NSTableColumn

NSTableColumn is a class in the AppKit framework that represents a single column within an NSTableView. Each column carries its own identity, appearance, and sizing information, and together with other columns defines the structure of the table. The class is used in both cell-based and view-based table views, though its role differs slightly depending on the table's mode.

Key properties include the identifier, title, and sizing controls. The identifier is a NSUserInterfaceItemIdentifier that uniquely identifies the column within its table view and is commonly used by the data source and delegate to retrieve data or configure behavior for the column. The title or headerCell determines the text shown in the column’s header. Width, minWidth, and maxWidth govern the column’s size, while resizable indicates whether the user can adjust the width interactively. The column can also hold a headerCell (NSTableHeaderCell) and a dataCell (NSCell) used by cell-based tables to render and edit contents. In modern, view-based NSTableView implementations, the actual content for each row is provided by views (for example, NSTableCellView), but the column still supplies attributes and identifiers that its table view and delegate can reference.

Sorting support is provided via sortDescriptorPrototype, an NSSortDescriptor that defines how data should be ordered when the user clicks the column header. This descriptor typically uses the column’s identifier as the key.

NSTableColumn can be created programmatically or configured in Interface Builder, and is then added to an NSTableView’s columns array. It is read by the table view to manage rendering, editing, and sorting in concert with its data source and delegate.