code: public <E> void addComboField(String fieldLabel, ComboBoxModel<E> comboBoxModel, boolean editable) {
  		validateNotTabbed();
  		JComboBox<E> field = new JComboBox<>(comboBoxModel);
  		field.setEditable(editable);
  		this.addField(fieldLabel, field, field, 0.0D);
  	}
docs: Adds a combo box field, possibly editable, with the given label and model.
  <p>
  Control of selection state (i.e. set/get selected item) is done through the combo box model.
  
  @param <E> the type of the elements of the combo box model.
  @param fieldLabel the name of the label of the combo box field.
  @param comboBoxModel the model to set into the combo box.
  @param editable {@code true} if the combo box should be editable, {@code false} otherwise.
  @throws IllegalArgumentException if any of the following conditions is true:
  <ul>
  <li>the dialogue has tabs;</li>
  <li>a field with the given label already exists.</li>
  </ul>
  @since 2.6.0
  @see #addComboField(String, ComboBoxModel)
  @see #addComboField(int, String, ComboBoxModel, boolean)
  @see #setComboBoxModel(String, ComboBoxModel)