @@ GuiBindableDataColumn
 
 				const description::Value& BindableDataColumn::GetViewModelContext()
 				{
-					return viewModelContext;
+					return dataProvider->viewModelContext;
 				}
 
 /***********************************************************************
 GuiBindableDataProvider
 ***********************************************************************/
 
-				BindableDataProvider::BindableDataProvider(Ptr<description::IValueEnumerable> _itemSource, const description::Value& _viewModelContext)
+				BindableDataProvider::BindableDataProvider(const description::Value& _viewModelContext)
 					:viewModelContext(_viewModelContext)
 				{
-					if (auto ol = _itemSource.Cast<IValueObservableList>())
-					{
-						itemSource = ol;
-						itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
-						{
-							commandExecutor->OnDataProviderItemModified(start, oldCount, newCount);
-						});
-					}
-					else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
-					{
-						itemSource = rl;
-					}
-					else
-					{
-						itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
-					}
 				}
 
 				BindableDataProvider::~BindableDataProvider()
 				{
+					SetItemSource(nullptr);
+				}
+
+				Ptr<description::IValueEnumerable> BindableDataProvider::GetItemSource()
+				{
+					return itemSource;
+				}
+
+				void BindableDataProvider::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+				{
+					vint oldCount = 0;
+					if (itemSource)
+					{
+						oldCount = itemSource->GetCount();
+					}
 					if (itemChangedEventHandler)
 					{
 						auto ol = itemSource.Cast<IValueObservableList>();
 						ol->ItemChanged.Remove(itemChangedEventHandler);
 					}
+
+					itemSource = nullptr;
+					itemChangedEventHandler = nullptr;
+
+					if (_itemSource)
+					{
+						if (auto ol = _itemSource.Cast<IValueObservableList>())
+						{
+							itemSource = ol;
+							itemChangedEventHandler = ol->ItemChanged.Add([this](vint start, vint oldCount, vint newCount)
+							{
+								commandExecutor->OnDataProviderItemModified(start, oldCount, newCount);
+							});
+						}
+						else if (auto rl = _itemSource.Cast<IValueReadonlyList>())
+						{
+							itemSource = rl;
+						}
+						else
+						{
+							itemSource = IValueList::Create(GetLazyList<Value>(_itemSource));
+						}
+					}
+
+					commandExecutor->OnDataProviderItemModified(0, oldCount, itemSource ? itemSource->GetCount() : 0);
 				}
 
 				vint BindableDataProvider::GetRowCount()
 				{
+					if (!itemSource) return 0;
 					return itemSource->GetCount();
 				}
 
 				description::Value BindableDataProvider::GetRowValue(vint row)
 				{
-					if (0 <= row && row < itemSource->GetCount())
+					if (itemSource)
 					{
-						return itemSource->Get(row);
-					}
-					else
-					{
-						return Value();
+						if (0 <= row && row < itemSource->GetCount())
+						{
+							return itemSource->Get(row);
+						}
 					}
+					return Value();
 				}
 
 				bool BindableDataProvider::InsertBindableColumn(vint index, Ptr<BindableDataColumn> column)
 				{
 					if (InsertColumnInternal(index, column, true))
 					{
-						column->viewModelContext = viewModelContext;
-						column->itemSource = itemSource;
+						column->dataProvider = this;
 						return true;
 					}
 					else
@@ -5577,8 +5732,7 @@ GuiBindableDataProvider
 				{
 					if (AddColumnInternal(column, true))
 					{
-						column->viewModelContext = viewModelContext;
-						column->itemSource = itemSource;
+						column->dataProvider = this;
 						return true;
 					}
 					else
@@ -5591,8 +5745,7 @@ GuiBindableDataProvider
 				{
 					if (RemoveColumnInternal(column, true))
 					{
-						column->viewModelContext = Value();
-						column->itemSource = nullptr;
+						column->dataProvider = nullptr;
 						return true;
 					}
 					else
@@ -5605,8 +5758,7 @@ GuiBindableDataProvider
 				{
 					FOREACH(Ptr<StructuredColummProviderBase>, column, columns)
 					{
-						column.Cast<BindableDataColumn>()->viewModelContext = Value();
-						column.Cast<BindableDataColumn>()->itemSource = nullptr;
+						column.Cast<BindableDataColumn>()->dataProvider = nullptr;
 					}
 					return ClearColumnsInternal(true);
 				}
@@ -5633,8 +5785,8 @@ GuiBindableDataProvider
 GuiBindableDataGrid
 ***********************************************************************/
 
