Version: Unity 6.5 Alpha (6000.5)
LanguageEnglish
  • C#

BaseTreeViewController

class in UnityEngine.UIElements

/

Inherits from:UIElements.CollectionViewController

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Description

Base collection tree view controller. View controllers of this type are meant to take care of data virtualized by any BaseTreeView inheritor.

Properties

Property Description
baseTreeView View for this controller, cast as a BaseTreeView.
itemsSource Items for this tree.

Public Methods

Method Description
CanChangeExpandedState Determines whether the item with the specified ID can be expanded or collapsed.
CollapseAll Collapses all items in the tree and refreshes the view.
CollapseItem Collapses the item with the specified ID, hiding its children. Allows to collapse the whole hierarchy under that item.
CollapseItemByIndex Collapses the item with the specified index, hiding its children. Allows to collapse the whole hierarchy under that item.
Exists Checks if an ID exists within this tree.
ExpandAll Expands all items in the tree and refreshes the view.
ExpandItem Expands the item with the specified ID, making its children visible. Allows to expand the whole hierarchy under that item.
ExpandItemByIndex Expands the item with the specified index, making his children visible. Allows to expand the whole hierarchy under that item.
GetAllItemIds Returns all item IDs that can be found in the tree, optionally specifying root IDs from where to start.
GetChildIndexForId Gets the child index under the parent of the item with the specified ID.
GetChildrenIds Get all children of a specific ID in the tree.
GetChildrenIdsByIndex Gets the children IDs of the item with the specified index.
GetIdForIndex Returns the ID for a specified index in the visible items source.
GetIndentationDepth Returns the depth of the element at that ID.
GetIndentationDepthByIndex Return the depth of the element at that index.
GetIndexForId Returns the index in the source of the item, by ID.
GetParentId Returns the parent ID of an item, by ID.
GetRootItemIds Returns the root items of the tree, by IDs.
GetTreeItemsCount Get the number of items in the whole tree.
HasChildren Return whether the item with the specified ID has one or more child.
HasChildrenByIndex Return whether the item with the specified index has one or more child.
IsExpanded Return whether the item with the specified ID is expanded in the tree.
IsExpandedByIndex Return whether the item with the specified index is expanded in the tree.
Move Moves an item by ID, to a new parent and child index.
TryRemoveItem Removes an item by id.

Inherited Members

Properties

PropertyDescription
itemsSource The items source stored in a non-generic list.
view The view for this controller.

Public Methods

MethodDescription
Dispose Called when this controller is not longer needed to provide a way to release resources.
GetItemForId Returns the item with the specified ID.
GetItemForIndex Returns the item with the specified index.
GetItemsCount Returns the expected item count in the source.
SetView Sets the view for this controller.

Protected Methods

MethodDescription
BindItem Binds a row to an item index.
DestroyItem Destroys a VisualElement when the view is rebuilt or cleared.
MakeItem Creates a VisualElement to use in the virtualization of the collection view.
PrepareView Initialization step once the view is set.
RaiseItemIndexChanged Invokes the itemIndexChanged event.
RaiseItemsSourceChanged Invokes the itemsSourceChanged event.
SetItemsSourceWithoutNotify Set the itemsSource without raising the itemsSourceChanged event.
UnbindItem Unbinds a row to an item index.

Events

EventDescription
itemIndexChanged Raised when an item in the source changes index. The first argument is source index, second is destination index.
itemsSourceChanged Raised when the itemsSource changes.

Is something described here not working as you expect it to? It might be a Known Issue. Please check with the Issue Tracker at issuetracker.unity3d.com.

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