ComboBoxListCell (JavaFX 13)

Module javafx.controls
Package javafx.scene.control.cell

## Class ComboBoxListCell<T>

- java.lang.Object
- - javafx.scene.Node
  - - javafx.scene.Parent
    - - javafx.scene.layout.Region
      - - javafx.scene.control.Control
        - - javafx.scene.control.Labeled
          - - javafx.scene.control.Cell<T>
            - - javafx.scene.control.IndexedCell<T>
              - - javafx.scene.control.ListCell<T>
                - - javafx.scene.control.cell.ComboBoxListCell<T>

- Type Parameters:
    `T` - The type of the elements contained within the ListView.
  All Implemented Interfaces:
    `Styleable`, `EventTarget`, `Skinnable`

      public class ComboBoxListCell<T>
      extends ListCell<T>

  A class containing a `ListCell` implementation that draws a `ComboBox` node inside the cell.

  By default, the ComboBoxListCell is rendered as a `Label` when not being edited, and as a ComboBox when in editing mode. The ComboBox will, by default, stretch to fill the entire list cell.

  To create a ComboBoxListCell, it is necessary to provide zero or more items that will be shown to the user when the `ComboBox` menu is showing. These items must be of the same type as the ListView items sequence, such that upon selection, they replace the existing value in the `items` list.

  Since:
    JavaFX 2.2

- - ### Property Summary

    Properties
    Type | Property | Description
    --- | --- | ---
    `BooleanProperty` | `comboBoxEditable` | A property representing whether the ComboBox, when shown to the user, is editable or not.
    `ObjectProperty<StringConverter<T>>` | `converter` | The `StringConverter` property.

    - ### Properties inherited from class javafx.scene.control.ListCell

      `listView`

    - ### Properties inherited from class javafx.scene.control.IndexedCell

      `index`

    - ### Properties inherited from class javafx.scene.control.Cell

      `editable, editing, empty, item, selected`

    - ### Properties inherited from class javafx.scene.control.Labeled

      `alignment, contentDisplay, ellipsisString, font, graphic, graphicTextGap, labelPadding, lineSpacing, mnemonicParsing, textAlignment, textFill, textOverrun, text, underline, wrapText`

    - ### Properties inherited from class javafx.scene.control.Control

      `contextMenu, skin, tooltip`

    - ### Properties inherited from class javafx.scene.layout.Region

      `background, border, cacheShape, centerShape, height, insets, maxHeight, maxWidth, minHeight, minWidth, opaqueInsets, padding, prefHeight, prefWidth, scaleShape, shape, snapToPixel, width`

    - ### Properties inherited from class javafx.scene.Parent

      `needsLayout`

    - ### Properties inherited from class javafx.scene.Node

      `accessibleHelp, accessibleRoleDescription, accessibleRole, accessibleText, blendMode, boundsInLocal, boundsInParent, cacheHint, cache, clip, cursor, depthTest, disabled, disable, effectiveNodeOrientation, effect, eventDispatcher, focused, focusTraversable, hover, id, inputMethodRequests, layoutBounds, layoutX, layoutY, localToParentTransform, localToSceneTransform, managed, mouseTransparent, nodeOrientation, onContextMenuRequested, onDragDetected, onDragDone, onDragDropped, onDragEntered, onDragExited, onDragOver, onInputMethodTextChanged, onKeyPressed, onKeyReleased, onKeyTyped, onMouseClicked, onMouseDragEntered, onMouseDragExited, onMouseDragged, onMouseDragOver, onMouseDragReleased, onMouseEntered, onMouseExited, onMouseMoved, onMousePressed, onMouseReleased, onRotate, onRotationFinished, onRotationStarted, onScrollFinished, onScroll, onScrollStarted, onSwipeDown, onSwipeLeft, onSwipeRight, onSwipeUp, onTouchMoved, onTouchPressed, onTouchReleased, onTouchStationary, onZoomFinished, onZoom, onZoomStarted, opacity, parent, pickOnBounds, pressed, rotate, rotationAxis, scaleX, scaleY, scaleZ, scene, style, translateX, translateY, translateZ, viewOrder, visible`

