JIRA Multi select checkbox customfield not getting updated properly

Question

I have a transition screen from which I am getting values(s) via a checkbox control,  I need to get these values and update them on another checkbox control in the issues view screen. I tried the below code and it worked but it doesnt set the checkbox option as selected but just shows the value like a editable text but when I clicked edit that option is not selected.

def changeHolder = new DefaultIssueChangeHolder()
custField.updateValue(null, issue, new ModifiedValue(issue.getCustomFieldValue(custField), platvalue),changeHolder)

I read that you need to use options , so I used the below code but it doesnt work

def optionsManager = ComponentAccessor.getOptionsManager()

def config = platRelOnAPIField.getRelevantConfig(issue)

def options = optionsManager.getOptions(config)

log.debug("Options of Plat rel on field in API:"+options) // This prints properly

def newOption  = options.get(7) //I want to set to the 8th checkbox just for example,this value prints properly

ModifiedValue mVal = new ModifiedValue(issue.getCustomFieldValue(platRelOnAPIField),newOption);

platRelOnAPIField.updateValue(null, issue, mVal, new DefaultIssueChangeHolder());

But I end up with this exception

java.lang.ClassCastException: com.atlassian.jira.issue.customfields.option.LazyLoadedOption cannot be cast to java.util.Collection

I am a newbie to groovy/jira apis , so please can someone help me to set the checkbox value properly for the customfield

Ive checked this

https://community.atlassian.com/t5/Answers-Developer-Questions/Set-custom-field-select-list-value/qaq-p/491158

but I still get the same exception :(

Thanks !

Komail Badami · Answer

I managed to get this working with the below code ArrayList optionsList = new ArrayList(); FieldConfig fieldConfig = platRelOnAPIField.getRelevantConfig(issue); OptionsManager optionManager = ComponentAccessor.getOptionsManager(); platOptions = optionManager.getOptions(fieldConfig); for(def i = 0;i

Nic Brough -Adaptavist- · Answer

Ok, you'll have to go into quite a bit of debugging now.  I'm not sure what's wrong (unless the code you've not shown us here is somehow blanking out the field data you're trying to put into the change), but I'd check the values of variables on each line until you find out where the nulls/empty data is coming from.

Komail Badami · Answer

I checked for any error in the logs, there are no errors as such :(  Don't know where I am going wrong. The values are shown against the field but the checkboxes remain unchecked.

However, I find this line

[webpanels.children.condition.ChildIssuesPanelVisibilityCondition]Exception when evaluating if child issues panel should be displayed

But I dont think it has anything to do with my code