The list-rendering context
In IBM Digital Data Connector, the list-rendering context represents an aggregated data object. DDC plug-ins can use the data object to determine which data to load and how to filter and sort the data. We can create a list-rendering context by adding a [Plugin:ListRenderingContext] tag to the Web Content Manager designs. Parts of the context content are automatically completed by the DDC framework. These parts include the current portlet request and response, and the public Digital Data Connector render parameters. Other parts must be specified through parameters of the Plugin:ListRenderingContext tag. The general syntax of the tag is as follows:
[Plugin:ListRenderingContext action="" extension-id="" profile=""attribute="" key="" format="" separator="" escape="" prefix]
The parameters are described in the following list:
- action
- Mandatory. Identify the action to be run. Supported values:
- set
- Establish a new list-rendering context. We can nest list-rendering contexts. If specified, also set the extension-id parameter.
- remove
- Remove the current list-rendering context. If this list-rendering context was a nested list-rendering context, the outer list-rendering context becomes active again.
- getListProperty
- Extract properties of the bean list loaded for the current list-rendering context.
- getAttribute
- Extract individual attributes specified when creating the current list-rendering context.
- getFilter
- Retrieve the value of a specific DDC filter public render parameter.
- reloadProfiles
- Clear all DDC related caches and reload all list-rendering profiles. Useful in development environments for activating modifications in deployed list-rendering profiles.
- clearCaches
- Clear all DDC related caches. Useful in development environments for analyzing caching issues.
- exceptionOccured
- Check whether an exception occurred during bean list computation. The Web Content Viewer portlet renders the content of the ListRenderingContext plug-in tag with this action is only if an exception occurred the current list-rendering context was processed.
- getExceptionMessage
- Retrieve the message of an exception that occurred during bean list computation.
- extension-id
- Identify the specific DDC plug-in to handle this context. Mandatory with the setting action="set". For addressing the generic XML DDC plug-in, specify the value ibm.portal.ddc.xml.
- profile
- Identify the list-rendering profile to be used. This parameter becomes effective only in combination with the setting action="set". Mandatory when addingress the generic XML DDC plug-in in the extension-id parameter.
- attribute
- Multivalued attribute used to add extra information to the list-rendering context. Relevant for the setting action="set" only. The generic XML DDC plug-in supports a set of attributes. For details about these attributes, read The generic XML Digital Data Connector plug-in.
- key
- Identify a specific attribute or list property to be written to the markup. Relevant for the settings action="getListProperty" and action="getAttribute" only.
- format
- Formatting to be used when the plug-in writes list properties of type Date to the markup. Relevant for the setting action="getListProperty" only.
- separator
- Markup fragment to be written to the markup between the elements of a multivalued list property. The default value is a comma ( , ). Relevant for the settingaction="getListProperty" only.
- escape
- Escaping to apply for markup generated by the plug-in. Supported values: xml, json, javascript, and none. The default value is none. Relevant for action="getListProperty", action="getAttribute", action="getFilter", and action="getExceptionMessage" only.
- prefix
- Prefix for the DDC filter public render parameter to be retrieved. Relevant for action="getFilter" only.
The following table shows which actions the parameters support and whether they are mandatory.
For examples about how to set the list-rendering context, read the following topics.
Parameter Relevant for actions Parameter is mandatory with the actions in the previous column action N/A N/A extension-id set yes profile set Whether the profile parameter is mandatory depends on the value for the extension-id parameter. If we address the generic XML DDC plug-in, the profile parameter is mandatory. attribute set no key getListProperty, getAttribute yes format getListProperty no separator getListProperty, getFilter no escape getListProperty, getAttribute, getFilter no
- Set the list-rendering context
- Access list-rendering attributes and list properties
- Access error information
- Dynamic list-rendering contexts
Parent IBM Digital Data Connector (DDC) for WebSphere PortalRelated reference:
The generic XML Digital Data Connector plug-in