  - ### Field Summary

    - ### Fields inherited from class javafx.scene.layout.Region

      `USE_COMPUTED_SIZE, USE_PREF_SIZE`

    - ### Fields inherited from class javafx.scene.Node

      `BASELINE_OFFSET_SAME_AS_HEIGHT`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `ComboBoxListCell()` | Creates a default ComboBoxListCell with an empty items list.
    `ComboBoxListCell​(ObservableList<T> items)` | Creates a default `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown.
    `ComboBoxListCell​(StringConverter<T> converter, ObservableList<T> items)` | Creates a `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown, and the `StringConverter` being used to convert the item in to a user-readable form.
    `ComboBoxListCell​(StringConverter<T> converter, T... items)` | Creates a `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown, and the `StringConverter` being used to convert the item in to a user-readable form.
    `ComboBoxListCell​(T... items)` | Creates a default `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown.

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `cancelEdit()` | Call this function to transition from an editing state into a non-editing state, without saving any user input.
    `BooleanProperty` | `comboBoxEditableProperty()` | A property representing whether the ComboBox, when shown to the user, is editable or not.
    `ObjectProperty<StringConverter<T>>` | `converterProperty()` | The `StringConverter` property.
    `static <T> Callback<ListView<T>,​ListCell<T>>` | `forListView​(ObservableList<T> items)` | Creates a ComboBox cell factory for use in `ListView` controls.
    `static <T> Callback<ListView<T>,​ListCell<T>>` | `forListView​(StringConverter<T> converter, ObservableList<T> items)` | Creates a ComboBox cell factory for use in `ListView` controls.
    `static <T> Callback<ListView<T>,​ListCell<T>>` | `forListView​(StringConverter<T> converter, T... items)` | Creates a ComboBox cell factory for use in `ListView` controls.
    `static <T> Callback<ListView<T>,​ListCell<T>>` | `forListView​(T... items)` | Creates a ComboBox cell factory for use in `ListView` controls.
    `StringConverter<T>` | `getConverter()` | Returns the `StringConverter` used in this cell.
    `ObservableList<T>` | `getItems()` | Returns the items to be displayed in the ChoiceBox when it is showing.
    `boolean` | `isComboBoxEditable()` | Returns true if the ComboBox is editable.
    `void` | `setComboBoxEditable​(boolean value)` | Configures the ComboBox to be editable (to allow user input outside of the options provide in the dropdown list).
    `void` | `setConverter​(StringConverter<T> value)` | Sets the `StringConverter` to be used in this cell.
    `void` | `startEdit()` | Call this function to transition from a non-editing state into an editing state, if the cell is editable.
    `void` | `updateItem​(T item, boolean empty)` | The updateItem method should not be called by developers, but it is the best method for developers to override to allow for them to customise the visuals of the cell.

    - ### Methods inherited from class javafx.scene.control.ListCell

      `commitEdit, createDefaultSkin, executeAccessibleAction, getListView, listViewProperty, queryAccessibleAttribute, updateListView`

    - ### Methods inherited from class javafx.scene.control.IndexedCell

      `getIndex, indexProperty, updateIndex`

    - ### Methods inherited from class javafx.scene.control.Cell

      `editableProperty, editingProperty, emptyProperty, getInitialFocusTraversable, getItem, isEditable, isEditing, isEmpty, isItemChanged, isSelected, itemProperty, layoutChildren, selectedProperty, setEditable, setItem, updateSelected`

    - ### Methods inherited from class javafx.scene.control.Labeled

      `alignmentProperty, contentDisplayProperty, ellipsisStringProperty, fontProperty, getAlignment, getClassCssMetaData, getContentBias, getContentDisplay, getControlCssMetaData, getEllipsisString, getFont, getGraphic, getGraphicTextGap, getInitialAlignment, getLabelPadding, getLineSpacing, getText, getTextAlignment, getTextFill, getTextOverrun, graphicProperty, graphicTextGapProperty, isMnemonicParsing, isUnderline, isWrapText, labelPaddingProperty, lineSpacingProperty, mnemonicParsingProperty, setAlignment, setContentDisplay, setEllipsisString, setFont, setGraphic, setGraphicTextGap, setLineSpacing, setMnemonicParsing, setText, setTextAlignment, setTextFill, setTextOverrun, setUnderline, setWrapText, textAlignmentProperty, textFillProperty, textOverrunProperty, textProperty, toString, underlineProperty, wrapTextProperty`

