Products.MasterSelectWidget 0.4

MasterSelectWidget

This is an 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.

To install it just extract into your products directory, restart zope, and install it with the QuickInstaller.

To use it just create a field like:

StringField(
    name='master_field',
    default='',
    vocabulary=DisplayList(
        (('week', 'Week'),
         ('wedding','Wedding'),
         ('winona','Winona'),
         ('winter', 'Winter'),
         ('weather','Weather'),
         ('cow', 'Cow'),
        ),
    ),
    widget=MasterSelectWidget(
        label='Test Widget',
        description='Test this',
        slave_fields=(
            {'name': 'slave_field_name',
             'action': 'vocabulary',
             'vocab_method': 'mySlaveVocabularyMethod',
             'control_param': 'my_method_parameter',
            },
        ),
    ),
),

You can use any field type compatible with a normal SelectWidget. And you may use any of the normal SelectWidget parameters (except ‘format’, which must be set to ‘select’). It will appear and behave like a normal SelectWidget, but changes in this widget will affect the widgets described in the slave_fields parameter.

Parameters

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:

name –

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).

action –

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’ which marks the target widget as enabled or disabled; or ‘value’ which alters the value of another simple widget (StringWidget) on selection change using an XMLHttpRequest call. 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.

vocab_method –

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’.

control_param –

As described above, this is the name of the paramter used when calling the vocab_method. Used only with ‘action’:’vocabulary’ or ‘action’:’value’.

hide_values –

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’.

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 add and test it by checking the “implicitly addable” checkbox for it in the MasterSelectDemo entry in the portal_types tool.

Enjoy!

Credits

Author –

Alec Mitchell: apm13@columbia.edu

Contributor –

Dorneles Tremea: deo@plonesolutions.com