1. Epic GamesDeveloper
  3. STreeView

STreeView

This assumes you are familiar with [SListView](API\Runtime\Slate\SListView); see [SListView](API\Runtime\Slate\SListView).

API > API/Runtime > API/Runtime/Slate

This assumes you are familiar with SListView; see SListView.

TreeView setup is virtually identical to that of ListView. Additionally, TreeView introduces a new delegate: OnGetChildren(). OnGetChildren() takes some DataItem being observed by the tree and returns that item's children. Like ListView, TreeView operates exclusively with pointers to DataItems.

   
Name STreeView
Type class
Header File /Engine/Source/Runtime/Slate/Public/Widgets/Views/STreeView.h
Include Path #include "Widgets/Views/STreeView.h"

Syntax

template<typename ItemType>  
class STreeView : public SListView< ItemType >

Inheritance Hierarchy

Implements Interfaces

Derived Classes

STreeView derived class hierarchy

Constructors

Name Remarks Include Path Unreal Specifiers

STreeView()

 Default constructor. Widgets/Views/STreeView.h  

Structs

Name Remarks
FArguments  

Typedefs

Name Type Remarks Include Path
FIsSelectableOrNavigable typename TSlateDelegates< ItemType >::FIsSelectableOrNavigable   Widgets/Views/STreeView.h
FOnExpansionChanged typename TSlateDelegates< ItemType >::FOnExpansionChanged   Widgets/Views/STreeView.h
FOnGenerateRow typename TSlateDelegates< ItemType >::FOnGenerateRow   Widgets/Views/STreeView.h
FOnGetChildren typename TSlateDelegates< ItemType >::FOnGetChildren   Widgets/Views/STreeView.h
FOnItemScrolledIntoView typename TSlateDelegates< ItemType >::FOnItemScrolledIntoView   Widgets/Views/STreeView.h
FOnItemToString_Debug typename TSlateDelegates< ItemType >::FOnItemToString_Debug   Widgets/Views/STreeView.h
FOnMouseButtonClick typename TSlateDelegates< ItemType >::FOnMouseButtonClick   Widgets/Views/STreeView.h
FOnMouseButtonDoubleClick typename TSlateDelegates< ItemType >::FOnMouseButtonDoubleClick   Widgets/Views/STreeView.h
FOnRefreshRow typename TSlateDelegates< ItemType >::FOnRefreshRow   Widgets/Views/STreeView.h
FOnSelectionChanged typename TSlateDelegates< NullableItemType >::FOnSelectionChanged   Widgets/Views/STreeView.h
FOnSetExpansionRecursive typename TSlateDelegates< ItemType >::FOnSetExpansionRecursive   Widgets/Views/STreeView.h
FOnWidgetToBeRemoved typename SListView< ItemType >::FOnWidgetToBeRemoved   Widgets/Views/STreeView.h
MapKeyFuncs typename TListTypeTraits< ItemType >::MapKeyFuncs   Widgets/Views/STreeView.h
MapKeyFuncsSparse typename TListTypeTraits< ItemType >::MapKeyFuncsSparse   Widgets/Views/STreeView.h
NullableItemType typename TListTypeTraits< ItemType >::NullableType   Widgets/Views/STreeView.h
TItemSet TSet< TObjectPtrWrapTypeOf< ItemType >, typename TListTypeTraits< TObjectPtrWrapTypeOf< ItemType > >::SetKeyFuncs >   Widgets/Views/STreeView.h
TSparseItemMap TMap< ItemType, FSparseItemInfo, FDefaultSetAllocator, MapKeyFuncsSparse >   Widgets/Views/STreeView.h

Variables

Protected

Name Type Remarks Include Path Unreal Specifiers
bAllowInvisibleItemSelection bool True if we allow invisible items to stay selected. Widgets/Views/STreeView.h  
bHighlightParentNodesForSelection bool True if we should highlight all parents for each of the currently selected items Widgets/Views/STreeView.h  
bShouldStackHierarchyHeaders TAttribute< bool > True if we want to show the hierarchy of items pinned at the top Widgets/Views/STreeView.h  
bTreeItemsAreDirty bool True when the LinearizedItems need to be regenerated. Widgets/Views/STreeView.h  
TreeViewSource TUniquePtr< UE::Slate::ItemsSource::IItemsSource< ItemType > > Pointer to the source data that we are observing Widgets/Views/STreeView.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

void ClearExpandedItems()

 Clears the entire set of expanded items. Widgets/Views/STreeView.h  

void ClearItemsSource()

