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TreeDataGridColumnHeadersPresenter Class

Definition​

Assembly:Avalonia.Controls.TreeDataGrid
Package:Avalonia.Controls.TreeDataGrid

Presents and manages column headers in a Avalonia.Controls.TreeDataGrid control.

public class TreeDataGridColumnHeadersPresenter

Inheritance: TreeDataGridColumnarPresenterBase<TreeDataGridColumn> -> TreeDataGridColumnHeadersPresenter

Remarks​

TreeDataGridColumnHeadersPresenter is responsible for creating, recycling, and arranging column headers horizontally at the top of a TreeDataGrid. It handles the virtualization of column headers, ensuring that only visible headers are realized in the visual tree to improve performance.

This presenter coordinates with the Avalonia.Controls.TreeDataGridColumns collection to manage column widths, measurement, and layout. It also handles column resizing by committing the actual column widths during arrangement.

Constructors​

NameDescription
TreeDataGridColumnHeadersPresenterNo summary available.

TreeDataGridColumnHeadersPresenter Constructor​

public TreeDataGridColumnHeadersPresenter()

Methods​

NameDescription
GetChildIndexGets the index of a logical child element.
TryGetTotalCountNo summary available.

GetChildIndex Method​

Gets the index of a logical child element.

public int GetChildIndex(Avalonia.LogicalTree.ILogical child)

Parameters​

child Avalonia.LogicalTree.ILogical

The logical child element.

Returns​

int

The index of the child element, or -1 if the element is not a column header or is not found.

Remarks​

This method is part of the Avalonia.LogicalTree.IChildIndexProvider interface implementation, which allows the presenter to provide indices for its logical children.

TryGetTotalCount Method​

public bool TryGetTotalCount(int& count)

Parameters​

count int&

Returns​

bool

Properties​

NameDescription
FrozenColumnCountGets or sets the number of frozen columns.

FrozenColumnCount Property​

Gets or sets the number of frozen columns.

public int FrozenColumnCount { get; set; }

Remarks​

Frozen columns do not scroll horizontally and remain visible at all times.

Fields​

FrozenColumnCountProperty Field​

Defines the Avalonia.Controls.Primitives.TreeDataGridColumnHeadersPresenter.FrozenColumnCount property.

public Avalonia.StyledProperty<int> FrozenColumnCountProperty

Events​

NameDescription
ChildIndexChangedOccurs when the index of a child element in the presenter changes.

ChildIndexChanged Event​

Occurs when the index of a child element in the presenter changes.

public event EventHandler<Avalonia.LogicalTree.ChildIndexChangedEventArgs> ChildIndexChanged

Remarks​

This event is raised when column headers are realized, unrealized, or when their indices change due to column insertions or removals.