Widgetsets support platform-sensitive development with the Lazarus IDE system. They act as adapter libraries that provide an interface between a platform-independent sourcecode written in Free Pascal and platform-specific system functions. Thus they allow for development of platform-native software without requiring to provide specific source code for different target platforms.
Widgetsets act as basis for the Lazarus Component Library (LCL).
Currently (June 2020), the development status of widget toolkit interfaces is roughly as follows:[1]
| Widget set | Supported operating systems | Status |
|---|---|---|
| Windows API, GDI | ||
| Windows CE API, GDI | ||
| GTK+ 1.2.x | Linux (via X11) | |
| GTK+ 2.8+ | Linux (X11 and framebuffer), Windows, and Mac OS X (via X11) | |
| GTK+ 3.x | As Gtk2 | |
| Qt 4.5+, 5.6+[2] | ||
| Windows, Windows CE, Linux (via X11) | ||
| Lazarus Custom Drawn Controls | ||