Virtual Tree View und Mauscursor

[Hawkeye219]

Thomas, ich habe den Code aus meinem vorigen Beitrag ein wenig umgebaut und erweitert:

Delphi-Quellcode:

const
  LINKCOLUMN = 2;

procedure TDemoForm.TreeDrawText(Sender: TBaseVirtualTree; TargetCanvas: TCanvas;
  Node: PVirtualNode; Column: TColumnIndex; const Text: WideString; const CellRect: TRect;
  var DefaultDraw: Boolean);
begin
  if IsHotNode(Node) then
    if (Column = LINKCOLUMN) and IsCursorInLinkColumn() then
      TargetCanvas.Font.Style := TargetCanvas.Font.Style + [fsUnderline]
    else
      TargetCanvas.Font.Style := TargetCanvas.Font.Style - [fsUnderline];
end;

procedure TDemoForm.TreeMouseMove (Sender: TObject; Shift:  TShiftState; X, Y: Integer);
begin
  if IsHotNode(Tree.GetNodeAt(X, Y)) and IsCursorInLinkColumn() then
    Tree.Cursor := crHandPoint
  else
    Tree.Cursor := crDefault;
end;

procedure TDemoForm.TreeClick (Sender: TObject);
begin
  if IsHotNode(Tree.FocusedNode) and IsCursorInLinkColumn() then
    ShowMessage (Tree.Text[Tree.FocusedNode, LINKCOLUMN]);
end;

function TDemoForm.IsHotNode (aNode: PVirtualNode): Boolean;
begin
  Result := (toHotTrack in Tree.TreeOptions.PaintOptions)
        and Assigned(aNode) and (aNode = Tree.HotNode);
end;

function TDemoForm.IsCursorInLinkColumn: Boolean;
begin
  Result := (ColumnAtCursorPos() = LINKCOLUMN);
end;

function TDemoForm.ColumnAtCursorPos: TColumnIndex;
var
  P: TPoint;
begin
  P := Tree.ScreenToClient(Mouse.CursorPos);
  Result := Tree.Header.Columns.ColumnFromPosition(P);
end;

Gruß Hawkeye