TreeItemNode

Namespace: Hex1b

Assembly: Hex1b.dll

Render node for a single tree item. Managed by the parent TreeNode which handles tree structure and navigation.

public sealed class TreeItemNode : Hex1bNode

Inheritance

Object → Hex1bNode → TreeItemNode

Properties

CanExpand

Determines if this item can be expanded (has children or hints at having children).

Returns: Boolean

public bool CanExpand { get; }

CheckboxNode

Checkbox node for multi-select mode. Null when not in multi-select.

Returns: CheckboxNode

public CheckboxNode? CheckboxNode { get; set; }

Children

Child tree item nodes.

Returns: IReadOnlyList<TreeItemNode>

public IReadOnlyList<TreeItemNode> Children { get; set; }

Depth

The depth of this item in the tree (0 = root level). Set by the parent TreeNode during arrangement.

Returns: Int32

public int Depth { get; set; }

ExpandIndicatorNode

Expand indicator node (▶/▼). Null for leaf nodes.

Returns: IconNode

public IconNode? ExpandIndicatorNode { get; set; }

HasChildren

Whether this item has children (actual or hinted for lazy loading).

Returns: Boolean

public bool HasChildren { get; set; }

Icon

Optional icon/emoji prefix displayed before the label.

Returns: String

public string? Icon { get; set; }

IsExpanded

Returns: Boolean

public bool IsExpanded { get; set; }

IsFocusable

Returns true if this node can receive focus.

Returns: Boolean

public override bool IsFocusable { get; }

IsFocused

Gets or sets whether this node is currently focused. Only meaningful for focusable nodes (where IsFocusable is true).

Returns: Boolean

public override bool IsFocused { get; set; }

IsHovered

Gets or sets whether the mouse is currently hovering over this node. Set by Hex1bApp based on mouse position during each frame. Only set on focusable nodes (tracked via FocusRing hit testing).

Returns: Boolean

public override bool IsHovered { get; set; }

IsLastAtDepth

Array tracking whether ancestors at each depth are last children. Used by TreeNode to draw correct vertical guide lines.

Returns: Boolean[]

public bool[] IsLastAtDepth { get; set; }

IsLastChild

Whether this is the last child at its level. Used by TreeNode to draw correct guide lines.

Returns: Boolean

public bool IsLastChild { get; set; }

IsLoading

Whether children are currently being loaded (async lazy load in progress).

Returns: Boolean

public bool IsLoading { get; set; }

IsSelected

Returns: Boolean

public bool IsSelected { get; set; }

Label

The display label for this item.

Returns: String

public string Label { get; set; }

LoadingSpinnerNode

Spinner node for loading animation. Reconciled when IsLoading is true.

Returns: SpinnerNode

public SpinnerNode? LoadingSpinnerNode { get; set; }

SourceWidget

The source widget for this node.

Returns: TreeItemWidget

public TreeItemWidget? SourceWidget { get; set; }

UserIconNode

User icon node. Null if no icon specified.

Returns: IconNode

public IconNode? UserIconNode { get; set; }

Methods

ArrangeComposedNodes(int, int, Hex1bTheme)

Arranges the composed child nodes with real bounds. Called by TreeNode during arrangement.

Parameters:

• x (Int32): Starting X position for this item's content (after guides).
• y (Int32): Y position for this item.
• theme (Hex1bTheme): Theme for measuring elements.

public void ArrangeComposedNodes(int x, int y, Hex1bTheme theme)

ComputeSelectionState()

Computes the selection state for cascade selection mode. Returns Selected if this item and all descendants are selected, Indeterminate if some descendants are selected, None otherwise.

Returns: TreeSelectionState

public TreeSelectionState ComputeSelectionState()

ConfigureDefaultBindings(InputBindingsBuilder)

Configures the default input bindings for this node type. Override in derived classes to add default key bindings. These bindings can be inspected and modified by the user's callback.

Parameters:

• bindings (InputBindingsBuilder): The builder to add bindings to.

public override void ConfigureDefaultBindings(InputBindingsBuilder bindings)

GetChildren()

Gets the composed child nodes (indicator, checkbox, icon) for hit testing.

Returns: IEnumerable<Hex1bNode>

public override IEnumerable<Hex1bNode> GetChildren()

GetData<T>()

Gets the typed data associated with this item.

Returns: <T>

The data cast to the specified type.

public T GetData<T>()

GetDataOrDefault<T>(T?)

Gets the typed data, or a default value if not set or wrong type.

Parameters:

• defaultValue (<T>): The default value to return if data is not available.

Returns: <T>

The data or the default value.

public T? GetDataOrDefault<T>(T? defaultValue = default)

GetDisplayText()

Gets the display text for this item (icon + label).

Returns: String

public string GetDisplayText()

GetFocusableNodes()

Gets focusable nodes in this item's composed children. The checkbox is focusable for click handling.

Returns: IEnumerable<Hex1bNode>

public override IEnumerable<Hex1bNode> GetFocusableNodes()

MeasureCore(Constraints)

Override this method to implement measuring logic for this node.

Parameters:

• constraints (Constraints):

Returns: Size

protected override Size MeasureCore(Constraints constraints)

Render(Hex1bRenderContext)

Renders the node to the given context.

Parameters:

• context (Hex1bRenderContext):

public override void Render(Hex1bRenderContext context)

SetSelectionCascade(bool)

Sets the selection state for this item and all descendants (for cascade selection).

Parameters:

• selected (Boolean):

public void SetSelectionCascade(bool selected)

TryGetData<T>(out T)

Tries to get the typed data associated with this item.

Parameters:

• data (<T>): The data if successful, default otherwise.

Returns: Boolean

True if data exists and matches the type, false otherwise.

public bool TryGetData<T>(out T data)