    - ### Methods inherited from class javafx.scene.control.Control

      `computeMaxHeight, computeMaxWidth, computeMinHeight, computeMinWidth, computePrefHeight, computePrefWidth, contextMenuProperty, getBaselineOffset, getContextMenu, getCssMetaData, getSkin, getTooltip, isResizable, setContextMenu, setSkin, setTooltip, skinProperty, tooltipProperty`

    - ### Methods inherited from class javafx.scene.layout.Region

      `backgroundProperty, borderProperty, cacheShapeProperty, centerShapeProperty, getBackground, getBorder, getHeight, getInsets, getMaxHeight, getMaxWidth, getMinHeight, getMinWidth, getOpaqueInsets, getPadding, getPrefHeight, getPrefWidth, getShape, getUserAgentStylesheet, getWidth, heightProperty, insetsProperty, isCacheShape, isCenterShape, isScaleShape, isSnapToPixel, layoutInArea, layoutInArea, layoutInArea, layoutInArea, maxHeight, maxHeightProperty, maxWidth, maxWidthProperty, minHeight, minHeightProperty, minWidth, minWidthProperty, opaqueInsetsProperty, paddingProperty, positionInArea, positionInArea, prefHeight, prefHeightProperty, prefWidth, prefWidthProperty, resize, scaleShapeProperty, setBackground, setBorder, setCacheShape, setCenterShape, setHeight, setMaxHeight, setMaxSize, setMaxWidth, setMinHeight, setMinSize, setMinWidth, setOpaqueInsets, setPadding, setPrefHeight, setPrefSize, setPrefWidth, setScaleShape, setShape, setSnapToPixel, setWidth, shapeProperty, snappedBottomInset, snappedLeftInset, snappedRightInset, snappedTopInset, snapPosition, snapPositionX, snapPositionY, snapSize, snapSizeX, snapSizeY, snapSpace, snapSpaceX, snapSpaceY, snapToPixelProperty, widthProperty`

    - ### Methods inherited from class javafx.scene.Parent

      `getChildren, getChildrenUnmodifiable, getManagedChildren, getStylesheets, isNeedsLayout, layout, lookup, needsLayoutProperty, requestLayout, requestParentLayout, setNeedsLayout, updateBounds`

