Does @InvocationMethod accepts only 1 List<String> datataype parameter for Process Builder APEX call action?

Question

Is there any documentation available related to @InvocationMethod annotation of APEX (Spring 15 feature)? I've been going through the release notes -

http://releasenotes.docs.salesforce.com/spring15/spring15/release-notes/rn_forcecom_flow_apex.htm

http://releasenotes.docs.salesforce.com/spring15/spring15/release-notes/rn_apex_new_classes_methods.htm#invocablemethod

http://releasenotes.docs.salesforce.com/spring15/spring15/release-notes/rn_api_invocable_actions.htm#rn_api_invocable_actions

But to me it seems that we can pass Any Datatype into a method identified as @InvocationMethod, and it can accept Any number of parameters, but while I try to savea method with 2 parameters it returns following error:

Compile Error: Only one parameter is supported on invocable methods

Also, it only accepts List datatype parameter and only returns list type variable as well. is this a known Limitation or an Issue as well (and not documented anywhere) ?

Answer 1

While you can only pass one variable to @invocationmethod, you can use @invocablevariable in your custom class instead to permit multiple input variables from Process Builder.

Use the InvocableVariable annotation to identify variables used by invocable methods in custom classes.

The InvocableVariable annotation identifies a class variable used as an input or output parameter for an InvocableMethod method’s invocable action. If you create your own custom class to use as the input or output to an invocable method, you can annotate individual class member variables to make them available to the method.

Source: https://www.salesforce.com/us/developer/docs/apexcode/Content/apex_classes_annotation_InvocableVariable.htm

Answer 2

I think this could help us :) , new documentation:

• Only one method in a class can have the InvocableMethod annotation.
• Triggers can’t use invocable methods.
• The invocable method must be static and public or global, and its class must be an outer class.
• Other annotations can’t be used with the InvocableMethod annotation.
• There can be at most one input parameter and its data type must be one of the following:

  A list of a primitive data type or a list of lists of a primitive data type – the generic Object type is not supported. A list of an sObject type or a list of lists of an sObject type – the generic sObject type is not supported. A list of a user-defined type, containing variables of the supported types and with the InvocableVariable annotation. Create a custom global or public Apex class to implement your data type, and make sure your class contains at least one member variable with the invocable variable annotation.

• If the return type is not Null, the data type returned by the method must be one of the following: A list of a primitive data type or a list of lists of a primitive data type – the generic Object type is not supported. A list of an sObject type or a list of lists of an sObject type – the generic sObject type is not supported. A list of a user-defined type, containing variables of the supported types and with the InvocableVariable annotation. Create a custom global or public Apex class to implement your data type, and make sure your class contains at least one member variable with the invocable variable annotation.

You can use invocable methods in packages, but once you add an invocable method you can’t remove it from later versions of the package.

We can find here more help now: https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_classes_annotation_InvocableMethod.htm

(Still waiting to see why process builder allow us to set up more than one parameter though )

Thanks, Carolina.

Answer 3

Here's a simple example of using an inner class as described above.

public class HasInvocableMethodForFlow {

@InvocableMethod(label='What this method does' description='Use this in a flow passing single recordId in a collection.')
public static void MyInvMethod(recordInfo[] lstRecordInfo){
  
    //get the record ID
    recordInfo theRecord = lstRecordInfo.get(0);
    Id myRecordId = theRecord.recordId;
   
    //do stuff
        
}//MyInvMethod

public class recordInfo {
    @InvocableVariable
    public String recordId;
    
}//recordInfo 
}//HasInvocableMethodForFlow 

and the flow dialogue: