NSCell

NSCell is a class in Apple's AppKit that represents the content and behavior of a single element in a cell-based user interface. It is the primitive building block used by controls that arrange multiple items in a grid or list, such as matrix-like controls and form elements. NSCell is an abstract or base class; concrete appearance and interaction are provided by its descendants such as NSTextFieldCell, NSImageCell, and NSButtonCell.

An NSCell is responsible for drawing its content, managing basic interaction, and optionally supporting in-place editing. It can hold a text string and/or an image, and can store an associated representedObject to link to model data. Cells also maintain state information such as highlighted or enabled, and in controls that support actions, a cell can target and trigger an action when activated.

Subclasses implement specific drawing and editing behavior; for example, NSTextFieldCell draws and edits text, NSImageCell displays an image, and NSButtonCell handles button-like interactions and can invoke a target-action pair. Because many controls in AppKit expose a cell property, NSCell provides a common interface for drawing and state management while the actual behavior is defined by the concrete cell type.

NSCell originated in NeXTSTEP and remains part of AppKit for backward compatibility with older code. In modern Cocoa development, view-based controls have become the norm, but cell-based constructs and NSCell classes are still available in the API for legacy code and certain controls.

Developers configure NSCell instances and assign them to controls that support cell-based content; a single cell can be reused to render many items in a grid or list.