    - ### Methods inherited from class javafx.scene.Node

      `accessibleHelpProperty, accessibleRoleDescriptionProperty, accessibleRoleProperty, accessibleTextProperty, addEventFilter, addEventHandler, applyCss, autosize, blendModeProperty, boundsInLocalProperty, boundsInParentProperty, buildEventDispatchChain, cacheHintProperty, cacheProperty, clipProperty, computeAreaInScreen, contains, contains, cursorProperty, depthTestProperty, disabledProperty, disableProperty, effectiveNodeOrientationProperty, effectProperty, eventDispatcherProperty, fireEvent, focusedProperty, focusTraversableProperty, getAccessibleHelp, getAccessibleRole, getAccessibleRoleDescription, getAccessibleText, getBlendMode, getBoundsInLocal, getBoundsInParent, getCacheHint, getClip, getCursor, getDepthTest, getEffect, getEffectiveNodeOrientation, getEventDispatcher, getId, getInitialCursor, getInputMethodRequests, getLayoutBounds, getLayoutX, getLayoutY, getLocalToParentTransform, getLocalToSceneTransform, getNodeOrientation, getOnContextMenuRequested, getOnDragDetected, getOnDragDone, getOnDragDropped, getOnDragEntered, getOnDragExited, getOnDragOver, getOnInputMethodTextChanged, getOnKeyPressed, getOnKeyReleased, getOnKeyTyped, getOnMouseClicked, getOnMouseDragEntered, getOnMouseDragExited, getOnMouseDragged, getOnMouseDragOver, getOnMouseDragReleased, getOnMouseEntered, getOnMouseExited, getOnMouseMoved, getOnMousePressed, getOnMouseReleased, getOnRotate, getOnRotationFinished, getOnRotationStarted, getOnScroll, getOnScrollFinished, getOnScrollStarted, getOnSwipeDown, getOnSwipeLeft, getOnSwipeRight, getOnSwipeUp, getOnTouchMoved, getOnTouchPressed, getOnTouchReleased, getOnTouchStationary, getOnZoom, getOnZoomFinished, getOnZoomStarted, getOpacity, getParent, getProperties, getPseudoClassStates, getRotate, getRotationAxis, getScaleX, getScaleY, getScaleZ, getScene, getStyle, getStyleableParent, getStyleClass, getTransforms, getTranslateX, getTranslateY, getTranslateZ, getTypeSelector, getUserData, getViewOrder, hasProperties, hoverProperty, idProperty, inputMethodRequestsProperty, intersects, intersects, isCache, isDisable, isDisabled, isFocused, isFocusTraversable, isHover, isManaged, isMouseTransparent, isPickOnBounds, isPressed, isVisible, layoutBoundsProperty, layoutXProperty, layoutYProperty, localToParent, localToParent, localToParent, localToParent, localToParent, localToParentTransformProperty, localToScene, localToScene, localToScene, localToScene, localToScene, localToScene, localToScene, localToScene, localToScene, localToScene, localToSceneTransformProperty, localToScreen, localToScreen, localToScreen, localToScreen, localToScreen, lookupAll, managedProperty, mouseTransparentProperty, nodeOrientationProperty, notifyAccessibleAttributeChanged, onContextMenuRequestedProperty, onDragDetectedProperty, onDragDoneProperty, onDragDroppedProperty, onDragEnteredProperty, onDragExitedProperty, onDragOverProperty, onInputMethodTextChangedProperty, onKeyPressedProperty, onKeyReleasedProperty, onKeyTypedProperty, onMouseClickedProperty, onMouseDragEnteredProperty, onMouseDragExitedProperty, onMouseDraggedProperty, onMouseDragOverProperty, onMouseDragReleasedProperty, onMouseEnteredProperty, onMouseExitedProperty, onMouseMovedProperty, onMousePressedProperty, onMouseReleasedProperty, onRotateProperty, onRotationFinishedProperty, onRotationStartedProperty, onScrollFinishedProperty, onScrollProperty, onScrollStartedProperty, onSwipeDownProperty, onSwipeLeftProperty, onSwipeRightProperty, onSwipeUpProperty, onTouchMovedProperty, onTouchPressedProperty, onTouchReleasedProperty, onTouchStationaryProperty, onZoomFinishedProperty, onZoomProperty, onZoomStartedProperty, opacityProperty, parentProperty, parentToLocal, parentToLocal, parentToLocal, parentToLocal, parentToLocal, pickOnBoundsProperty, pressedProperty, pseudoClassStateChanged, relocate, removeEventFilter, removeEventHandler, requestFocus, resizeRelocate, rotateProperty, rotationAxisProperty, scaleXProperty, scaleYProperty, scaleZProperty, sceneProperty, sceneToLocal, sceneToLocal, sceneToLocal, sceneToLocal, sceneToLocal, sceneToLocal, sceneToLocal, sceneToLocal, screenToLocal, screenToLocal, screenToLocal, setAccessibleHelp, setAccessibleRole, setAccessibleRoleDescription, setAccessibleText, setBlendMode, setCache, setCacheHint, setClip, setCursor, setDepthTest, setDisable, setDisabled, setEffect, setEventDispatcher, setEventHandler, setFocused, setFocusTraversable, setHover, setId, setInputMethodRequests, setLayoutX, setLayoutY, setManaged, setMouseTransparent, setNodeOrientation, setOnContextMenuRequested, setOnDragDetected, setOnDragDone, setOnDragDropped, setOnDragEntered, setOnDragExited, setOnDragOver, setOnInputMethodTextChanged, setOnKeyPressed, setOnKeyReleased, setOnKeyTyped, setOnMouseClicked, setOnMouseDragEntered, setOnMouseDragExited, setOnMouseDragged, setOnMouseDragOver, setOnMouseDragReleased, setOnMouseEntered, setOnMouseExited, setOnMouseMoved, setOnMousePressed, setOnMouseReleased, setOnRotate, setOnRotationFinished, setOnRotationStarted, setOnScroll, setOnScrollFinished, setOnScrollStarted, setOnSwipeDown, setOnSwipeLeft, setOnSwipeRight, setOnSwipeUp, setOnTouchMoved, setOnTouchPressed, setOnTouchReleased, setOnTouchStationary, setOnZoom, setOnZoomFinished, setOnZoomStarted, setOpacity, setPickOnBounds, setPressed, setRotate, setRotationAxis, setScaleX, setScaleY, setScaleZ, setStyle, setTranslateX, setTranslateY, setTranslateZ, setUserData, setViewOrder, setVisible, snapshot, snapshot, startDragAndDrop, startFullDrag, styleProperty, toBack, toFront, translateXProperty, translateYProperty, translateZProperty, usesMirroring, viewOrderProperty, visibleProperty`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

