This is a z3cform widget based on the orginal n Archetypes widget which controls the vocabulary or display of other fields on an edit page. It needs to be given information about which fields to control and how to control them.
Feel free to help edit this document to help expain things better!
All the magic happens in the slave_fields parameter which should be a sequence of mappings. Each mapping is a description of a field controlled by this master field:
The name of the field to control on when the selection changes. The controlled field/widget may be of any type unless the 'vocabulary' or 'value' action is used. When the action is 'vocabulary', the field must use either a MultiSelectionWidget, a SelectionWidget, or a MasterSelectWidget any of which must have the 'format' parameter set to 'select' (this is the default only for MasterSelectWidget). For 'value', the widget must be simple enough to change the current value using element.value or elem.selectedIndex (StringWidget, SelectionWidget, AutoCompleteWidget, maybe others).
This is optional and will automatically be calculated if omited. It can be used to speicify the exact master field is that is rendered in the html document. Normally you will only need to set this for checkbox masters since their id has a -0 added like this: #form-widgets-checkboxfield-0. Note that this is a jQuery ID selector.
This is optional and will automatically be calculated if omited. It can be used to speicify the exact slave field name to control in the html form. Note that this is a jQuery ID selector, so something use something like this: #form-widgets-field
The type of action to perform on the slave field. This can be:
- 'vocabulary' -- which alters the vocabulary of the slave field using an
XMLHttpRequest call; 'hide' or 'show' which sets the slave field's visibility style attribute;
'enable' or 'disable' -- toggle which marks the target widget as enabled or disabled; or 'show' or 'hide' -- toggle which marks the target widget as show or hide; or 'value' -- which alters the value of another simple widget (StringWidget) on selection change using an XMLHttpRequest call. 'attr' -- which alters the value of a DOM element, specified by slaveID 'jquery' -- * NOT YET IMPLEMENTED * a complete jquery startment that will be sent back to the DOM to be executed.
- To use the 'vocabulary' action, the
slave field must meet the widget requirements stated above. To use the 'enable'/'disable' actions, the field must use a HTML widget that can be enabled/disabled.
The name of a method to call to retrieve the dynamic vocabulary for the slave field, or the value for the slave field when 'value' is used. For 'vocabulary', this must return a DisplayList. For 'value, it must return a string or msg_id. The method must accept a parameter which will be used to pass the new value selected in the master widget. The name of this parameter defaults to 'master_value', but any name may be used as long as it is specified using the control_param element. Used only with 'action':'vocabulary' or 'action':'value'.
As described above, this is the name of the paramter used when calling the vocab_method. Used only with 'action':'vocabulary', 'action':'value', 'action':'attr' and 'action':'jquery'.
A sequence of values which when selected in the master widget cause the slave field/widget to be hidden, shown or disabled. The method used is determined by the 'action' element. Used only with 'action':'hide', 'action':'enable', 'action':'disable' or 'action':'show'. The value '()' (dont use quotes) will trigger on anything.
Boolean value to indictate the siblings of the slave field should be selected as well as the slave field itself. This field can only be used with 'action':'hide' or 'action':'show' and is useful for hidng the label as well the slave field.
The position in the slave slave field to start deleting entries from the selection box when the selection box gets refreshed with new data. The selection box options are deleted before the Ajax call so it can not be used until the call is complete. This can be useful to prevent a small select box from appearing is the first option is '-------------'. This field is optional and can only be used with 'action':'vocabulary'. This value is also crecked before initating an ajax request. The ajax request will not be executed if the master select length is equal to or less than this number to help prevent slave widgets executing out of order. Default value is 0.
A sequence of values which when selected in the master widget prevent the widget from iniating an ajax request. Use ('') as the value to prevent an ajax call if the select option value is ''. The default is ().
Boolean indicated if the master widget should initally be triggered on load. Default is true for everythin except vocabulary in which case it is false to prevent an itital ajax call which usually will not be needed.
A single MasterSelectWidget may control any number of slave fields, new fields are controlled by adding new mappings to the slave_fields list/tuple. A field which is the target of a MasterSelectWidget action may itself use a MasterSelectWidget to control other fields.
The MasterSelectDemo type includes a number of master and slave widgets in different configurations. It is disabled by default, but you may import it through portal_setup tool and test it by checking the "implicitly addable" checkbox for it in the MasterSelectDemo entry in the portal_types tool.
Enjoy!