Selection

Select cells, rows, and ranges with keyboard and mouse

TeeGrid provides flexible cell and range selection with visual feedback, keyboard navigation, and customizable appearance.

Basic Selection

Access the current selection:

// Get selected column and row
var
  Col: TColumn;
  Row: Integer;
begin
  Col := TeeGrid1.Selected.Column;
  Row := TeeGrid1.Selected.Row;
  
  if (Col <> nil) and (Row >= 0) then
    ShowMessage('Selected: ' + Col.Header.Text + ', Row ' + IntToStr(Row));
end;

Programmatic Selection

Set selection programmatically:

// Select specific cell
TeeGrid1.Selected.Column := TeeGrid1.Columns[3];
TeeGrid1.Selected.Row := 42;

// Or use Change method
TeeGrid1.Selected.Change(TeeGrid1.Columns[3], 42);

// Clear selection
TeeGrid1.Selected.Clear;

Selection Events

OnSelect

Fired when selection changes:

TeeGrid1.OnSelect := GridSelectionChanged;

procedure TForm1.GridSelectionChanged(Sender: TObject);
begin
  if TeeGrid1.Selected.Row >= 0 then
    Label1.Caption := 'Row: ' + IntToStr(TeeGrid1.Selected.Row)
  else
    Label1.Caption := 'No selection';
end;

Selection Appearance

Customize how selection looks:

// Selected cell/row colors
TeeGrid1.Selected.Format.Brush.Color := clHighlight;
TeeGrid1.Selected.Format.Brush.Visible := True;
TeeGrid1.Selected.Format.Font.Color := clHighlightText;
TeeGrid1.Selected.Format.Font.Style := [fsBold];

// Selection when grid doesn't have focus
TeeGrid1.Selected.UnFocused.Visible := True;
TeeGrid1.Selected.UnFocused.Format.Brush.Color := clSilver;
TeeGrid1.Selected.UnFocused.Format.Font.Color := clBlack;

Full Row Selection

Select entire rows instead of individual cells:

TeeGrid1.Selected.FullRow := True;

// Now clicking any cell selects the whole row

Range Selection

Select multiple cells:

// Enable range selection
TeeGrid1.Selected.Range.Enabled := True;

// Set range programmatically
TeeGrid1.Selected.Range.FromRow := 10;
TeeGrid1.Selected.Range.ToRow := 20;
TeeGrid1.Selected.Range.FromColumn := TeeGrid1.Columns[3];
TeeGrid1.Selected.Range.ToColumn := TeeGrid1.Columns[6];

Mouse Range Selection

Users can select ranges by dragging:

// Enable range selection
TeeGrid1.Selected.Range.Enabled := True;

// User can now:
// 1. Click and drag to select range
// 2. Shift+Click to extend selection
// 3. Shift+Arrow keys to extend selection

Checking Range Selection

if TeeGrid1.Selected.Range.Enabled then
begin
  ShowMessage('Range from row ' + 
              IntToStr(TeeGrid1.Selected.Range.FromRow) + 
              ' to ' + 
              IntToStr(TeeGrid1.Selected.Range.ToRow));
end;

Keyboard Navigation

Control Enter key behavior:

// TSelectingEnter options:
// - NextCell: Move to next cell
// - NextRow: Move to next row  
// - SameCell: Stay in same cell

TeeGrid1.Selected.EnterKey := TSelectingEnter.NextRow;

Scroll to View

Automatically scroll to show selection:

TeeGrid1.Selected.ScrollToView := True;

// Now when selection changes, grid scrolls to show it
TeeGrid1.Selected.Row := 1000;  // Scrolls to row 1000

Selectable Columns

Control which columns can be selected:

// Disable selection for specific column
TeeGrid1.Columns['Actions'].Selectable := False;

// User can't select cells in this column

Selection Hover

Highlight cells on mouse hover:

// Enable hover highlighting
TeeGrid1.Selected.Hover.Brush.Color := clYellow;
TeeGrid1.Selected.Hover.Brush.Visible := True;

Parent Font

Inherit selection font from parent:

TeeGrid1.Selected.ParentFont := True;

// Selection now uses grid's font
// Override with custom font:
TeeGrid1.Selected.ParentFont := False;
TeeGrid1.Selected.Format.Font.Size := 12;

Copy Selection

Copy selected data to clipboard:

// Copy current selection
TeeGrid1.Copy;