-			GuiBindableDataGrid::GuiBindableDataGrid(IStyleProvider* _styleProvider, Ptr<description::IValueEnumerable> _itemSource, const description::Value& _viewModelContext)
-				:GuiVirtualDataGrid(_styleProvider, new BindableDataProvider(_itemSource, _viewModelContext))
+			GuiBindableDataGrid::GuiBindableDataGrid(IStyleProvider* _styleProvider, const description::Value& _viewModelContext)
+				:GuiVirtualDataGrid(_styleProvider, new BindableDataProvider(_viewModelContext))
 			{
 				bindableDataProvider = GetStructuredDataProvider()->GetStructuredDataProvider().Cast<BindableDataProvider>();
 			}
@@ -5643,6 +5795,16 @@ GuiBindableDataGrid
 			{
 			}
 
+			Ptr<description::IValueEnumerable> GuiBindableDataGrid::GetItemSource()
+			{
+				return bindableDataProvider->GetItemSource();
+			}
+
+			void GuiBindableDataGrid::SetItemSource(Ptr<description::IValueEnumerable> _itemSource)
+			{
+				bindableDataProvider->SetItemSource(_itemSource);
+			}
+
 			bool GuiBindableDataGrid::InsertBindableColumn(vint index, Ptr<list::BindableDataColumn> column)
 			{
 				return bindableDataProvider->InsertBindableColumn(index, column);
diff --git a/Import/GacUI.h b/Import/GacUI.h
index 42665dd4..47e0a42e 100644
--- a/Import/GacUI.h
+++ b/Import/GacUI.h
@@ -16664,9 +16664,12 @@ GuiBindableTextList
 					WString											checkedProperty;
 
 				public:
-					ItemSource(Ptr<description::IValueEnumerable> _itemSource);
+					ItemSource();
 					~ItemSource();
 
+					Ptr<description::IValueEnumerable>				GetItemSource();
+					void											SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
+
 					description::Value								Get(vint index);
 					void											UpdateBindingProperties();
 					
@@ -16700,13 +16703,20 @@ GuiBindableTextList
 				/// <param name="_styleProvider">The style provider for this control.</param>
 				/// <param name="_itemStyleProvider">The item style provider callback for this control.</param>
 				/// <param name="_itemSource">The item source.</param>
-				GuiBindableTextList(IStyleProvider* _styleProvider, list::TextItemStyleProvider::IBulletFactory* _bulletFactory, Ptr<description::IValueEnumerable> _itemSource);
+				GuiBindableTextList(IStyleProvider* _styleProvider, list::TextItemStyleProvider::IBulletFactory* _bulletFactory);
 				~GuiBindableTextList();
 				
 				/// <summary>Text property name changed event.</summary>
 				compositions::GuiNotifyEvent						TextPropertyChanged;
 				/// <summary>Checked property name changed event.</summary>
 				compositions::GuiNotifyEvent						CheckedPropertyChanged;
+
+				/// <summary>Get the item source.</summary>
+				/// <returns>The item source.</returns>
+				Ptr<description::IValueEnumerable>					GetItemSource();
+				/// <summary>Set the item source.</summary>
+				/// <param name="itemSource">The item source. Null is acceptable if you want to clear all data.</param>
+				void												SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
 				
 				/// <summary>Get the text property name to get the item text from an item.</summary>
 				/// <returns>The text property name.</returns>
@@ -16787,8 +16797,11 @@ GuiBindableListView
 					WString											smallImageProperty;
 
 				public:
-					ItemSource(Ptr<description::IValueEnumerable> _itemSource);
+					ItemSource();
 					~ItemSource();
+
+					Ptr<description::IValueEnumerable>				GetItemSource();
+					void											SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
 					
 					description::Value								Get(vint index);
 					void											UpdateBindingProperties();
@@ -16839,7 +16852,7 @@ GuiBindableListView
 				/// <summary>Create a bindable List view control.</summary>
 				/// <param name="_styleProvider">The style provider for this control.</param>
 				/// <param name="_itemSource">The item source.</param>
-				GuiBindableListView(IStyleProvider* _styleProvider, Ptr<description::IValueEnumerable> _itemSource);
+				GuiBindableListView(IStyleProvider* _styleProvider);
 				~GuiBindableListView();
 
