You can find the Open a Subform action in the Subform Interaction group and the Open a Subview action in the Subview Interaction group.

Rule Breakdown
In this example, you have a form (Customer List Form) that shows a list of customers (Customer List view). You want to open the customer's details and order history as a subform after double-clicking a row. You add an action to the list-item double-click rule that opens the Customer Details and History Form, then configure the height and width of the subform.

This example has two forms: Customer List Form and Customer Details and History Form. The Customer List Form contains one view: Customer List. Because the list view is editable, there are a number of rules automatically added to the view that control the list behavior. For example, there is a rule for creating new list items and a rule for when you double-click a list item. The key point is there must be an event of some kind that starts the rule execution. Here, the event is double-clicking a list item, but you could also use another event such as a button click. After clicking the list item, the rule executes and opens the Customer Details and History Form as a subform.
Rules consist of events, conditions and actions. A valid rule contains at least one action.
- Events define when the rule should run, such as when a button is clicked, or when the form loads. (Events are optional, you can define "event-less" rules that you can call from other rules.)
- Conditions define whether the rule should run. If the criteria are true, continue the rule, and if the criteria are not met, stop the rule. For example, a condition might evaluate a form to confirm that required fields have content. (Conditions are optional - not all rules will require conditions.)
- Actions define what the rule should do. For example, show a message, start a workflow, or enable a form field. Rules can contain multiple actions that are run in sequence or in parallel.
Form
Follow the steps below to configure the Open a subform action.
- Edit the Customer List Form and open the Rules screen.

- Edit the Customer List (view) > When Customer List executed List item double click rule.

- With the Actions tab active, click Open a subform to add it to the rule definition pane. Click select Form, then navigate to and select Customer Details and History Form. Click (configure).

There are two sections to the Open a subform configuration screen: Subform Settings and Input Mappings. In the Subform Settings section, you can set the form's Title, Width, and Height properties. You can also use values from the Context Browser to dynamically set the properties at runtime.
The Subview Settings screen is the same as the Subform Settings screen.
The second tab on the Open a subform settings screen is Input Mappings (just right of the Subform Settings tab). Here, you can map properties from the parent form to the subform such as parameters, control values, and SmartObject values. This example does not cover Input Mappings.
- To set the width of the subform, enter a value into the Width text box. To set the height of the subform, enter a value into the Height text box. Click Finish to save the action configuration. Click OK to save the rule. Click Finish to save and exit the form.
The default dimensions of a subform are 80% height and 80% width of the parent form. Use whole numbers or pixel values between 70 and 32767 or percentages that do not exceed 100%. You can manually enter subform settings or use values from the Context Browser.
