Visibility formulas let you keep your forms clean and relevant. Instead of showing every field to everyone, you can set a field to only appear when a certain selection is made. For example, a “Reason for repair” field can stay hidden until someone picks “Repair” from a drop-down list.
This article walks through the most common formulas, using the same field types and buttons you already see in FMX.
How to read a formula
Every formula points to a field and checks its value. In FMX, the field you reference goes inside {curly braces}. When the statement is true, the field appears; when it’s false, the field stays hidden.
| Symbol | What it means |
|---|---|
| { } | The custom field or resource you’re checking |
| == | “is equal to” |
| != | “is NOT equal to” |
| || | OR — either condition can be true |
| && | AND — both conditions must be true |
| includes( ) | Checks whether a selection contains a value |
Common formulas
When you need something to appear based on one selection
Use these when a field should appear after a single choice is made.
Checkbox — show the field when the box is checked:
Drop-down list — show the field when a specific option is chosen:
When something should appear even if multiple selections are made
For drop-down lists that allow more than one selection, use includes( ) to check whether a value is among the choices.
Either / or — appear when either option is selected:
Both required — appear only when both options are selected:
When a field should NOT show for a certain selection
Use != to hide a field when a particular resource is selected. This example hides the field whenever “Classroom” is the chosen resource:
"Classroom"), and match the spelling of your line items exactly — formulas are case-sensitive.Stuck on a complicated formula?
If you have a complicated visibility or value formula, let AI help. Open Google Gemini, paste in the [Copy AI Prompt] from your formula, and ask Gemini what specifications you need. It can help you check your logic and fill in the details.