private void addExtraEffortCell(Listitem item,
EffortDurationPicker extraDurationPicker, Checkbox checkbox) {
Listcell extraEffortCell = new Listcell();
Hbox hbox = new Hbox();
hbox.setSclass("extra effort cell");
hbox.appendChild(extraDurationPicker);
hbox.appendChild(checkbox);
extraEffortCell.appendChild(hbox);
item.appendChild(extraEffortCell);
}