Unique Select Options Per Repeat Entry Using List Value Transform

This guide explains how to use the “List Value Transform”, “Repeat Field Value Aggregator”, and “Hidden” fields together to ensure that each entry inside a “Repeat Group” only shows Select options that have not already been chosen in another entry. The “Repeat Field Value Aggregator” field collects all values currently selected across every repeat entry and combines them into a single list. The “List Value Transform” then uses that list to remove already-selected options from the Select field, so each new entry only shows what is still available.

1. INITIAL SETUP:

• Drag and drop a “Repeat” field onto your form. Then, place a “Select” field inside the “Repeat” field by dragging and dropping it within the Repeat section.
• Rename the fields as needed.

• Drag and drop a “List Value Transform”, a “Hidden” and a “Repeat Field Value Aggregator” field onto your form.
• Rename the fields as needed.

2. CONFIGURE THE "SELECT" FIELD (INSIDE THE REPEAT GROUP):

• Click the pencil icon on the “Select” field inside the Repeat Group.
• Select Options:
• Enter your full list of items, one per line. For example:

Monitor

Pump

Valve

Sensor

Filter

• This is the initial list displayed when the form first loads. The “List Value Transform” field will update this list dynamically at runtime to remove already-chosen values.

3. CONFIGURE THE "HIDDEN" FIELD:

• Click the pencil icon on the “Hidden” field.
• Value:
• Enter your complete master list of selectable values as a comma-separated string. For example: Monitor,Pump,Valve,Sensor,Filter.
• This field acts as the permanent source of truth, the full list of all possible options. It is referenced by the “List Value Transform” as List A (the starting set). It should never be modified by the user.

4. CONFIGURE THE "REPEAT FIELD VALUE AGGREGATOR" FIELD:

• Click the pencil icon on the “Repeat Field Value Aggregator” field.
• Field to Aggregate:
• Select the “Select” field inside the Repeat Group.
• This tells the aggregator which field's values to collect and combine across all repeat entries.

• Delimiter:
• Set to , (comma).
• Defines how the collected values are joined into a single string (e.g. Monitor,Valve).

• Show Aggregate Value:
• Enable this option.

5. CONFIGURE THE "LIST VALUE TRANSFORM" FIELD:

• Click the pencil icon on the “List Value Transform” field.
• List A Field ID:
• Set the field ID of the “Hidden” field.
• Here we are using: 9422-d85a-2d9e

• List A Source:
• Set to value.
• Reads the value stored in the “Hidden” field.

• List A Delimiter:
• Set to , (comma).
• Tells the field how the items in List A are separated.

• List B Field ID:
• Set the field ID of the “Repeat Field Value Aggregator” field.
• Here we are using: 5d15-a5ac-9020

• List B Source:
• Set to value.
• Reads the current output of the aggregator.

• List B Delimiter:
• Set to , (comma).
• Tells the field how the items in List B are separated.

• Operation:
• Set to subtract (A minus B).
• Removes all items found in List B from List A, leaving only the options not yet selected.

• Output Field:
• Set the field ID of the “Select” field (inside the Repeat Group).
• Here we are using: 59ba-9226-087f

• Output Field Attribute:
• Set to select_options.
• Targets the options list of the Select field specifically.

• Run on Page Load:
• Enable this option.
• Ensures the available options are refreshed each time a new repeat entry is added or the form loads.

• Show Result Value:
• Enable this option.
• Makes the result visible for reference and troubleshooting.

6. TEST THE FORM:

• Try the form and add a new repeat entry.

• Select an item (e.g. Monitor) from the Select field in the first entry.

• Click “Add” to create a second repeat entry.
• Check the “Repeat Field Value Aggregator” field, it should now show Monitor as its aggregated value.

• Open the Select field in the second entry. Monitor should no longer appear in the list, as the “List Value Transform” has subtracted it using the aggregator's output.

• Continue adding entries and verify that each time a new value is selected, the “Repeat Field Value Aggregator” updates accordingly, and the remaining options in the next entry shrink to exclude all previously chosen values.

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