Rather than having to maintain a collection of content items manually, you might want to just specify a search rule that updates a list of content items dynamically as new content gets added to the system. The content query form provides a convenient interface to edit such rules.

For example, you can specify a rule that finds the latest five articles from your site's sports subsection, and displays them on a "latest sports news" section of your site's front page.

In the standard configuration of Blueprint, you can use the query form to filter for content items according to the following aspects:

Furthermore, you can order the result set by different criteria, and you can specify a maximum number of hits in order to ensure proper layout on a column-based page design, for example.

Support for dynamic content queries is bundled in the Studio plugin, and the main component to use is ContentQueryForm.mxml. You can use the editor as shown in the following example.

<dcqe:ContentQueryForm bindTo="{config.bindTo}"
                       itemId="contentQueryForm"
                       forceReadOnlyValueExpression=
                               "{config.forceReadOnlyValueExpression}"
                       queryPropertyName="localSettings"
                       documentTypesPropertyName="documenttype"
                       sortingPropertyName="order">
  <dcqe:plugins>
     <ui:VerticalSpacingPlugin modifier=
                   "{SpacingBEMEntities.VERTICAL_SPACING_MODIFIER_200}"/>
  </dcqe:plugins>
  <dcqe:conditions>
    <dcqe:ModificationDateConditionEditor bindTo="{config.bindTo}"
      propertyName="freshness"
      group="attributes"
      documentTypes=
        "{['CMArticle','CMVideo','CMPicture','CMGallery','CMChannel']}"
      forceReadOnlyValueExpression="{config.forceReadOnlyValueExpression}"
      sortable="true">
      <dcqe:timeSlots>
        <fx:Object name="sameDay"
          text="{resourceManager.getString(
                 'com.coremedia.blueprint.base.queryeditor.QueryEditor',
                 'DCQE_text_modification_date_same_day')}"
          expression="TODAY"/>
        <fx:Object name="sevenDays"
          text="{resourceManager.getString(
                 'com.coremedia.blueprint.base.queryeditor.QueryEditor',
                 'DCQE_text_modification_date_seven_days')}"
          expression="7 DAYS TO NOW"/>
        <fx:Object name="thirtyDays"
          text="{resourceManager.getString(
                 'com.coremedia.blueprint.base.queryeditor.QueryEditor',
                 'DCQE_text_modification_date_thirty_days')}"
          expression="30 DAYS TO NOW"/>
      </dcqe:timeSlots>
    </dcqe:ModificationDateConditionEditor>
    ...
  </dcqe:conditions>
</dcqe:ContentQueryForm>

In the example, the editor is configured to allow only for a single condition (a content item's modification date). You may combine the existing condition editors - there are predefined conditions for context, date ranges, and taxonomy links - or even write your own condition editors by extending ConditionEditorBase.as. Each condition editor provides the user interface for editing the respective condition, and must persist the actual search query fragment in a string property that will be written to the respective struct property. Also, all condition editors support the configuration of a list of document types that this condition may apply to. See the API documentation for the package com.coremedia.blueprint.base.queryeditor.conditions for details.

When rendering the result of a search query in your CAE application, you can use SettingsStructToSearchQueryConverter.java to convert the search component that the editor stores in the struct property to an actual search query. See CMQueryListImpl.java for an example.

Figure 6.1. Content Query Form