Rules are probably best described by using examples. This chapter contains numerous real world samples.

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Step 1 is named Expense Report, Step 2 is named Manager Approval and step 3 is named Accounting in the flow designer to match the sections in the parent form. The Manager role has been assigned to step 2 and the Accounting role has been assigned to step 3.

Here is an example of a rule that shows the Expense report details when the form loads, (the Manager Approval and Accounting sections are hidden) on step1, makes the Manager Approval section visible in the second step of the flow when performed by a manager and shows the Manager Approval and Accounting sections on step 3 when it is performed by an accounting department employee.

if (form.load) {
    var an = _data.getParameter("flow.activity.name");
    if (an === 'Manager Approval') {
        ManagerApproval.visible = true;
    }
    if (an === 'Accounting') {
        ManagerApproval.visible = true;
        Accounting.visible = true;
    }
}

Show/Hide Manager Approval on Step 2 and 3 of a flow

You have a flow and the first form has a Section for manager approval. The Section is hidden by default. Here is an example of a rule that makes the section visible in the second and third steps of the flow which are linked steps assigned to the manager and VP roles. 

if (form.load) {
  var an = _data.getParameter ("flow.activity.name");
  if (an === 'Manager' || an === 'VP'){
    ManagerApproval.visible = true;
  } else {
    ManagerApproval.visible = false;
  }
}

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You can build forms/flows In that meet Section 508 and WCAG 2.0 accessibility standards. Accessible forms/flows can assist users with visual and motor impairments. When the Accessible property is enabled for a form/flow, the error, "You can't leave this empty <control name>"  displays, if users move ahead from a required field without filling it. The status property for the empty control becomes invalid and sets the error message. Normally, the status property can be used in a business rule. For example, let's say a form has a text control named 't', and a message control named "m". If you write a rule to update the message field (control named m) with the STATUS of the required/invalid control (control named t), as shown below, it will not work because the "You can't leave this empty" message for a required control is not treated as it's status.

if(!t.valid)
  {
    m.value = t.status;
  }

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Selection controls' (radios, checkboxes, dropdowns, T/F) options can be set dynamically via rules rather than statically via the control's options property. However if the control comes from an XSD schema data source rather than one of the standard palette controls, then the designer must take care to not set the options to something outside of what is valid for that schema element. For example if your XSD has a string enumeration and list valid options as 'red', 'green', and 'blue', then you should not use a rule to dynamically set the options to 'small', 'medium', 'large'. If you do then then your form will not work correctly in use mode. If a user selects the option 'small' they will get a validation error on the form. This is because 'small' is not one of the options allowed by your underlying XSD schema.

Triggers & Dynamic Options

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You may want to calculate a date in a workflow based on a five day work week. This is a common business scenario and may be helpful if you are using the   Escalations feature. It is not possible to select calendar or working days for the Days interval of the Escalation feature at this time but this enhancement is planned for a future release. As a work-around, you can calculate X number of working days from the current date, and set that date in a Date control on your form. Then while configuring escalations, use the ‘Complete By’ condition and select the Date control.

Here is the business function/rule that will add 3 working days to the current date to give you the escalation date. Copy/paste the entire rule including the function in the Rule Editor. Substitute the name of your date control for <your date control>:

 function calcWorkingDays(fromDate, days) {
    var count = 0;
    while (count < days) {
        fromDate.setDate(fromDate.getDate() + 1);
      if (fromDate.getDay() !== 0 && fromDate.getDay() !== 6) {  // Skip weekends
            count++;
      }
    }
    return fromDate;
}
 
if (form.load && <your date control>.value.length === 0){
  var numWorkingDays = 3; 
  var today = frevvo.currentDate().split('-');
  var escDate = calcWorkingDays(new Date(today[0], today[1]-1, today[2]), numWorkingDays);
  var m = escDate.getMonth() + 1;
  var d = escDate.getDate();
  var y = escDate.getFullYear();
  <your date control>.value = m + '-' + d + '-' + y;
}

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if(count.value > 0){
  if(TableRepeat.maxOccurs < count.value)
    {
      TableRepeat.maxOccurs = count.value;
      TableRepeat.minOccurs = count.value;
      Repeat.maxOccurs = count.value;
      Repeat.minOccurs = count.value;
    }
 
  else{
    TableRepeat.minOccurs = count.value;
    TableRepeat.maxOccurs = count.value;
    Repeat.minOccurs = count.value;
    Repeat.maxOccurs = count.value;
      
  }
}

Notice the rule flips the order of minOccurs and maxOccurs in the if and else blocks so that at a given point minOccurs is not set to something greater than maxOccurs and maxOccurs is not set to something less than minOccurs.

For example, when you set the count to 6, the rule executes and sets minOccurs and maxOccurs values to 6. Now if you change the count to 3, then you will have to first set minOccurs to 3 (because it should never be greater than maxOccurs), and then change the maxOccurs to 3. Then if you change the count to 8, you have to first set maxOccurs to 8 (because it should never be less than minOccurs), and then set minOccurs to 8.

Entering "5" as the number of travelers, sets the minOccurs and maxOccurs to 5 and shows 5 information sections and 5 rows in the table. Note the  plus and  minus icons are not visible preventing users from adding or removing repeat items or table rows,

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A rule can dynamically display an image uploaded to your form via the upload control. In this example the upload control is named 'u'. The form also must contain a message control as a place holder for displaying the uploaded image. The rule dynamically creates a URL to the uploaded image in the temporary attachment repository. The upload control's value 'u.value' is a GUID that uniquely identifies the attachment. The uploaded image will be included in the submission PDF.

if (u.value.length > 0) {
  var baseUrl = "/frevvo/web/tn/" +
      _data.getParameter('tn.id') +
      "/user/"+_data.getParameter('user.id') +
      "/app/"+_data.getParameter('app.id') +
      "/form/"+_data.getParameter('form.id');
 
  im.value = '<img src="' +
         baseUrl + '/attachment/' + u.value+'/does_not_matter"/>';
}

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