Passing data from a task into the app form

Demonstrates how to pass data into an application form via tasks

This guide explains how to pass data from a task into the action application form.

Prerequisites

Scenario

Let’s look deeper at the scenario from the Complex Tasks Tutorial where we have an ANC follow-up task which recurs eight times, and we want to ask the user different questions on the first and last follow-up.

Developing the task

From the Complex Tasks Tutorial, here is the task.

const { DateTime } = require('luxon');

module.exports = {
  name: 'pnc-after-pregnancy',
  icon: 'icon-follow-up',
  title: 'task.pnc_followup',
  appliesTo: 'contacts',
  appliesToType: ['patient'],
  appliesIf: function (contact) {
    const userIsChw = user.parent && user.parent.contact_type === 'chw_area';
    const isDead = contact.contact.date_of_death;
    const isMuted = contact.contact.muted;

    if (userIsChw && !isDead && !isMuted) {
      const mostRecentPregnancy = Utils.getMostRecentReport(contact.reports, 'pregnancy');
      const calculatedLmp = mostRecentPregnancy && Utils.getField(mostRecentPregnancy, 'g_details.estimated_lmp');
      this.lmp = calculatedLmp && DateTime.fromFormat(calculatedLmp, 'yyyy-MM-dd');
      
      return this.lmp && this.lmp.isValid;
    }
  },
  events: [12, 20, 26, 30, 34, 36, 38, 40] // follow-up weeks after LMP
    .map(weekAfterLmp => ({
      id: `pnc-week-${weekAfterLmp}`,
      start: weekAfterLmp > 30 ? 6 : 7,
      end: weekAfterLmp > 30 ? 7 : 14,
      dueDate: function () {
        return this.lmp.plus({ weeks: weekAfterLmp }).toJsDate();
      }
    })),
  resolvedIf: function (contact, report, event, dueDate) {
    const start = Utils.addDate(dueDate, -event.start).getTime();
    const end = Utils.addDate(dueDate, event.end + 1).getTime();
    const pncInWindow = Utils.isFormSubmittedInWindow(contact.reports, 'pnc_followup', start, end);
    const assessmentInWindow = Utils.isFormSubmittedInWindow(contact.reports, 'assessment_followup', start, end);
    return pncInWindow || assessmentInWindow;
  },
  actions: [{
    form: 'pnc_followup',
    modifyContent: function (content, contact, report, event) {
      const followupCount = this.definition.events.findIndex(e => event.id === e.id) + 1;
      content.t_followup_count = followupCount.toString();
    }
  }]
};

modifyContent

Let’s take a look at the actions section and specifically the modifyContent attribute. This modifyContent attribute allows the task to pass data from the task (in JavaScript) into the action app form (xlsx). The content object is the object which binds to the inputs section in the app form. You can pass data into the app form by assigning values onto this object.

This function calculates t_followup_count to be the index of the event which is being completed. So the first task event (which appears after 12 weeks) is followup 1, and the task event after 34 weeks is followup 5.

The action form

In this sample app form survey, the value of t_followup_count is listed in the inputs section and the CHT binds the data passed by the task onto this hidden variable. An example calculation is_first_followup demonstrates how to use the value in the form’s logic. is_first_followup will be true 12 weeks after the LMP date, and false on all other followups.

typenamelabelrequiredrelevantappearanceconstraintconstraint_messagecalculation
begin groupinputsfield-list
hiddent_followup_countData from task
end group
calculateis_first_followupif(${t_follow_up_count}=‘1’,true,false)

Related Content

CHT Applications > Tutorials > Complex Tasks

Building a more complex task

CHT Applications > Tutorials > App Forms

Building CHT app forms

CHT Applications > Reference > tasks.js

Tasks: Definition of tasks shown to app users

CHT Applications > Quick Guides > Forms > Form Inputs

Data accessible from within CHT forms


Last modified 06.04.2023: 1008 - Fix Partials (#1009) (4938b3e0)
Edit this page Create documentation issue Create project issue