50.3.6.1 Introduction to Native Widgets and Subwindow Glyphs

Traditionally Emacsen have hidden the GUI apparatus from the Lisp programmer, but in SXEmacs 22.1 the ability to embed autonomous GUI objects, called native widgets, in text was added to Lisp. They are handled as glyphs. Unlike traditional XEmacs glyphs such images and strings, native widgets are opaque to SXEmacs, and must be able to redraw themselves because they are implemented as subwindows, not as graphics drawn by SXEmacs into the text window.

Primitive widgets are coded in C using the underlying GUI toolkit, and thus are beyond the scope of the SXEmacs Lisp Reference Manual. However, composite widgets can be created in Lisp using “layouts,” which are horizontal or vertical arrays of subwidgets. For example, the search dialog is formatted using layouts.