 				/// <summary>Get all data columns indices in columns.</summary>
@@ -16848,6 +16861,13 @@ GuiBindableListView
 				/// <summary>Get all columns.</summary>
 				/// <returns>All columns.</returns>
 				ListViewColumns&									GetColumns();
+
+				/// <summary>Get the item source.</summary>
+				/// <returns>The item source.</returns>
+				Ptr<description::IValueEnumerable>					GetItemSource();
+				/// <summary>Set the item source.</summary>
+				/// <param name="itemSource">The item source. Null is acceptable if you want to clear all data.</param>
+				void												SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
 				
 				/// <summary>Large image property name changed event.</summary>
 				compositions::GuiNotifyEvent						LargeImagePropertyChanged;
@@ -16904,10 +16924,11 @@ GuiBindableTreeView
 					void											UnprepareChildren();
 				public:
 					ItemSourceNode(const description::Value& _itemSource, ItemSourceNode* _parent);
-					ItemSourceNode(const description::Value& _itemSource, ItemSource* _rootProvider);
+					ItemSourceNode(ItemSource* _rootProvider);
 					~ItemSourceNode();
 
 					description::Value								GetItemSource();
+					void											SetItemSource(const description::Value& _itemSource);
 
 					// ===================== tree::INodeProvider =====================
 
@@ -16935,9 +16956,12 @@ GuiBindableTreeView
 					Ptr<ItemSourceNode>								rootNode;
 
 				public:
-					ItemSource(const description::Value& _itemSource);
+					ItemSource();
 					~ItemSource();
 
+					description::Value								GetItemSource();
+					void											SetItemSource(const description::Value& _itemSource);
+
 					void											UpdateBindingProperties(bool updateChildrenProperty);
 
 					// ===================== tree::INodeRootProvider =====================
@@ -16967,7 +16991,7 @@ GuiBindableTreeView
 				/// <summary>Create a bindable Tree view control.</summary>
 				/// <param name="_styleProvider">The style provider for this control.</param>
 				/// <param name="_itemSource">The item source.</param>
-				GuiBindableTreeView(IStyleProvider* _styleProvider, const description::Value& _itemSource);
+				GuiBindableTreeView(IStyleProvider* _styleProvider);
 				~GuiBindableTreeView();
 				
 				/// <summary>Text property name changed event.</summary>
@@ -16976,6 +17000,13 @@ GuiBindableTreeView
 				compositions::GuiNotifyEvent						ImagePropertyChanged;
 				/// <summary>Children property name changed event.</summary>
 				compositions::GuiNotifyEvent						ChildrenPropertyChanged;
+
+				/// <summary>Get the item source.</summary>
+				/// <returns>The item source.</returns>
+				description::Value									GetItemSource();
+				/// <summary>Set the item source.</summary>
+				/// <param name="itemSource">The item source. Null is acceptable if you want to clear all data.</param>
+				void												SetItemSource(description::Value _itemSource);
 				
 				/// <summary>Get the text property name to get the item text from an item.</summary>
 				/// <returns>The text property name.</returns>
@@ -17009,16 +17040,16 @@ GuiBindableDataGrid
 			
 			namespace list
 			{
+				class BindableDataProvider;
+
 				/// <summary>Column object for [T:vl.presentation.controls.GuiBindableDataGrid].</summary>
 				class BindableDataColumn : public StructuredColummProviderBase, public Description<BindableDataColumn>
 				{
 					friend class BindableDataProvider;
 				protected:
-					description::Value								viewModelContext;
-					Ptr<description::IValueReadonlyList>			itemSource;
+					BindableDataProvider*							dataProvider;
 					WString											valueProperty;
 
