Component visibility in the Share user interface can be controlled by Evaluators.
Architecture Information:Share Architecture
An evaluator is used by other extension points, such as Document Library Actions and Surf Extension Modules, to control when they should display or hide something. Custom evaluators are either configured or coded in Java. The following is an example of an evaluator that is configured as a Spring Bean:
<bean parent="evaluator.doclib.action.propertyNotNull"> <property name="property" value="exif:exposureTime"/></bean>In this case a new custom evaluator with IDevaluator.doclib.metadata.hasExposure is created. It is based on the out-of-the-boxpropertyNotNull evaluator, which takes aproperty parameter with the content model property that should be checked fornull. This evaluator is now ready to use in for example a Document Library Action definition.
If the evaluator is a bit more complex, and there is no existing evaluator that it can be based on, then we can implement the evaluator in Java as in the following example:
import org.alfresco.error.AlfrescoRuntimeException;import org.alfresco.web.evaluator.BaseEvaluator;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.json.simple.JSONArray;import org.json.simple.JSONObject;public class CheckIfDocIsEmailedEvaluator extends BaseEvaluator { private static Log logger = LogFactory.getLog(CheckIfDocIsEmailedEvaluator.class); private static final String ASPECT_EMAILED = "cm:emailed"; @Override public boolean evaluate(JSONObject jsonObject) { try { JSONArray nodeAspects = getNodeAspects(jsonObject); if (nodeAspects == null) { logger.info("No aspects found"); return false; } else { if (nodeAspects.contains(ASPECT_EMAILED)) { logger.info("Has been emailed"); return true; } else { logger.info("Has NOT been emailed"); return false; } } } catch (Exception err) { throw new AlfrescoRuntimeException("JSONException whilst running action evaluator: " + err.getMessage()); } }}This evaluator needs to be declared as a Spring bean too as follows:
<bean />An evaluator is used by referring to it via the Spring Bean ID, as in the following example when declaring a Document Library Action:
<action icon="email" type="javascript" label="actions.training.alfresco.sendAsEmail"> <param name="function">onActionFormDialog</param> <param name="itemKind">action</param> <param name="itemId">send-as-email</param> <param name="mode">create</param> <param name="destination">{node.nodeRef}</param> <param name="successMessage">message.send-as-email.success</param> <param name="failureMessage">message.send-as-email.failure</param> <evaluator negate="true">org.alfresco.training.evaluator.doclib.action.isEmailed</evaluator></action>Note here how you cannegate the outcome of the evaluation. Which means that in this case we want to show the Send As Email document library action in the UI if an email has not been sent.
tomcat/shared/classes/alfresco/web-extension/custom-slingshot-application-context.xml - the Spring Bean definition goes into this fileCustom evaluator implementations in Java does not lend themselves to be manually deployed into the application server.
Use a Share JAR SDK project instead.
aio/share-jar/src/main/resources/alfresco/web-extension/share-jar-slingshot-application-context.xml - the Spring Bean definition goes into this fileaio/share-jar/src/main/java/{custom package path} - the Java implementation of the evaluator goes into this directory