Interaction

Mouse and keyboard navigation

TTMSFNCTreeView responds to mouse clicks and keyboard navigation out of the box:

• Click a node to select it.
• Up/Down, Home, End, Page Up/Down move selection.
• Left/Right keys collapse and expand nodes.
• Clicking the expand/collapse icon has the same effect.

Multi-select

Enable multi-selection, enumerate the selected nodes, or select everything:

uses
  FMX.Dialogs, FMX.TMSFNCTreeView, FMX.TMSFNCTreeViewData;

procedure TForm1.EnableMultiSelect;
begin
  TreeView1.Interaction.MultiSelect := True; // Ctrl+click or Shift+click to extend
end;

procedure TForm1.ShowSelectedNodes;
var
  I: Integer;
begin
  for I := 0 to TreeView1.SelectedNodeCount - 1 do
    ShowMessage(TreeView1.SelectedNodes[I].Text[0]);
end;

procedure TForm1.SelectEverything;
begin
  TreeView1.SelectAllNodes;        // collection-based
  TreeView1.SelectAllVirtualNodes; // virtual
end;

Mouse wheel sensitivity

Control how much the tree scrolls per wheel notch:

uses
  FMX.TMSFNCTreeView;

procedure TForm1.SetWheelSensitivity;
begin
  TreeView1.Interaction.MouseWheelDelta := 2; // scroll 2 node heights per notch
end;

---

Inplace editing

Enable editing per column via the EditorType property. You can also blank the editor when editing starts (via OnGetNodeText with AMode = tntmEditing) and reject a value before it commits (via OnBeforeUpdateNode):

uses
  FMX.TMSFNCTreeView, FMX.TMSFNCTreeViewData;

procedure TForm1.EnableInplaceEditors;
begin
  TreeView1.Columns[0].EditorType := tcetEdit;     // standard edit
  TreeView1.Columns[1].EditorType := tcetComboBox; // combo with a fixed list
  TreeView1.Columns[1].EditorItems.Add('Option A');
  TreeView1.Columns[1].EditorItems.Add('Option B');
end;

// Blank the editor when editing starts.
procedure TForm1.TreeView1GetNodeText(Sender: TObject;
  ANode: TTMSFNCTreeViewVirtualNode; AColumn: Integer;
  AMode: TTMSFNCTreeViewNodeTextMode; var AText: string);
begin
  if AMode = tntmEditing then
    AText := '';
end;

// Reject an empty value before it commits.
procedure TForm1.TreeView1BeforeUpdateNode(Sender: TObject;
  ANode: TTMSFNCTreeViewVirtualNode; AColumn: Integer;
  var AText: string; var ACanUpdate: Boolean);
begin
  if AText = '' then
    ACanUpdate := False;
end;

Start editing with a click on the text or by pressing F2.

Custom editor

Supply any TControl subclass as the inplace editor:

uses
  System.SysUtils, FMX.StdCtrls, FMX.TMSFNCTreeView, FMX.TMSFNCTreeViewData;

procedure TForm1.EnableCustomEditor;
begin
  TreeView1.Columns[1].CustomEditor := True;
end;

procedure TForm1.TreeView1GetInplaceEditor(Sender: TObject;
  ANode: TTMSFNCTreeViewVirtualNode; AColumn: Integer;
  var ATransparent: Boolean;
  var AInplaceEditorClass: TTMSFNCTreeViewInplaceEditorClass);
begin
  AInplaceEditorClass := TTrackBar;
end;

procedure TForm1.TreeView1BeforeUpdateNode(Sender: TObject;
  ANode: TTMSFNCTreeViewVirtualNode; AColumn: Integer;
  var AText: string; var ACanUpdate: Boolean);
begin
  AText := FloatToStr((TreeView1.GetInplaceEditor as TTrackBar).Value);
end;

---

Lookup

When Interaction.Lookup.Enabled is True, typing alphanumeric characters navigates to the node whose text starts with the typed string:

uses
  FMX.TMSFNCTreeView;

procedure TForm1.EnableLookup;
begin
  TreeView1.Interaction.Lookup.Enabled := True;
end;

---

Filtering

Filtering hides nodes that don't match a condition while keeping their ancestors visible so the tree stays navigable. Enable column-header filter dropdowns or apply a programmatic filter via the Filter collection.

uses
  FMX.TMSFNCTreeView;

procedure TForm1.ConfigureColumnFiltering;
begin
  TreeView1.Columns[0].Filtering.Enabled := True;  // adds a filter dropdown button
  TreeView1.Columns[1].Filtering.Enabled := False;
end;

procedure TForm1.ClearFilters;
begin
  TreeView1.RemoveFilters;
end;

Dropdown filter

Setting Filtering.Enabled (shown above) adds a filter button to the column header. Clicking it shows a dropdown list of unique values; selecting one filters the tree.

