TableView Deep Dive

TableView displays infinitely-sized tabular data from any ITableSource and supports keyboard/mouse navigation, multi-cell selection, column styling, and checkbox columns.

Table of Contents

• Data Sources
• Selection Model
• Key & Mouse Bindings
• Rendering & Scrolling
• Column Styling
• Checkbox Columns
• Tree Tables
• Events

Data Sources

TableView does not own data. Assign an ITableSource to the Table property.

ITableSource

The core interface. Implement it to bridge any data model into a TableView:

public interface ITableSource
{
    int Rows { get; }
    int Columns { get; }
    string [] ColumnNames { get; }
    object this [int row, int col] { get; }
}

Built-in Implementations

DataTable Example

DataTable dt = new ();
dt.Columns.Add ("Name");
dt.Columns.Add ("Age", typeof (int));
dt.Rows.Add ("Alice", 30);
dt.Rows.Add ("Bob", 25);

TableView tv = new () { Table = new DataTableSource (dt) };

Object Collection Example

TableView tv = new ()
{
    Table = new EnumerableTableSource<Process> (
        Process.GetProcesses (),
        new Dictionary<string, Func<Process, object>> ()
        {
            { "ID", p => p.Id },
            { "Name", p => p.ProcessName },
            { "Threads", p => p.Threads.Count },
        })
};

CSV Example

DataTable dt = new ();
string [] lines = File.ReadAllLines (filename);

foreach (string h in lines [0].Split (','))
{
    dt.Columns.Add (h);
}

foreach (string line in lines.Skip (1))
{
    dt.Rows.Add (line.Split (','));
}

TableView tv = new () { Table = new DataTableSource (dt) };

Selection Model

TableView implements IValue<TableSelection?> to expose the complete selection state as a single value.

Key Types

Cursor

The cursor is the active cell — the anchor for navigation. Access it via Value.Cursor (Point where X = column index, Y = row index).

Move the cursor programmatically with SetSelection (col, row, extend).

Multi-Selection

When MultiSelect is true (the default), users can create rectangular selection regions:

• Shift+Arrow — extends a region from the cursor to the new position
• Ctrl+Click — unions the clicked cell as an independent extended selection
• Space (Command.ToggleExtend) — toggles the current cell's IsExtended state
• Ctrl+A — selects all cells

Extended regions (IsExtended = true) persist through keyboard navigation. Non-extended regions are cleared on the next cursor move.

FullRowSelect

When FullRowSelect is true, entire rows are selected instead of individual cells. All cells in the cursor's row are reported as selected by GetAllSelectedCells () and IsSelected ().

Reading the Selection

// Cursor position
Point cursor = tv.Value!.Cursor; // (col, row)

// All selected cell coordinates
IEnumerable<Point> cells = tv.GetAllSelectedCells ();

// Check if a specific cell is selected
bool sel = tv.IsSelected (col, row);

Key & Mouse Bindings

Default Key Bindings

Default Mouse Bindings

Customizing Bindings

TableView uses the standard KeyBindings and MouseBindings infrastructure. Override DefaultKeyBindings (static) or instance-level bindings.

Rendering & Scrolling

TableView renders only the visible portion of the table. Horizontal and vertical scrolling is handled via ColumnOffset and RowOffset (backed by Viewport).

Table Rendering Model

1. Header — column names with optional overline, underline, and vertical separators (controlled by TableStyle)
2. Data rows — rendered from RowOffset until viewport is filled
3. Columns — rendered from ColumnOffset right, each column sized by content width (clamped by MinCellWidth / MaxCellWidth and per-column ColumnStyle)

TableStyle

TableStyle controls the visual appearance:

EnsureCursorIsVisible

After programmatic cursor changes, call EnsureCursorIsVisible () to scroll the viewport so the cursor cell is on screen. Update () does this automatically.

Column Styling

Use TableStyle.ColumnStyles to customize individual columns:

tv.Style.ColumnStyles [2] = new ColumnStyle
{
    Alignment = Alignment.End,
    MaxWidth = 20,
    MinWidth = 5,
    Format = "C2",        // currency format
    ColorGetter = args => args.CellValue is int v && v < 0
        ? new Scheme () { Normal = new (Color.Red, Color.Black) }
        : null
};

ColumnStyle Properties

Checkbox Columns

Wrap any ITableSource with a checkbox column using CheckBoxTableSourceWrapperByIndex or CheckBoxTableSourceWrapperByObject<T>:

// By row index
CheckBoxTableSourceWrapperByIndex checkSrc = new (tv, tv.Table!);
tv.Table = checkSrc;

// Read checked rows
HashSet<int> checked = checkSrc.CheckedRows;

// By object property
CheckBoxTableSourceWrapperByObject<MyObj> checkSrc = new (
    tv,
    enumSource,
    obj => obj.IsSelected,
    (obj, val) => obj.IsSelected = val
);
tv.Table = checkSrc;

Space toggles checkboxes on the selected row(s). Clicking the checkbox column header toggles all rows. Set UseRadioButtons = true for single-select radio behavior.

Tree Tables

TreeTableSource<T> combines TreeView<T> expand/collapse with TableView column rendering:

TreeView<FileSystemInfo> tree = new ()
{
    TreeBuilder = new DelegateTreeBuilder<FileSystemInfo> (
        d => d is DirectoryInfo dir ? dir.GetFileSystemInfos () : [],
        d => d is DirectoryInfo),
    AspectGetter = f => f.Name
};

tree.AddObject (new DirectoryInfo ("/"));

TreeTableSource<FileSystemInfo> src = new (
    tv,
    "Name",
    tree,
    new Dictionary<string, Func<FileSystemInfo, object>> ()
    {
        { "Size", f => f is FileInfo fi ? fi.Length : 0 },
        { "Modified", f => f.LastWriteTime }
    });

tv.Table = src;

Arrow Left/Right collapse/expand nodes when the tree column has focus.

Events

TableView uses the standard IValue<T> and View event patterns:

Example: Reacting to Cursor Movement

tv.ValueChanged += (sender, e) =>
{
    if (e.NewValue is { } sel)
    {
        statusBar.Text = $"Row {sel.Cursor.Y}, Col {sel.Cursor.X}";
    }
};

Example: Handling Cell Activation

tv.Accepted += (sender, e) =>
{
    Point cursor = tv.Value!.Cursor;
    object cellValue = tv.Table! [cursor.Y, cursor.X];
    MessageBox.Query ("Cell", $"Value: {cellValue}", "OK");
};