-					void											SetItemSource(Ptr<description::IValueReadonlyList> _itemSource);
 				public:
 					BindableDataColumn();
 					~BindableDataColumn();
@@ -17053,15 +17084,19 @@ GuiBindableDataGrid
 				/// <summary>Data provider object for [T:vl.presentation.controls.GuiBindableDataGrid].</summary>
 				class BindableDataProvider : public StructuredDataProviderBase, public Description<BindableDataProvider>
 				{
+					friend class BindableDataColumn;
 				protected:
 					description::Value								viewModelContext;
 					Ptr<description::IValueReadonlyList>			itemSource;
 					Ptr<EventHandler>								itemChangedEventHandler;
 
 				public:
-					BindableDataProvider(Ptr<description::IValueEnumerable> _itemSource, const description::Value& _viewModelContext);
+					BindableDataProvider(const description::Value& _viewModelContext);
 					~BindableDataProvider();
 
+					Ptr<description::IValueEnumerable>				GetItemSource();
+					void											SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
+
 					vint											GetRowCount()override;
 					description::Value								GetRowValue(vint row);
 
@@ -17085,8 +17120,15 @@ GuiBindableDataGrid
 				/// <param name="_styleProvider">The style provider for this control.</param>
 				/// <param name="_itemSource">The item source.</param>
 				/// <param name="_viewModelContext">The view mode context, which will be passed to every visualizers and editors in this grid.</param>
-				GuiBindableDataGrid(IStyleProvider* _styleProvider, Ptr<description::IValueEnumerable> _itemSource, const description::Value& _viewModelContext = description::Value());
+				GuiBindableDataGrid(IStyleProvider* _styleProvider, const description::Value& _viewModelContext = description::Value());
 				~GuiBindableDataGrid();
+
+				/// <summary>Get the item source.</summary>
+				/// <returns>The item source.</returns>
+				Ptr<description::IValueEnumerable>					GetItemSource();
+				/// <summary>Set the item source.</summary>
+				/// <param name="itemSource">The item source. Null is acceptable if you want to clear all data.</param>
+				void												SetItemSource(Ptr<description::IValueEnumerable> _itemSource);
 				
 				/// <summary>Insert a column.</summary>
 				/// <returns>Returns true if this operation succeeded.</returns>
diff --git a/Import/GacUICompiler.cpp b/Import/GacUICompiler.cpp
index 1e0ded9a..73bb2023 100644
--- a/Import/GacUICompiler.cpp
+++ b/Import/GacUICompiler.cpp
@@ -4111,52 +4111,9 @@ GuiListViewInstanceLoader
 			{
 			};
 
-#define BASE_TYPE GuiListViewInstanceLoaderBase<GuiBindableListView>
-			class GuiBindableListViewInstanceLoader : public BASE_TYPE
+			class GuiBindableListViewInstanceLoader : public GuiListViewInstanceLoaderBase<GuiBindableListView>
 			{
-			protected:
-				GlobalStringKey		_ItemSource;
-
-				void AddAdditionalArguments(const TypeInfo& typeInfo, GlobalStringKey variableName, ArgumentMap& arguments, collections::List<WString>& errors, Ptr<WfNewClassExpression> createControl)override
-				{
-					vint indexItemSource = arguments.Keys().IndexOf(_ItemSource);
-					if (indexItemSource != -1)
-					{
-						createControl->arguments.Add(arguments.GetByIndex(indexItemSource)[0].expression);
-					}
-				}
-			public:
-				GuiBindableListViewInstanceLoader()
-				{
-					_ItemSource = GlobalStringKey::Get(L"ItemSource");
-				}
-
-				void GetConstructorParameters(const TypeInfo& typeInfo, collections::List<GlobalStringKey>& propertyNames)override
-				{
-					if (typeInfo.typeName == GetTypeName())
-					{
-						propertyNames.Add(_ItemSource);
-					}
-					BASE_TYPE::GetConstructorParameters(typeInfo, propertyNames);
-				}
-
-				Ptr<GuiInstancePropertyInfo> GetPropertyType(const PropertyInfo& propertyInfo)override
-				{
-					if (propertyInfo.propertyName == _ItemSource)
-					{
-						if (bindable)
-						{
-							auto info = GuiInstancePropertyInfo::Assign(description::GetTypeDescriptor<IValueEnumerable>());
-							info->scope = GuiInstancePropertyInfo::Constructor;
-							info->required = true;
-							info->bindable = true;
-							return info;
-						}
-					}
-					return BASE_TYPE::GetPropertyType(propertyInfo);
-				}
 			};
-#undef BASE_TYPE
 