    - ### Methods inherited from interface javafx.css.Styleable

      `getStyleableNode`

- - ### Property Detail

    - #### converter

          public final ObjectProperty<StringConverter<T>> converterProperty

      The `StringConverter` property.
      Returns:
        the `StringConverter` property

    - #### comboBoxEditable

          public final BooleanProperty comboBoxEditableProperty

      A property representing whether the ComboBox, when shown to the user, is editable or not.
      See Also:
        `isComboBoxEditable()`, `setComboBoxEditable(boolean)`

  - ### Constructor Detail

    - #### ComboBoxListCell

          public ComboBoxListCell()

      Creates a default ComboBoxListCell with an empty items list.

    - #### ComboBoxListCell

          @SafeVarargs
          public ComboBoxListCell​(T... items)

      Creates a default `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown.
      Parameters:
        `items` - The items to show in the ComboBox popup menu when selected by the user.

    - #### ComboBoxListCell

          @SafeVarargs
          public ComboBoxListCell​(StringConverter<T> converter,
                                  T... items)

      Creates a `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown, and the `StringConverter` being used to convert the item in to a user-readable form.
      Parameters:
        `converter` - A `StringConverter` that can convert an item of type T into a user-readable string so that it may then be shown in the ComboBox popup menu.
        `items` - The items to show in the ComboBox popup menu when selected by the user.

    - #### ComboBoxListCell

          public ComboBoxListCell​(ObservableList<T> items)

      Creates a default `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown.
      Parameters:
        `items` - The items to show in the ComboBox popup menu when selected by the user.

    - #### ComboBoxListCell

          public ComboBoxListCell​(StringConverter<T> converter,
                                  ObservableList<T> items)

      Creates a `ComboBoxListCell` instance with the given items being used to populate the `ComboBox` when it is shown, and the `StringConverter` being used to convert the item in to a user-readable form.
      Parameters:
        `converter` - A `StringConverter` that can convert an item of type T into a user-readable string so that it may then be shown in the ComboBox popup menu.
        `items` - The items to show in the ComboBox popup menu when selected by the user.

  - ### Method Detail

    - #### forListView

          @SafeVarargs
          public static <T> Callback<ListView<T>,​ListCell<T>> forListView​(T... items)

      Creates a ComboBox cell factory for use in `ListView` controls. By default, the ComboBoxCell is rendered as a `Label` when not being edited, and as a ComboBox when in editing mode. The ComboBox will, by default, stretch to fill the entire list cell.
      Type Parameters:
        `T` - The type of the elements contained within the ListView.
      Parameters:
        `items` - Zero or more items that will be shown to the user when the `ComboBox` menu is showing. These items must be of the same type as the ListView items list, such that upon selection, they replace the existing value in the `items` list.
      Returns:
        A `Callback` that will return a ListCell that is able to work on the type of element contained within the ListView.

