.. _pages/class_quickref#class_declaration_quick_ref:

Class Declaration Quick Ref
***************************

.. note::

  The variants and settings key is deprecated. Please use the environment key instead.

This is a quick reference for the various features of a qooxdoo class declaration. It uses an EBNF-like syntax.

Properties, a particular part of the class declaration, have quite an extensive sub-spec, and are therefore factored out to their :doc:`own page <properties_quickref>`.

::

    class_decl      := 'qx.Class.define' '(' '"' <name.space.ClassName> '"' ','
                         '{' { feature_spec ',' } '}'
                       ')'

    feature_spec    := 
                       'type'        ':' type_spec        |
                       'extend'      ':' extend_spec      |
                       'implement'   ':' implement_spec   |
                       'include'     ':' include_spec     |
                       'construct'   ':' construct_spec   |
                       'statics'     ':' statics_spec     |
                       'properties'  ':' properties_spec  |
                       'members'     ':' members_spec     |
                       'settings'    ':' settings_spec    |
                       'variants'    ':' variants_spec    |
                       'environment' ':' environment_spec |
                       'events'      ':' events_spec      |
                       'defer'       ':' defer_spec       |
                       'destruct'    ':' destruct_spec 

    type_spec        := 'static' | 'abstract' | 'singleton'
                     
    extend_spec      := <name.of.SuperClass>
                     
    implement_spec   := <name.of.Interface> | 
                        '[' <name.of.Interface1> ',' <name.of.Interface2> ',' 
                            ... ']'
                     
    include_spec     := <name.of.Mixin> | 
                        '[' <name.of.Mixin1> ',' <name.of.Mixin2> ',' ... ']'
                     
    construct_spec   := js_function_value
                     
    statics_spec     := c_map
                     
    properties_spec  := ? see separate properties quick ref ?
                     
    members_spec     := c_map
                     
    settings_spec    := '{' { '"' <settings_name> '"' ':' 
                                  ( js_primitive_value | js_reference_value ) 
                                  ',' } '}'
                                  
                     
                     
                     
    environment_spec := '{' { '"' <environment_name> '"' ':' 
                                  ( js_primitive_value | js_reference_value ) 
                                  ',' } '}'
                     
                     
                     
    variants_spec    := 'qx.Variant.select' '(' '"' <variantName> '"' ','
                          '{' { '"' <variantvalue_spec> '"' ':' <selectValue> 
                                    ',' } '}'
                        ')'
                     
    events_spec      := '{' { '"' <event_name> '"' ':' '"' qx_event_type '"' 
                             ',' } '}'
                     
    defer_spec       := js_function_value
                     
    destruct_spec    := '{' 
                         [ 'this._disposeFields'     '(' <fields_list> ')' ';' ]
                         [ 'this._disposeObjects'    '(' <fields_list> ')' ';' ]
                         [ 'this._disposeObjectDeep' '(' <deep_field> ')'      ]
                         '}'
                     
    c_map            := '{' { <key> ':' [ js_primitive_value | 
                                          js_reference_value | 
                                          js_function_value  |
                                          variants_spec      ] ',' } '}'

    js_function_value   := ? Javascript anonymous function 'function (...) {...}' ?
    js_primitive_value  := ? any value from the Javascript primitive types ?
    js_reference_value  := ? any value from the Javascript reference types ?
    qx_event_type       := ? any qooxdoo event type class name, e.g. 
                             'qx.event.type.DataEvent' ?

