field.updateValue method explanation

[Aishwarya Rajan]

May I know 

field.updateValue(null, currentIssue, new ModifiedValue(issue.getCustomFieldValue(field), parentMyFieldValue),changeHolder);

what does tghe null in the argument indicate here?

I am aware that  currentIssue means the Issue whose value need to be changed ACCORDING TO THE PARENT ISSUE FIELD and ModifiedValue method sets child field value to value present in parent field.  But, not sure why that null is used.

[Aishwarya Rajan]

Joshua Yamdogo @ Adaptavist Hi Joshua..I have a situation wherein I have to copy a custom field checkbox value of parent epic issue to custom file checkbox field of child story.

import com.atlassian.jira.component.ComponentAccessor
import com.atlassian.jira.issue.Issue
import com.atlassian.jira.issue.util.DefaultIssueChangeHolder
import com.atlassian.jira.issue.ModifiedValue

def field = ComponentAccessor.getCustomFieldManager().getCustomFieldObject('customfield_10434')

Issue currentIssue = getIssueContext() as Issue

def parentFieldValue = currentIssue.parentObject.getCustomFieldValue(field)

def changeHolder = new DefaultIssueChangeHolder();

def currentIssueStatus = currentIssue.getStatus().getName()

if(currentIssueStatus=="Open"){
field.updateValue(null, currentIssue, new ModifiedValue(currentIssue.getCustomFieldValue(field), parentFieldValue),changeHolder);
}

I tried the above code but its not working...can anyone help me with this?? Any leads appreciated!

[Joshua Yamdogo @ Adaptavist]

Where is this script being used? Post-function?

[Joshua Yamdogo @ Adaptavist]

You can read more about the updateValue() method here:

https://docs.atlassian.com/software/jira/docs/api/7.8.0/com/atlassian/jira/issue/fields/OrderableField.html#updateValue-com.atlassian.jira.issue.fields.layout.field.FieldLayoutItem-com.atlassian.jira.issue.Issue-com.atlassian.jira.issue.ModifiedValue-com.atlassian.jira.issue.util.IssueChangeHolder-

The first parameter is for the FieldLayoutItem variable. https://docs.atlassian.com/software/jira/docs/api/7.8.0/com/atlassian/jira/issue/fields/layout/field/FieldLayoutItem.html

Null gets passed in when you don't have any FieldLayoutItem variable.