Value transfer to a new record from master detail relation

In some cases we need to transfer data from the referred record when creating a new record from a master-detail relation.

In the below example we have a class Project, that contains among others column Primary goal (primary_goal) and column Modified configuration items (modified-ci). These columns are highlighted together with a button for creating a new record in the master-detail relation in the below print screen.

Our goal is to open a new record of Task after clicking on he button New, which will refer to the given Project and will contain in columns Goal and Modified items values from the project - exactly as we see it in the below print screen.

There is entity-relationship diagram showing columns relevant for our example for more clarity:

To achieve this behaviour we will set up in the corresponding master-detail relation of the class Project a variable, that will be added to URL and that will be identified in the rule Before displaying a new record in the detail of the class Task.

We will set property Url variables for new record to "com=goal".

Rule of type Script of the event  Before displaying new record in detail:

var com = OG.QueryString.GetString('com');
var proId = OG.QueryString.GetInt('Fi1v');

if ( com == 'goal' && proId != null)
{
  var clPro = OGDataParent.Model.ClassDefs['project'];
  var drPro = OG.DataRow.GetDataById( clPro.Id, proId);

  if ( drPro != null)
  {
    //read Primary goal
    var id = drPro['primary_goal'];
    if ( id != null)
    {
      var clGoal = OGDataParent.Model.ClassDefs['goal'];
      OGActualDataRow['goal'] = OG.DataRow.GetDataById(clGoal.Id, id);
    }

    //read Modified configuration items
    var clCi = OGDataParent.Model.ClassDefs['ci'];
    var cis = drPro['modified-ci'];
    if ( cis != null && cis.Count > 0)
    {
      //OGActualDataRow['modified-ci'] = OG.DataRow.GetDataById(clCi.Id, cis[0].Id);

      OGActualDataRow['modified-ci'].AddRange(cis);
    }
  }
}