// Copy specific range
var
  Range: TGridSelection;
begin
  Range := TGridSelection.Create(nil);
  try
    Range.Range.Enabled := True;
    Range.Range.FromRow := 0;
    Range.Range.ToRow := 10;
    Range.Range.FromColumn := TeeGrid1.Columns[0];
    Range.Range.ToColumn := TeeGrid1.Columns[2];
    
    TeeGrid1.Copy(Range);
  finally
    Range.Free;
  end;
end;

Paste to Selection

Paste clipboard data:

// Paste at current selection
TeeGrid1.PasteSelected;

// Data from clipboard is pasted starting at selected cell

Multi-Selection

For advanced multi-selection scenarios:

// Range selection supports rectangular regions
TeeGrid1.Selected.Range.Enabled := True;

// Users can:
// - Click cell (start selection)
// - Shift+Click another cell (select range)
// - Ctrl+C to copy range
// - Ctrl+V to paste

Selection with Master-Detail

Each row group has independent selection:

procedure TForm1.DetailGroupCreated(const Sender, NewGroup: TRowGroup);
begin
  // Detail group has its own selection
  NewGroup.Selected.Format.Brush.Color := TAlphaColors.Lightblue;
  NewGroup.Selected.Format.Brush.Visible := True;
  
  // Handle detail selection
  NewGroup.OnChangedSelected := DetailSelectionChanged;
end;

procedure TForm1.DetailSelectionChanged(Sender: TObject);
var
  Group: TRowGroup;
begin
  Group := TRowGroup(Sender);
  
  if Group.Selected.Row >= 0 then
    ShowMessage('Detail row ' + IntToStr(Group.Selected.Row) + ' selected');
end;

Getting Selected Data

Retrieve data from selected cell:

var
  Value: String;
begin
  if (TeeGrid1.Selected.Column <> nil) and (TeeGrid1.Selected.Row >= 0) then
  begin
    Value := TeeGrid1.Data.AsString(TeeGrid1.Selected.Column, 
                                     TeeGrid1.Selected.Row);
    ShowMessage('Selected value: ' + Value);
  end;
end;

Selection Hit Testing

Check if a point is in selection:

var
  X, Y: Single;
begin
  X := Mouse.CursorPos.X;
  Y := Mouse.CursorPos.Y;
  
  if TeeGrid1.Grid.Current.SelectedContains(X, Y) then
    ShowMessage('Mouse is over selection');
end;

Empty Selection

Check if there’s a selection:

if TeeGrid1.Selected.IsEmpty then
  ShowMessage('Nothing selected')
else
  ShowMessage('Cell is selected');

Column Selection

Select entire columns (combined with FullRow):

procedure TForm1.SelectColumn(AColumn: TColumn);
begin
  TeeGrid1.Selected.Column := AColumn;
  TeeGrid1.Selected.Row := 0;
  TeeGrid1.Selected.Range.Enabled := True;
  TeeGrid1.Selected.Range.FromRow := 0;
  TeeGrid1.Selected.Range.ToRow := TeeGrid1.Data.Count - 1;
  TeeGrid1.Selected.Range.FromColumn := AColumn;
  TeeGrid1.Selected.Range.ToColumn := AColumn;
end;

Selection Context Menu

Show context menu on selection:

procedure TForm1.TeeGrid1MouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  if Button = mbRight then
  begin
    if TeeGrid1.Grid.Current.SelectedContains(X, Y) then
      PopupMenu1.Popup(Mouse.CursorPos.X, Mouse.CursorPos.Y);
  end;
end;

Previous Selection

Track previous selection:

var
  PreviousRow: Integer;

procedure TForm1.TeeGrid1Select(Sender: TObject);
begin
  ShowMessage('Changed from row ' + IntToStr(PreviousRow) + 
              ' to row ' + IntToStr(TeeGrid1.Selected.Row));
  
  PreviousRow := TeeGrid1.Selected.Row;
end;

Validate Selection

Prevent selection of certain cells:

procedure TForm1.TeeGrid1Select(Sender: TObject);
begin
  // Don't allow selecting first row
  if TeeGrid1.Selected.Row = 0 then
  begin
    TeeGrid1.Selected.Row := 1;  // Move to row 1
  end;
end;

Best Practices

• Use OnSelect to respond to selection changes
• Enable ScrollToView for better user experience
• Use FullRow := True for record-based data
• Use Range.Enabled := True for spreadsheet-like grids
• Customize UnFocused appearance so users can see selection when grid loses focus
• Make important columns non-selectable with Selectable := False
• Combine selection with Copy/Paste for data entry workflows
• Use IsEmpty to check for selection before accessing Column or Row
• Remember that each row group has its own selection in master-detail grids