New to expressions and formulas? Try Expressions: The Essentials
New to column constraints? Try Column Constraints.
You can also learn more about other types of expressions.
Expressions in this article align with the Yes/No Expressions in Expression Builder in the app editor.
A Show_If column constraint is used when an input field should be shown or hidden depending on the values of one or more earlier field values in the form.
A Show_If constraint is a condition expression that determines if an input for this column should be shown in a form. This is usually based on the values of other columns. For example, the condition expression, [UserRating] = "5", will display the column only if the UserRating column value is "5". The condition expression, [Status] = "Green", will display the column if the Status column value is "Green".
The special column name, _THIS, is used to refer to the column being constrained. For example, a Show_If condition of ISBLANK([_THIS]) will show an input field only if the column value itself is blank. The column will be hidden once a data value has been entered and saved for the column.
Show_If conditions can also be defined on columns of type Show with a Category of Page Header to conditionally show or hide entire pages.
Show_If conditions can enabled for only form views or for the entire app. To control this behavior, see the Apply show-if constraints universally setting under UX > Options.