TreeSelectionModelIndexesChangedEventArgs Class
Definition
Holds data for the Avalonia.Controls.Selection.ITreeSelectionModel.IndexesChanged event.
public class TreeSelectionModelIndexesChangedEventArgs
Remarks
This event is raised when indexes in the selection model change due to insertions, removals, or reordering in the underlying data source. It provides information about which range of indexes was affected and how they were shifted.
Constructors
| Name | Description |
|---|---|
| TreeSelectionModelIndexesChangedEventArgs | Initializes a new instance of the Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs class. |
TreeSelectionModelIndexesChangedEventArgs Constructor
Initializes a new instance of the Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs class.
public TreeSelectionModelIndexesChangedEventArgs(Avalonia.Controls.IndexPath parentIndex, int startIndex, int endIndex, int delta)
Parameters
parentIndex Avalonia.Controls.IndexPath
The index path of the parent item whose children were affected.
startIndex int
The index at which the change started.
endIndex int
The index at which the change ended.
delta int
The number of items added or removed.
Remarks
The delta parameter will be positive when items are added and
negative when items are removed.
The affected range is from startIndex (inclusive) to
endIndex (exclusive).
Properties
| Name | Description |
|---|---|
| Delta | Gets the delta of the change; i.e. the number of indexes added or removed. |
| EndIndex | Gets the exclusive end index of the range of indexes that changed. |
| ParentIndex | Gets the index of the parent item. |
| StartIndex | Gets the inclusive start index of the range of indexes that changed. |
Delta Property
Gets the delta of the change; i.e. the number of indexes added or removed.
public int Delta { get; set; }
Value
A positive value indicates items were added; a negative value indicates items were removed.
Remarks
When items are added, Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs.Delta represents the number of items inserted.
When items are removed, Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs.Delta is negative and its absolute value represents the number of items removed. This value is used to adjust index paths that point to items after the change.
EndIndex Property
Gets the exclusive end index of the range of indexes that changed.
public int EndIndex { get; set; }
Remarks
This is one past the last index affected by the change. The range of affected indexes is from Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs.StartIndex (inclusive) to Avalonia.Controls.Selection.TreeSelectionModelIndexesChangedEventArgs.EndIndex (exclusive).
ParentIndex Property
Gets the index of the parent item.
public Avalonia.Controls.IndexPath ParentIndex { get; set; }
Remarks
For changes at the root level, this will be an empty index path.
StartIndex Property
Gets the inclusive start index of the range of indexes that changed.
public int StartIndex { get; set; }
Remarks
This is the first index affected by the change.