ScriptRunner for Jira Cloud plus its companion app, Behaviors, support the ability to hide/show fields in Cloud: https://marketplace.atlassian.com/apps/1228522/behaviours-scriptrunner-for-jira-cloud?tab=overview&hosting=cloud

And the apps suggested do not support all type of custom fields 

This is a useful feature, it is a shame that Jira is refusing to implement it.

Hi,

Its really disappointing to see that you waited for votes to be collected only to then reject what people really want?

Also none of the workarounds really work for the cloud version.

Can someone please suggest on how to get this working if I am using Jira cloud and want to dynamically hide/show fields on customer form using Jira service desk.

Hi,

i'd like to add that only this week I've found a proper solution for that, which we've had available all along.

I'm now using Behaviours, which is part of ScriptRunner to show or hide 2 insight custom fields 'Cost Centers' and 'Companies' on a Service Desk request type.

https://scriptrunner.adaptavist.com/4.3.1/jira/behaviours-overview.html

This actually hides or shows fields while the ticket is created on the Service Desk portal, it also offers this at a later (edit) point i believe.

import com.onresolve.jira.groovy.user.FieldBehaviours
import groovy.transform.BaseScript@BaseScript FieldBehaviours fieldBehaviours

def CostCenterFieldID = getFieldByName("Cost Centers")
def CompanyFieldID = getFieldByName("Companies")

if (getFieldById(getFieldChanged()).getValue() == "KAM-150") {CostCenterFieldID.setHidden(false)
CostCenterFieldID.setRequired(false)
CompanyFieldID.setHidden(false)
CompanyFieldID.setRequired(false)
}
else {
CostCenterFieldID.setHidden(true)
CostCenterFieldID.setRequired(false)
CompanyFieldID.setHidden(true)
CompanyFieldID.setRequired(false)
}

Hope this can help someone

BR

Hi everyone,

Thank you for your interest in this issue.

While this suggestion has gathered significant interest, we're unable to implement all of the excellent suggestions you make. We don't plan to work on this for the foreseeable future. This suggestion will be reviewed in about 12 months time, at which point we’ll consider whether we need to alter its status. 

There is a workaround mentioned in the description.

Also, there are several third party add-ons that solve many of the use cases mentioned here:

• Jirassimo Intake Forms for Jira
• Dynamic Forms for Jira
• Power Custom Fields PRO - Custom Fields
• Live SQL Custom Fields
• Dynamic Forms for Cascading Select

We understand this decision will be disappointing to everyone who voted for this issue. While we believe this suggestion would improve the product, after careful review of the most pressing needs of our customers, and especially since third party add-ons are available, we've decided to prioritize other areas of the Jira Server roadmap, including:

• Performance and stability improvements
• Archiving projects for improved performance
• Optimising the use of custom fields
• Improving performance of boards
• Improving Jira notifications
• Allowing users to edit shared filters and dashboards
• Mobile app for Jira Server

We hope that you appreciate our candid and transparent communication. You can learn more about our approach to highly voted server suggestions here.

To learn more on how your suggestions are reviewed, see our updated workflow for server feature suggestions.

Kind regards,
Jira Server Product Management

We actually use one add-on (in JIRA Cloud) which provides us with the functionality to have the rules like that between the fields, Jirassimo Intake Forms for JIRA
True that those are not native JIRA issue forms, but works for our use-cases so far

+1 this is a good idea

There is such a lack of add-ons available for the JIRA Cloud.  I simply need to make one field required depending on the selection of another custom field.  Ex: if user selects the "request type" is a "large" effort, then force another field to be required.

Atlassian, please add this functionality to JIRA Cloud.

I wonder why Atlassian is not rolling out this feature from 2014!!