 /***********************************************************************
 GuiTreeViewInstanceLoader
@@ -4297,49 +4254,9 @@ GuiTreeViewInstanceLoader
 			{
 			};
 
-#define BASE_TYPE GuiTreeViewInstanceLoaderBase<GuiBindableTreeView>
-			class GuiBindableTreeViewInstanceLoader : public BASE_TYPE
+			class GuiBindableTreeViewInstanceLoader : public GuiTreeViewInstanceLoaderBase<GuiBindableTreeView>
 			{
-			protected:
-				GlobalStringKey		_ItemSource;
-
-				void AddAdditionalArguments(const TypeInfo& typeInfo, GlobalStringKey variableName, ArgumentMap& arguments, collections::List<WString>& errors, Ptr<WfNewClassExpression> createControl)override
-				{
-					vint indexItemSource = arguments.Keys().IndexOf(_ItemSource);
-					if (indexItemSource != -1)
-					{
-						createControl->arguments.Add(arguments.GetByIndex(indexItemSource)[0].expression);
-					}
-				}
-			public:
-				GuiBindableTreeViewInstanceLoader()
-				{
-					_ItemSource = GlobalStringKey::Get(L"ItemSource");
-				}
-
-				void GetConstructorParameters(const TypeInfo& typeInfo, collections::List<GlobalStringKey>& propertyNames)override
-				{
-					if (typeInfo.typeName == GetTypeName())
-					{
-						propertyNames.Add(_ItemSource);
-					}
-					BASE_TYPE::GetConstructorParameters(typeInfo, propertyNames);
-				}
-
-				Ptr<GuiInstancePropertyInfo> GetPropertyType(const PropertyInfo& propertyInfo)override
-				{
-					if (propertyInfo.propertyName == _ItemSource)
-					{
-						auto info = GuiInstancePropertyInfo::Assign(description::GetTypeDescriptor<Value>());
-						info->scope = GuiInstancePropertyInfo::Constructor;
-						info->required = true;
-						info->bindable = true;
-						return info;
-					}
-					return BASE_TYPE::GetPropertyType(propertyInfo);
-				}
 			};
-#undef BASE_TYPE
 
 /***********************************************************************
 GuiBindableTextListInstanceLoader
@@ -4348,53 +4265,16 @@ GuiBindableTextListInstanceLoader
 #define BASE_TYPE GuiTemplateControlInstanceLoader<GuiBindableTextList, GuiTextListTemplate_StyleProvider, GuiTextListTemplate>
 			class GuiBindableTextListInstanceLoader : public BASE_TYPE
 			{
-			protected:
-				GlobalStringKey					_ItemSource;
-				
-				void AddAdditionalArguments(const TypeInfo& typeInfo, GlobalStringKey variableName, ArgumentMap& arguments, collections::List<WString>& errors, Ptr<WfNewClassExpression> createControl)override
-				{
-					vint indexItemSource = arguments.Keys().IndexOf(_ItemSource);
-					if (indexItemSource != -1)
-					{
-						createControl->arguments.Add(arguments.GetByIndex(indexItemSource)[0].expression);
-					}
-				}
 			public:
-				GuiBindableTextListInstanceLoader(const WString& type)
-					:BASE_TYPE(
-						L"presentation::controls::GuiBindable" + type + L"TextList",
-						L"CreateTextListStyle",
-						L"Create" + type + L"TextListItemStyle"
-						)
+				GuiBindableTextListInstanceLoader()
+					:BASE_TYPE(description::TypeInfo<GuiBindableTextList>::TypeName, L"CreateTextListStyle", L"CreateTextListItemStyle")
 				{
-					_ItemSource = GlobalStringKey::Get(L"ItemSource");
 				}
 
 				GlobalStringKey GetTypeName()override
 				{
 					return typeName;
 				}
-				void GetConstructorParameters(const TypeInfo& typeInfo, collections::List<GlobalStringKey>& propertyNames)override
-				{
-					if (typeInfo.typeName == GetTypeName())
-					{
-						propertyNames.Add(_ItemSource);
-					}
-					BASE_TYPE::GetConstructorParameters(typeInfo, propertyNames);
-				}
-
-				Ptr<GuiInstancePropertyInfo> GetPropertyType(const PropertyInfo& propertyInfo)override
-				{
-					if (propertyInfo.propertyName == _ItemSource)
-					{
-						auto info = GuiInstancePropertyInfo::Assign(description::GetTypeDescriptor<IValueEnumerable>());
-						info->scope = GuiInstancePropertyInfo::Constructor;
-						info->required = true;
-						info->bindable = true;
-						return info;
-					}
-					return BASE_TYPE::GetPropertyType(propertyInfo);
-				}
 			};
 #undef BASE_TYPE
 
