Guide users step by step
Good screen flows ask only what is needed, validate early, create records at the end with error handling, and use custom components when standard ones are not enough.
- DesignScreens, decisions and confirmation.
- ComponentsStandard, reactive and custom LWC.
- LaunchingQuick actions, record pages and sites.
Screen flows turn complex processes into guided steps for users and customers — onboarding, case intake, quotes. Interviewers check that you can design clear screens, validate input, and extend flows with custom components when needed.
1. How would you design a screen flow for creating a support case?
Case intake screen flow
- Screen 1Choose product and issue type (record choice set)
- DecisionBilling or technical?
- Screen 2Relevant questions only, with validation
- Create RecordsCase linked to the contact; fault path for errors
- ConfirmationShow the case number and next steps
2. Which screen components should you know?
Text and number inputs, picklists, radio buttons and checkbox groups (with choice sets), lookup, date, file upload, display text, address, name, email, phone, data table (select records), repeater (add several rows of the same fields), and sections with columns for layout. Custom LWC components can be added for anything else.
3. What are reactive screen components?
Components on the same screen that update immediately when another component changes — for example showing a calculated total as the user types quantities, or filtering a data table by a picklist — without moving to the next screen.
4. How do you validate input on a screen?
Use component-level validation (a formula that must be true, with an error message), required settings, and for custom LWC components the @api validate() method. For business rules across fields, use a Decision after the screen to loop back with a message.
/* Component validation: email must end with the company domain */
ENDS({!Email}, "@learnfrenzy.com")5. How do you use a Lightning Web Component inside a screen flow?
Add the lightning__FlowScreen target in the component's meta XML, expose input and output properties with @api and design properties, notify the flow of changes with FlowAttributeChangeEvent, and implement validate() to block navigation when invalid.
6. How do you launch a screen flow from a record?
Create a quick action of type Flow on the object (the record Id is passed into an input variable named recordId), or place the Flow component on the Lightning record page with the record Id mapped. Users can also run flows from the utility bar or a button.
7. How do you let a flow user go back without losing data?
Enable the Previous button on screens; values entered are kept. Be careful with elements that create records between screens — design so records are created at the end, or handle going back explicitly.
8. How do you use screen flows for customers on Experience Cloud?
Add the flow to an Experience Cloud page, set it to run in the right user context, give guest or community users access to the flow and objects securely (sharing sets, guest user sharing rules), and keep record access minimal.
Remember
Key points
- recordId input variable
Auto-filled from quick actions.
- Validate on the screen
Formula validation and validate().
- Create records at the end
Avoid half-finished data.
- Fault paths for errors
Show users a clear message.
Interview drill
Follow-up questions
What the interviewer asks after your first answer. Turn on practice mode, answer each one aloud, then reveal.
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1 What is a record choice set? Basic
A choice source that queries records (for example active Products) to populate a picklist or radio buttons on a screen.
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2 How do you show a list of records for the user to select? Basic
Use the Data Table screen component with a record collection; selected rows are available as output.
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3 What is the Repeater component? Intermediate
A screen component that lets users add multiple sets of the same fields, such as several family members, producing a collection.
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4 How do you make a field appear only for certain answers? Basic
Set component visibility conditions based on other screen values.
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5 Can a screen flow run without a user being logged in? Advanced
Yes, on an Experience Cloud site for guest users, with strict guest user permissions and system-context design reviewed for security.
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6 How do you pass values from a flow back to the page? Intermediate
Use output variables; when embedded in an LWC with lightning-flow, handle the onstatuschange event to read outputs.