Programmatic filter

procedure TForm1.ApplyFilter;
var
  f: TTMSFNCTreeViewFilterData;
begin
  TreeView1.Filter.Clear;

  f := TreeView1.Filter.Add;
  f.Column := 0;
  f.Condition := '*A*';  // wildcard match on column 0

  f := TreeView1.Filter.Add;
  f.Column := 1;
  f.Condition := '>= 2010';  // range match on column 1

  TreeView1.ApplyFilter;
end;

Note

When a child node matches the filter condition, its entire parent chain is also shown so the tree structure remains navigable.

Call TreeView1.RemoveFilters to remove all active filters (see ClearFilters above).

---

Sorting

Enable click-to-sort on a column, or sort programmatically with a chosen direction:

uses
  FMX.TMSFNCTreeView;

procedure TForm1.EnableSorting;
begin
  TreeView1.Columns[0].Sorting := tcsRecursive; // click-to-sort, also sorts children
end;

procedure TForm1.SortProgrammatically;
begin
  // parameters: column index, recursive, case-sensitive, sort direction
  TreeView1.Sort(0, True, False, nsmDescending);
end;

---

Clipboard

uses
  FMX.TMSFNCTreeView;

procedure TForm1.ConfigureClipboard;
begin
  TreeView1.Interaction.ClipboardMode := tcmFull;
  // tcmTextOnly copies text only; tcmFull copies text, icons, and check states
end;

Cut/Copy/Paste are handled via standard keyboard shortcuts (Ctrl+X, Ctrl+C, Ctrl+V). When pasting, the focused node becomes the parent of the pasted nodes; if no node is focused, pasted nodes are added at root level.

---

Reordering and drag-and-drop

Reordering within the same level

uses
  FMX.TMSFNCTreeView;

procedure TForm1.EnableReorder;
begin
  TreeView1.Interaction.Reorder := True; // drag an already-selected node to a new position
end;

procedure TForm1.EnableDragDrop;
begin
  TreeView1.Interaction.DragDropMode := tdmMove; // or tdmCopy; takes precedence over reorder
end;

Drag-and-drop

Set Interaction.DragDropMode to tdmMove or tdmCopy (shown above). Drag-and-drop takes precedence over reorder and supports moving nodes between two different TTMSFNCTreeView instances.

Drag-and-drop events: OnBeforeDropNode, OnAfterDropNode, OnAfterReorderNode.

---

Combined example: filtering + sorting + editing

  var ACanUpdate: Boolean);
begin
  // Validate or transform the text before it is committed
  if (AColumn = 0) and (AText = '') then
    ACanUpdate := False;  // reject empty text
end;

// Clipboard
procedure TForm1.SetupClipboard;
begin

Interaction property reference

Property	Description
ClipboardMode	tcmNone, tcmTextOnly, tcmFull
ColumnAutoSizeOnDblClick	Autosize a column by double-clicking the header splitter
ColumnSizing	Allow the user to resize columns by dragging
DragDropMode	tdmNone, tdmMove, tdmCopy
ExtendedEditable	Allow editing extended (section-header) nodes
ExtendedSelectable	Allow selecting extended nodes
KeyboardEdit	Start editing with F2 or direct typing
Lookup.Enabled	Type-to-navigate
MouseEditMode	When mouse click starts editing
MouseWheelDelta	Scroll sensitivity (node heights per wheel notch)
MultiSelect	Allow Ctrl/Shift multi-selection
ReadOnly	Disable all editing
Reorder	Enable drag-reorder within the same level
TouchScrolling	Enable inertial touch scroll

Related API

• TTMSFNCTreeView — Sort, Filter, ApplyFilter, RemoveFilters, SelectAllNodes
• TTMSFNCTreeViewData — TTMSFNCTreeViewFilterData

See also

• Columns and groups — per-column filtering and sorting configuration
• Nodes — node types and structure