Modified method is not triggering for Multi Select control in form Level in D365FO.

Hello everyone, I have received a requirement to add a multi-select control at the form level. However, after adding it, the Modified method is not triggering. 

I have added the control to the dialog form.

 

As per user selection I need to showcase those fields.

         To display specific fields based on user selection, I plan to write the code in the control's Modified event. However, the system is not triggering that method. To achieve this, I have followed the process below:

Lookup method in the form control.

public void lookup()
{
    MultiSelect multiSelectGrid = MultiSelect ::construct(Temp_Genders, Temp_Genders);

    Query query = new Query();
    QueryBuildDataSource queryBuildDataSource;
    queryBuildDataSource = query.addDataSource(tableNum(Temp));// My Table
    queryBuildDataSource.addSelectionField(fieldNum(Temp, Genders));

    multiSelectGrid.parmQuery(query);
    multiSelectGrid.parmCallingControl(this);
    multiSelectGrid.run();
}

• For a multi-select lookup, the 'SysLookupMultiSelectGrid' class needs to be used. 
• When the user selects values in the lookup, the 'SetSelected' method is triggered.
•  To achieve this, I have created a new class, extending from 'SysLookupMultiSelectGrid,' and overridden the necessary methods.

class MultiSelect extends SysLookupMultiSelectGrid
{
    #Characters
    public void setSelected()
    {
        dictfield          dictField;
        Common             currentDSRecord;
        FormDataSource     formdatasource;
        container          con = this.selectedStr;
        callingControlId.text(SysOperationHelper::convertMultiSelectedValueString(selectedId));

        formdatasource = callingControlId.dataSourceObject();
      
        FormRun  FormRunLoc= formdatasource.formRun();

        // My custom code
        if (formHasMethod(FormRunLoc,  identifierStr(visibilityValidation)))
        {
            FormRunLoc.visibilityValidation(con);
        }

        if(formdatasource && callingControlStr.dataField())
        {
            dictfield = new dictfield(formdatasource.table(),callingControlStr.dataField());
            currentDSRecord = formdatasource.cursor();
            currentDSRecord.(dictfield.id()) = currentDSRecord.(dictfield.id()) 
                            + SysOperationHelper::convertMultiSelectedValueString(selectedStr);
            callingControlStr.update();
        }
        else
        {
            callingControlStr.text(SysOperationHelper::convertMultiSelectedValueString(selectedStr));
        }
    }

    public static MultiSelect construct(FormControl ctrlId, FormControl ctrlStr)
    {
        MultiSelect lookupMS = new MultiSelect ();

        lookupMS.parmCallingControlId(_ctrlId);
        lookupMS.parmCallingControlStr(_ctrlStr);

        return lookupMS;
    }
}

From the above code, I am triggering the form method. That code you can find below.

Public TestForm extend FormRun
{
    public void visibilityValidation()
    {
        boolean     isMale, isFemale, isOthers;

	isMale   = conFind(_con, 'Male');
	isFemale = conFind(_con, 'Female');
	isOthers = conFind(_con, 'Others');
		
	if (conFind(_con, 'Both'))
	{
	    isMale = true;
	    isFemale = true;
	}

	Temp_Male.visible(isMale);
	Temp_Female.visible(isFemale);
	Temp_Others.visible(isOthers);
    }
}

If you have used "SysLookupMultiSelectCtrl" class. You can follow the above process.

Thank you, Yasin, For your support. 

Keep Daxing!!