ReAction GUI

ReAction GUI

ReAction GUI it is the name of the widget toolkit engine that is used in AmigaOS 3.5-4.1.

It is an evolution of ClassACT, which is an object oriented system of classes that enhanced the aspect of the Workbench 2.0 GUI of AmigaOS.



The first Amiga GUI called Workbench 1.0 and up to version 1.3 lacked a standardized unified look and feel, and often application developers had to write their own widgets (both buttons and menus) if they wanted to enhance standard basic widgets, with Intuition providing little support. With the release of AmigaOS 2.0 the system was shipped with gadtools.library, which provided standard widget sets, and the Amiga User Interface Style Guide, which explained how applications should be laid out for consistency. Intuition was improved with BOOPSI (Basic Object Oriented Programming system for Intuition) which enhanced the system with an object oriented interface with a system of classes in which every class individuate[clarification needed] a single widget or describes an interface event, and ASL (Amiga Standard Requester Library) which dealt with system dialog windows.

The introduction of BOOPSI led an evolution in which third-party developers realized their personal tools to improve the AmigaOS standard GUI; so were born new GUI systems such as MUI and ClassAct which then evolved into ReAction.



ClassAct is an object oriented system of classes and gadgets developed to replace and enhance the Amiga GadTools.library born with AmigaOS 3.1. Its main features are expandability and modularity. New classes and gadgets could be added to the system and improve it with new capabilities.

Classes of ClassACT

Main classes are:

  • window.class
  • requester.class
  • arexx.class

Main gadgets are:

  • button.gadget
  • checkbox.gadget
  • speedbar.gadget
  • space.gadget
  • slider.gadget
  • scroller.gadget
  • radiobutton.gadget
  • palette.gadget
  • listbrowser.gadget
  • layout.gadget
  • integer.gadget
  • getscreenmode.gadget
  • getfont.gadget
  • getfile.gadget
  • fuelgauge.gadget
  • clicktab.gadget
  • chooser.gadget
  • string.gadget
  • textfield.gadget

Various styles can be applied to ClassAct gadgets, such as 3D aspect. Gadgets could have bevel borders, the font have fallback option in case the default font is too large to fit the window on the screen, Pen number to use for labels and labels fonts could be set by the user, and many, many options like these.


ReAction is the official AmigaOS GUI builder since OS 3.5 days. Nowadays it is being built on top of Intuition, updated and has a better and more consistent look through the apps that use it.

ReAction system of classes and gadgets is almost the same as ClassACT. It is expandable and modular as the same as ClassAct. New classes and gadgets can be added to the system with ease to enhance its features.

A little example of this modularity could be new ReAction gadget class available that is piechart.gadget. The main purpose of this gadget is displaying the data distribution among various sources, like shares, disk capacity and free space, etc. on a graphical pie chart. Optional interaction from the user is also possible.

Examples of minimal code

Button and String gadgets

// Button gadget
#include <gadgets/layout.h>
#include <proto/layout.h>
#include <proto/button.h>
// Sample layout:
End,//Quit button gadget
// String gadget
#include <gadgets/layout.h>
#include <gadgets/string.h>
#include <proto/layout.h>
#include <proto/string.h>
#include <intuition/gadgetclass.h>
// Sample layout:
End,//String gadget

Other toolkits on Amiga

There are two main widget toolkits competing in the Amiga world. ReAction which is the default GUI toolkit chosen for AmigaOS 3.5-4.1 and for developing AmigaOS software, and MUI which is the default GUI toolkit chosen for MorphOS. AROS uses Zune toolkit which is an open source MUI clone.

Cygnix is a lightweight UNIX simulation environment for AmigaOS that comes with an X11 server Cygwin, and this has been used to port programs such as AbiWord or GIMP to the Amiga. A slightly related project is a GTK MUI wrapper which eventually will simplyfy porting of GTK based software.

Various multi-platforms graphics libraries and toolkits such as Cairo and SDL are also available on Amiga, and are the basics for creating new and enhanced Toolkits, new GUIs, new systems of widgets, etc.

There is also XML based toolkit, Feelin.

See also

External links

Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • Reaction — A reaction is usually any response caused by some other event:*Adverse drug reaction *Chemical reaction *Light reaction *Nuclear reaction *Reaction (physics), as defined by Newton s third law *Reflex reaction *Reactionary, a political tendencyThe …   Wikipedia

  • Gui De Dampierre — Pour les articles homonymes, voir Guy de Dampierre (homonymie). Gui ou Guy de Dampierre, né vers 1226, mort à Compiègne le 7 mars 1305, fut proclamé Comte de Flandre en 1253 par sa mère et devint comte effectif à la mort de cette… …   Wikipédia en Français

  • Gui de dampierre — Pour les articles homonymes, voir Guy de Dampierre (homonymie). Gui ou Guy de Dampierre, né vers 1226, mort à Compiègne le 7 mars 1305, fut proclamé Comte de Flandre en 1253 par sa mère et devint comte effectif à la mort de cette… …   Wikipédia en Français

  • Gui de Dampierre — Pour les articles homonymes, voir Guy de Dampierre (homonymie). Gui de Dampierre Gui de Dampierre à cheval, arborant les armes des comtes de Flandres …   Wikipédia en Français

  • Zune (GUI) — …   Википедия

  • XIA GUI — On ne possède que très peu d’informations sur la vie de Xia Gui: il était originaire des environs de Hangzhou et occupa une position officielle à l’Académie impériale de peinture sous le règne de l’empereur Ningzong (1195 1224). La peinture de… …   Encyclopédie Universelle

  • Liste von GUI-Bibliotheken — Inhaltsverzeichnis 1 Plattformübergreifende Bibliotheken 1.1 C 1.2 C++ 1.3 C# 1.4 Fortran …   Deutsch Wikipedia

  • Фрейм (элемент интерфейса программ) — Рама, иногда как Рамка или просто Фрейм (англ. Frame)  элемент (виджет) графического интерфейса пользователя, который является контейнером для других объектов. Очень схож с окном по своим свойствам, но отличается от него тем, что не… …   Википедия

  • Magic User Interface — Developer(s) Stefan Stuntz Initial release 1993; 18 years ago (1993) …   Wikipedia

  • AmigaOS 4 — A screenshot of AmigaOS 4.1 Update 2. Company / developer Hyperion Entertainment Programmed in C OS family …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”