How to Create an Advanced Loop in the Legacy Builder

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Advanced Loops allow you to create a table within a table and capture more detailed information on list items from the first loop.

Advanced Loops

There are two main use cases for which the Advanced Loop comes in handy.

Nested Lists Conditional Screen for Loop Item

A primary list with an internal screen for additional details about items on the first loop.

An easy to visualize example is a moving company. When quoting a job, a mover would want to know how many rooms are in the house and the amount of furniture in each room. This is technically two lists where the second is dependent on the first. Without the first list, the furniture is not assigned to a room and without the second list, the movers won't know how many items are in a room. 

As each house is different, loops give the initial flexibility to add as many room as is needed for a specific house and the nested loop allows for each room to not only have furniture listed but details about those pieces provided as well. Movers may need to know the dimensions or weight of specific furniture and a nested loop is the only clean way to manage this entire example.

LB_Advanced Loop_Nested.png

Create an Advanced Loop

Using the moving company scenario, let's make a loop screen with a single nested loop. For more information on specifically creating Loop Screens, visit the Help Center article, "How to Repeat a Screen in the Legacy Builder."

  1. Once in the Form Builder, select + Add Screen in the Form Outline and add a drop down field to the screen called "Room."
  2. Hover over the new screen in the Form Outline and select the Loop icon.LB_Loop Icon.png
  3. On the Key Field select screen, toggle to the radio button for Use Existing Field and the drop down will default to the existing drop down field. Select Done to confirm.LB_Loop Screen_Use Existing Field.png
  4. In the Form Outline, the screen name will reflect the name of the key field but this can be edited to something more specific, i.e. "Rooms and Furniture List."
  5. Select the internal screen, currently labelled "New Screen #," and add another drop down field called "Furniture Piece" to the center workspace.
  6. Hover over that screen in the Form Outline and select the loop icon and select Use Existing Field again.
  7. Select the screen that is nested within "Furniture Piece" and give it a name, i.e. "Furniture Details."
  8. Add any fields that you would like to add further context to the furniture piece that has been selected within that room.

The mobile user will interact with the Advanced Loop similarly to how they interact with a regular loop, but they will complete all furniture pieces associated with a room before returning all the way back to the first screen to choose the next room.

Please Be Aware

Before implementing advanced loops in your form, please note that advanced loops are not compatible with the PDF Designer due to their complexity. If you already have a designed PDF, any existing loop converted to an advanced loop will no longer work. If you still need an advanced loop, either use the Standard PDF or contact our Client Engagement Services team to learn more about Custom PDF.

To learn more about GoCanvas Client Engagement Services, please contact your GoCanvas Customer Success Manager, Account Manager, Account Executive, or submit a ticket to support.

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  • Please add the ability to edit the Grid view for Loop screens.

    It would be very helpful to only display a few of a large number of possible fields on the screen. Also, the first key field is a fixed width that is extremely wide - this makes it hard to see the other fields at all on smaller devices, and difficult on larger screens.

  • Why would you change labels in the examples without clearly defining those changes in the step by step?  Makes the tutorial 10 times harder to follow.

  • It's been two years since you guys appear to have made any improvements.  I honestly don't understand why you haven't made it more intuitive... 

  • Is there a video for this?

  • Howdy Tayor,

    We do not currently have a tutorial video for this particular functionality. However, we are planning to make some improvements to this guide, including discussion of making a walkthrough video.

    If any updates are made, I will be sure to reply here so other users who have commented on/followed this Help Center topic will also be notified!

  • Is it possible to have selections made in the first looped screen carry forward to the next screen.  We have to capture multiple dimensions some of which are "standard" and will repeat.  If the selections carried forward we would only have to update the information that changed which would make measuring go much faster.

    As an example the location of a boor pull on a cabinet door will be the same for all cabinet doors in a kitchen generally.  Once the first one is measure every one after that should be the same.  the same goes for the location of hinges.  These dimensions might be different from one kitchen to the next but should be consistent within the same kitchen.  adding this information in over and over for each door is fairly time consuming.

  • door pull