@@ -4564,15 +4444,11 @@ GuiBindableDataGridInstanceLoader
 			{
 			protected:
 				GlobalStringKey		typeName;
-				GlobalStringKey		_ItemSource;
 				GlobalStringKey		_ViewModelContext;
 				GlobalStringKey		_Columns;
 				
 				void AddAdditionalArguments(const TypeInfo& typeInfo, GlobalStringKey variableName, ArgumentMap& arguments, collections::List<WString>& errors, Ptr<WfNewClassExpression> createControl)override
 				{
-					auto indexItemSource = arguments.Keys().IndexOf(_ItemSource);
-					createControl->arguments.Add(arguments.GetByIndex(indexItemSource)[0].expression);
-
 					auto indexViewModelContext = arguments.Keys().IndexOf(_ViewModelContext);
 					if (indexViewModelContext == -1)
 					{
@@ -4590,7 +4466,6 @@ GuiBindableDataGridInstanceLoader
 					:BASE_TYPE(description::TypeInfo<GuiBindableDataGrid>::TypeName, L"CreateListViewStyle")
 				{
 					typeName = GlobalStringKey::Get(description::TypeInfo<GuiBindableDataGrid>::TypeName);
-					_ItemSource = GlobalStringKey::Get(L"ItemSource");
 					_ViewModelContext = GlobalStringKey::Get(L"ViewModelContext");
 					_Columns = GlobalStringKey::Get(L"Columns");
 				}
@@ -4610,7 +4485,6 @@ GuiBindableDataGridInstanceLoader
 				{
 					if (typeInfo.typeName == GetTypeName())
 					{
-						propertyNames.Add(_ItemSource);
 						propertyNames.Add(_ViewModelContext);
 					}
 					BASE_TYPE::GetConstructorParameters(typeInfo, propertyNames);
@@ -4622,14 +4496,6 @@ GuiBindableDataGridInstanceLoader
 					{
 						return GuiInstancePropertyInfo::Collection(description::GetTypeDescriptor<list::BindableDataColumn>());
 					}
-					else if (propertyInfo.propertyName == _ItemSource)
-					{
-						auto info = GuiInstancePropertyInfo::Assign(description::GetTypeDescriptor<IValueEnumerable>());
-						info->scope = GuiInstancePropertyInfo::Constructor;
-						info->required = true;
-						info->bindable = true;
-						return info;
-					}
 					else if (propertyInfo.propertyName == _ViewModelContext)
 					{
 						auto info = GuiInstancePropertyInfo::Assign(description::GetTypeDescriptor<Value>());
@@ -4872,9 +4738,7 @@ Initialization
 				manager->SetLoader(new GuiTreeViewInstanceLoader);
 				manager->SetLoader(new GuiBindableTreeViewInstanceLoader);
 
-				manager->SetLoader(new GuiBindableTextListInstanceLoader(L""));
-				manager->SetLoader(new GuiBindableTextListInstanceLoader(L"Check"));
-				manager->SetLoader(new GuiBindableTextListInstanceLoader(L"Radio"));
+				manager->SetLoader(new GuiBindableTextListInstanceLoader);
 
 				manager->SetLoader(new GuiBindableDataColumnInstanceLoader);
 				manager->SetLoader(new GuiBindableDataGridInstanceLoader);
diff --git a/Import/GacUIReflection.cpp b/Import/GacUIReflection.cpp
index eff3d2e2..6546b29f 100644
--- a/Import/GacUIReflection.cpp
+++ b/Import/GacUIReflection.cpp
@@ -3176,8 +3176,9 @@ Type Declaration
 