   Widgets/Views/STreeView.h  

void ClearRootItemsSource()

   Widgets/Views/STreeView.h  

void Construct ( const FArguments& InArgs
)

 Construct this widget Widgets/Views/STreeView.h  

void GetExpandedItems ( TItemSet& ExpandedItems
) const

 Generates a set of items that are currently expanded. Widgets/Views/STreeView.h  

TArrayView< const ItemType > GetItems()

   Widgets/Views/STreeView.h  

TArrayView< const ItemType > GetRootItems()

   Widgets/Views/STreeView.h  

bool HasValidItemsSource()

   Widgets/Views/STreeView.h  

bool HasValidRootItemsSource()

   Widgets/Views/STreeView.h  

bool IsItemExpanded ( const ItemType& InItem
) const

   Widgets/Views/STreeView.h  

bool PopulateLinearizedItems ( TArrayView< const ItemType > InItemsSource,
TArray< ItemType >& InLinearizedItems,
TArray< FItemInfo >& NewDenseItemInfos,
TBitArray<> NeedsParentWire,
TItemSet& OutNewSelectedItems,
TSparseItemMap& NewSparseItemInfo,
bool bAddingItems,
int32 ParentIndex
)

 Given: an array of items (ItemsSource) each of which potentially has a child. Widgets/Views/STreeView.h  

int32 PopulatePinnedItems ( const TArray< ItemType >& InItemsSource,
TArray< ItemType >& InPinnedItems,
const STableViewBase::FReGenerateResults& Results
)

   Widgets/Views/STreeView.h  

void RequestTreeRefresh()

   Widgets/Views/STreeView.h  

void SetItemExpansion ( const ItemType& InItem,
bool InShouldExpandItem
)

 Set whether some data item is expanded or not. Widgets/Views/STreeView.h  
  Widgets/Views/STreeView.h  

void SetItemsSource ( TSharedRef<::UE::Slate::Containers::TObservableArray< ItemType > > InListItemsSource
)

   Widgets/Views/STreeView.h  

void SetItemsSource ( const TArray< ItemType >* InListItemsSource
)

   Widgets/Views/STreeView.h  

void SetRootItemsSource ( const TArray< ItemType >* InItemsSource
)

 Set the Root items. The tree will generate widgets to represent these items. Widgets/Views/STreeView.h  
Establishes a new list of root items being observed by the list. Widgets/Views/STreeView.h  
Set the RootItemsSource. The tree will generate widgets to represent these items. Widgets/Views/STreeView.h  

void SetSingleExpandedItem ( const ItemType& InItem
)

 Collapse all the items in the tree and expand InItem Widgets/Views/STreeView.h  

void SetStyle ( const FTableViewStyle* InStyle
)

   Widgets/Views/STreeView.h  

void SetTreeItemsSource ( const TArray< ItemType >* InItemsSource
)

 Set the TreeItemsSource. The Tree will generate widgets to represent these items. Widgets/Views/STreeView.h  

Overridden from SListView

Name Remarks Include Path Unreal Specifiers

virtual TSharedRef< ITableRow > GenerateNewWidget ( ItemType InItem
)

 Given a TreeItem, create a Widget to represent it in the tree view. Widgets/Views/STreeView.h  

Overridden from STableViewBase

Name Remarks Include Path Unreal Specifiers

virtual void RebuildList()

 Completely wipe existing widgets and fully regenerate them on next tick. Widgets/Views/STreeView.h  
Update generate Widgets for Items as needed and clean up any Widgets that are no longer needed. Widgets/Views/STreeView.h  

virtual void RequestListRefresh()

 Queue up a regeneration of the linearized items on the next tick. Widgets/Views/STreeView.h  

Overridden from SWidget

Name Remarks Include Path Unreal Specifiers

virtual FReply OnKeyDown ( const FGeometry& MyGeometry,
const FKeyEvent& InKeyEvent
)

   Widgets/Views/STreeView.h  

virtual void Tick ( const FGeometry& AllottedGeometry,
const double InCurrentTime,
const float InDeltaTime
)

 See SWidget::Tick() Widgets/Views/STreeView.h  

Overridden from ITypedTableView

Name Remarks Include Path Unreal Specifiers

virtual void Private_SignalSelectionChanged ( ESelectInfo::Type SelectInfo
)

 Notify the ItemsWidget that we changed its selection. Triggers as OnSelectionChanged(). Widgets/Views/STreeView.h  

Ask questions and help your peers Developer Forums

Write your own tutorials or read those from others Learning Library

On this page