Editing Widget toolkit (section)

==Overview==
[[File:SWT-on-mac.png|thumb|A window using the [[Standard Widget Toolkit]]]]
Some toolkits may be used from other languages by employing [[language binding]]s. [[Graphical user interface builder]]s such as e.g. [[Glade Interface Designer]] facilitate the authoring of GUIs in a [[WYSIWYG]] manner employing a [[user interface markup language]] such as in this case [[GtkBuilder]].

The GUI of a program is commonly constructed in a cascading manner, with graphical control elements being added directly to on top of one another.

Most widget toolkits use [[event-driven programming]] as a model for interaction.<ref>[http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.45.9491 Past, Present and Future of User Interface Software Tools]. Brad Myers, Scott E. Hudson, Randy Pausch, Y Pausch. ACM Transactions on Computer-Human Interaction, 2000. [https://www.cs.cmu.edu/~amulet/papers/futureofhciACM.pdf]</ref> The toolkit handles [[Event handler|user events]], for example when the user clicks on a [[Button (computing)|button]]. When an event is detected, it is passed on to the application where it is dealt with. The design of those toolkits has been criticized for promoting an oversimplified model of event-action, leading programmers to create error-prone, difficult to extend and excessively complex [[application code]].<ref name=Samek03b>{{cite web
 | title  = Who Moved My State?
 | author = Samek, Miro 
 | url    = http://www.ddj.com/cpp/184401643
 | publisher = C/C++ Users Journal, The Embedded Angle column
 | date   = April 2003}}</ref> [[Finite-state machine]]s and [[UML state machine|hierarchical state machines]] have been proposed as high-level models to represent the interactive state changes for reactive programs.