 			BEGIN_CLASS_MEMBER(GuiBindableTextList)
 				CLASS_MEMBER_BASE(GuiVirtualTextList)
-				CLASS_MEMBER_CONSTRUCTOR(GuiBindableTextList*(GuiBindableTextList::IStyleProvider*, list::TextItemStyleProvider::IBulletFactory*, Ptr<IValueEnumerable>), {L"styleProvider" _ L"bulletFactory" _ L"itemSource"})
+				CLASS_MEMBER_CONSTRUCTOR(GuiBindableTextList*(GuiBindableTextList::IStyleProvider*, list::TextItemStyleProvider::IBulletFactory*), {L"styleProvider" _ L"bulletFactory"})
 
+				CLASS_MEMBER_PROPERTY_FAST(ItemSource)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(TextProperty)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(CheckedProperty)
 				CLASS_MEMBER_PROPERTY_EVENT_READONLY_FAST(SelectedItem, SelectionChanged)
@@ -3185,10 +3186,11 @@ Type Declaration
 
 			BEGIN_CLASS_MEMBER(GuiBindableListView)
 				CLASS_MEMBER_BASE(GuiVirtualListView)
-				CLASS_MEMBER_CONSTRUCTOR(GuiBindableListView*(GuiBindableListView::IStyleProvider*, Ptr<IValueEnumerable>), {L"styleProvider" _ L"itemSource"})
+				CLASS_MEMBER_CONSTRUCTOR(GuiBindableListView*(GuiBindableListView::IStyleProvider*), {L"styleProvider"})
 
 				CLASS_MEMBER_PROPERTY_READONLY_FAST(DataColumns)
 				CLASS_MEMBER_PROPERTY_READONLY_FAST(Columns)
+				CLASS_MEMBER_PROPERTY_FAST(ItemSource)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(LargeImageProperty)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(SmallImageProperty)
 				CLASS_MEMBER_PROPERTY_EVENT_READONLY_FAST(SelectedItem, SelectionChanged)
@@ -3196,8 +3198,9 @@ Type Declaration
 
 			BEGIN_CLASS_MEMBER(GuiBindableTreeView)
 				CLASS_MEMBER_BASE(GuiVirtualTreeView)
-				CLASS_MEMBER_CONSTRUCTOR(GuiBindableTreeView*(GuiBindableTreeView::IStyleProvider*, const Value&), {L"styleProvider" _ L"itemSource"})
+				CLASS_MEMBER_CONSTRUCTOR(GuiBindableTreeView*(GuiBindableTreeView::IStyleProvider*), {L"styleProvider"})
 				
+				CLASS_MEMBER_PROPERTY_FAST(ItemSource)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(TextProperty)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(ImageProperty)
 				CLASS_MEMBER_PROPERTY_GUIEVENT_FAST(ChildrenProperty)
@@ -3216,13 +3219,14 @@ Type Declaration
 
 			BEGIN_CLASS_MEMBER(GuiBindableDataGrid)
 				CLASS_MEMBER_BASE(GuiVirtualDataGrid)
-				CLASS_MEMBER_CONSTRUCTOR(GuiBindableDataGrid*(GuiBindableDataGrid::IStyleProvider*, Ptr<IValueEnumerable>, const Value&), {L"styleProvider" _ L"itemSource" _ L"viewModelContext"})
-
+				CLASS_MEMBER_CONSTRUCTOR(GuiBindableDataGrid*(GuiBindableDataGrid::IStyleProvider*, const Value&), {L"styleProvider" _ L"viewModelContext"})
+				
 				CLASS_MEMBER_METHOD(InsertBindableColumn, { L"index" _ L"column" })
 				CLASS_MEMBER_METHOD(AddBindableColumn, { L"column" })
 				CLASS_MEMBER_METHOD(RemoveBindableColumn, { L"column" })
 				CLASS_MEMBER_METHOD(ClearBindableColumns, NO_PARAMETER)
 				CLASS_MEMBER_METHOD(GetBindableColumn, { L"index" })
+				CLASS_MEMBER_PROPERTY_FAST(ItemSource)
 				CLASS_MEMBER_PROPERTY_EVENT_READONLY_FAST(SelectedRowValue, SelectedCellChanged)
 				CLASS_MEMBER_PROPERTY_EVENT_READONLY_FAST(SelectedCellValue, SelectedCellChanged)
 			END_CLASS_MEMBER(GuiBindableDataGrid)
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