NAME

       gs - The Graphics System for Erlang.

DESCRIPTION

   Warning:
       GS  is  not  recommended  for  use  in  new  applications.  Instead  we  recommend  WX for
       applications that need a graphical user interface.

       GS is deprecated and will be removed in the R16 release.

       The Graphics System, GS, is easy to learn and designed to be portable  to  many  different
       platforms.

       In  the  description  below,  the  type  gsobj() denotes a reference to a graphical object
       created with GS. Such a reference is either a GS object identifier  or  the  name  of  the
       object  (an atom), if such a name exists. The functions all return the specified values or
       {error,Reason} if an error occurs.

       Please refer to the GS User's Guide for a description of the different  object  types  and
       possible options.

EXPORTS

       config(GSObj, Options) -> ok

              Types:

                 GSOBj = gsobj()
                 Options = [Option] | Option
                  Option = {Key,Value}

              Configures a graphical object according to the specified options.

       create(ObjType, Parent) -> ObjId
       create(ObjType, Parent, Options) -> ObjId
       create(ObjType, Name, Parent, Options) -> ObjId

              Types:

                 ObjType = atom()
                 Parent = gsobj()
                 Name = atom()
                 Options = [Option] | Option
                  Option = {Key,Value}

              Creates  a  new  graphical object of the specified type as a child to the specified
              parent object. The object is configured according to the options and its identifier
              is returned. If no options are provided, default option values are used.

              If a name is provided, this name can be used to reference the object instead of the
              object identifier. The name is local to the process which creates the object.

              The following object types exist: window | button |  radiobutton  |  checkbutton  |
              label  |  frame  | entry | listbox | canvas | arc | image | line | oval | polygon |
              rectangle | text | menubar | menubutton | menu |  menuitem  |  grid  |  gridline  |
              editor | scale

       create_tree(Parent, Tree) -> ok

              Types:

                 Parent = gsobj()
                 Tree = [Object]
                  Object       =      {ObjType,Options}      |      {ObjType,Options,Tree}      |
                 {ObjType,Name,Options,Tree}

              Creates a hierarchy of graphical objects.

       destroy(GSObj) -> void()

              Types:

                 GSObj = gsobj()

              Destroys a graphical object and all its children.

       ObjType(Parent)
       ObjType(Parent, Options)
       ObjType(Name, Parent, Options)

              These functions are shorthand equivalents  of  create/2,  create/3,  and  create/4,
              respectively.

       read(GSObj, Key) -> Value

              Types:

                 GSObj = gsobj()
                 Key = atom()
                 Value = term()

              Returns the value of an option key for the specified graphical object.

       start() -> ObjId

              Starts GS, unless it is already started, and returns its object identifier.

       stop() -> void()

              Stops GS and closes all windows. This function is not the opposite of start/0 as it
              will cause all applications to lose their GS objects.