Overriding ServiceNow Form View Inheritance - ben-vargas/servicenow-wiki GitHub Wiki

Form views in ServiceNow define how fields and layout elements are presented to users. By default, when navigating through referenced records, the current form view name is preserved, even if the referenced record’s table does not support that specific view. This view inheritance can lead to confusion and unnecessary complexity in managing views across different tables.

Understanding Form View Inheritance

When a user opens a record using a specialized view (e.g., "Emergency" for a Change Request), ServiceNow attempts to maintain that view name as the user follows reference links (such as the "Requested by" user field). If the target table doesn’t have a matching view, administrators may feel pressured to create corresponding views, resulting in cluttered view management and inconsistencies.

Key Challenges:

  • Unintended view carryover leads to missing fields or unexpected layouts.
  • Administrators may create unnecessary views just to align with inherited naming.
  • Over time, this complicates the user experience and increases administrative overhead.

Approaches to Override View Inheritance

1. View Rules

View Rules can specify conditions under which certain views are applied. While this method can enforce view consistency, it may be impractical if you must create multiple rules across many tables.

Pros: Granular control over which view appears.
Cons: Potentially numerous rules, which can be complex to maintain.

2. Client Script Override

A more direct and maintainable solution involves using a client script that resets or changes the inherited view. This prevents the undesired propagation of specialized views to unrelated tables.

Key Benefits:

  • Centralized logic that can handle multiple views at once.
  • Reduced need to create view rules or unnecessary views.
  • Easier maintenance and scalability.

Example: OnLoad Client Script to Override View Inheritance

Script Overview:

  • Checks if the current form’s sysparm_view matches a specific "old" view name.
  • If it does, replaces it with a default or desired "new" view (e.g., the standard view).
  • Adjusts related links so they no longer propagate the unwanted view name.
function onLoad() {
    // Override undesired inherited views on referenced records
    overrideViewInheritance('routineChange', '');
    overrideViewInheritance('emergencyChange', '');
}

function overrideViewInheritance(oldView, newView) {
    try {
        var sysparmViewElem = $('sysparm_view');
        if (sysparmViewElem && sysparmViewElem.value === oldView) {
            sysparmViewElem.value = newView;
        }

        // Update related lists and links
        var relatedListsWrapper = $('related_lists_wrapper');
        if (relatedListsWrapper) {
            relatedListsWrapper.select('a.linked').each(function(link) {
                link.href = link.href.gsub('sysparm_view=' + oldView, 'sysparm_view=' + newView);
            });
        }
    } catch (e) {
        console.error('Error overriding view inheritance:', e);
    }
}

Implementation Steps:

  1. Navigate to Client Scripts:
    Go to System Definition > Client Scripts.

  2. Create a New Client Script:

    • Name: Override View Inheritance
    • Table: Change Request [change_request] (or another appropriate table)
    • Type: OnLoad
    • Script: Paste the code above.

  3. Adjust Views as Needed:
    Update the overrideViewInheritance calls with the relevant old and new views for your scenario.

  4. Test in a Development Instance:
    Verify that the referenced records no longer inherit undesired views and that the user experience is improved.

Considerations

  • Limit Scope: Target specific tables and view names to avoid broad changes affecting unrelated records.
  • Testing & Validation: Always test in a sub-production environment before rolling out to production.
  • Documentation: Note all customizations in your system documentation to aid future maintenance.
  • Long-Term Maintenance: Periodically review this script and any view configurations to ensure they remain relevant over time and through upgrades.

Conclusion

By implementing a carefully crafted client script to override inherited form views, you can restore consistency and clarity to your forms. This approach reduces the overhead of managing multiple view rules or creating extraneous views, ultimately enhancing user experience and streamlining administrative tasks.