Form definitions This section describes how to define application forms and program resources related to the presentation layer. Windows and formsThe section describes the concept of windows and forms in the language.Using imagesDescribes how to use pictures in the forms of your application.Accessibility guidelinesThis section describes the best practices to make your application accessible to disabled people.Message filesMessage files centralize strings and larger texts identified by a number, that can be used in programs.Action defaults filesAction defaults files allow to centralize action configuration parameters such as text, icon, accelerators and behavior options in XML format.Presentation stylesUse presentation styles to specify decoration attributes for window and form elements.Form specification filesForm specification files are the source files defining the layout and content of application forms.Form renderingThe section explains the layout rules to render forms on graphical front-ends.ToolbarsToolbars define a bar of buttons that appears at the top of application forms.TopmenusTopmenus define typical pull-down menus that appear at the top of application forms.