FLTK is a cross-platform user interface toolkit for X11, Win32, and MacOS X, developed using C++. It is designed to be fast, lightweight, and easy to use, and provides a wide range of built-in widgets and graphics primitives for creating GUI applications.
The Fl_Button class makes use of push, check (Fl_Check_Button), round (Fl_Round_Button), and "light" (Fl_Light_Button) button styles. These styles work in momentary (press and release), toggle (press on, press off) or radio (press one of many) modes, which makes the creation of any type of button possible with a single widget.
Developers can benefit from the Fl_Input_, Fl_Text_Display, and Fl_Help_View widgets, which are designed to provide simple-to-complex text input/output capabilities. The Fl_Text_Display widget is based on C++ version of the NEdit software's extensible text editor API.
Numerical input controls are available through the Fl_Valuator class, which includes scrollbars (Fl_Scrollbar) and sliders (Fl_Slider). The Fl_Menu_ class offers various menu-based controls, including menubars (Fl_Menu_Bar) and combo boxes (Fl_Choice).
Fl_Browser_ is the foundation for a variety of list controls. The Fl_Browser widget lists lines of plain text, while other widgets list files, widgets, and more.
Organizing user interfaces can be done with scroll areas (Fl_Scroll), tabs (Fl_Tabs), tiles (Fl_Tile), and wizards (Fl_Wizard). The FLTK project also provides standard dialogs for alerts, button choosers, color choosers, file choosers, help browsers, messages, passwords, and text input.
FLTK 1.1.x comes in two appearance schemes: "standard" and "plastic." FLTK 2.0 plans on expanding this by incorporating platform schemes and user-defined schemes. Colors and fonts automatically adapt to a user's preferences.
Version 1.1.9: N/A