Changes the default value of an attribute for a class. It can be any attribute, i.e. registered attributes or user custom attributes.
void IupSetClassDefaultAttribute(const char* classname, const char *name, const char *value); [in C]
iup.SetClassDefaultAttribute(classname, name, value: string) [in Lua]
classname: name of the class
name: name of the attribute
value: new default value.
If the value is DEFAULTFONT, DLGBGCOLOR, DLGFGCOLOR, TXTBGCOLOR, TXTFGCOLOR, LINKFGCOLOR or MENUBGCOLOR then the actual default value will be the global attribute of the same name consulted at the time the attribute is consulted.
Attributes that are not strings and attributes that have variable names, like those which has a complementary number, can NOT have a default value. Some attributes can NOT have a default value by definition.
If the new default value is (char*)-1, then the default value is set to be the system default if any is defined.