    - #### forListView

          @SafeVarargs
          public static <T> Callback<ListView<T>,​ListCell<T>> forListView​(StringConverter<T> converter,
                                                                                T... items)

      Creates a ComboBox cell factory for use in `ListView` controls. By default, the ComboBoxCell is rendered as a `Label` when not being edited, and as a ComboBox when in editing mode. The ComboBox will, by default, stretch to fill the entire list cell.
      Type Parameters:
        `T` - The type of the elements contained within the ListView.
      Parameters:
        `converter` - A `StringConverter` to convert the given item (of type T) to a String for displaying to the user.
        `items` - Zero or more items that will be shown to the user when the `ComboBox` menu is showing. These items must be of the same type as the ListView items list, such that upon selection, they replace the existing value in the `items` list.
      Returns:
        A `Callback` that will return a ListCell that is able to work on the type of element contained within the ListView.

    - #### forListView

          public static <T> Callback<ListView<T>,​ListCell<T>> forListView​(ObservableList<T> items)

      Creates a ComboBox cell factory for use in `ListView` controls. By default, the ComboBoxCell is rendered as a `Label` when not being edited, and as a ComboBox when in editing mode. The ComboBox will, by default, stretch to fill the entire list cell.
      Type Parameters:
        `T` - The type of the elements contained within the ListView.
      Parameters:
        `items` - An `ObservableList` containing zero or more items that will be shown to the user when the `ComboBox` menu is showing. These items must be of the same type as the ListView items sequence, such that upon selection, they replace the existing value in the `items` list.
      Returns:
        A `Callback` that will return a ListCell that is able to work on the type of element contained within the ListView.

    - #### forListView

          public static <T> Callback<ListView<T>,​ListCell<T>> forListView​(StringConverter<T> converter,
                                                                                ObservableList<T> items)

      Creates a ComboBox cell factory for use in `ListView` controls. By default, the ComboBoxCell is rendered as a `Label` when not being edited, and as a ComboBox when in editing mode. The ComboBox will, by default, stretch to fill the entire list cell.
      Type Parameters:
        `T` - The type of the elements contained within the ListView.
      Parameters:
        `converter` - A `StringConverter` to convert the given item (of type T) to a String for displaying to the user.
        `items` - An `ObservableList` containing zero or more items that will be shown to the user when the `ComboBox` menu is showing. These items must be of the same type as the ListView items sequence, such that upon selection, they replace the existing value in the `items` list.
      Returns:
        A `Callback` that will return a ListCell that is able to work on the type of element contained within the ListView.

    - #### converterProperty

          public final ObjectProperty<StringConverter<T>> converterProperty()

      The `StringConverter` property.
      Returns:
        the `StringConverter` property

    - #### setConverter

          public final void setConverter​(StringConverter<T> value)

      Sets the `StringConverter` to be used in this cell.
      Parameters:
        `value` - the `StringConverter` to be used in this cell

    - #### getConverter

          public final StringConverter<T> getConverter()

      Returns the `StringConverter` used in this cell.
      Returns:
        the `StringConverter` used in this cell

    - #### comboBoxEditableProperty

          public final BooleanProperty comboBoxEditableProperty()

      A property representing whether the ComboBox, when shown to the user, is editable or not.
      See Also:
        `isComboBoxEditable()`, `setComboBoxEditable(boolean)`

    - #### setComboBoxEditable

          public final void setComboBoxEditable​(boolean value)

      Configures the ComboBox to be editable (to allow user input outside of the options provide in the dropdown list).
      Parameters:
        `value` - the editable value for this ComboBox

    - #### isComboBoxEditable

          public final boolean isComboBoxEditable()

      Returns true if the ComboBox is editable.
      Returns:
        true if the ComboBox is editable

    - #### getItems

          public ObservableList<T> getItems()

      Returns the items to be displayed in the ChoiceBox when it is showing.
      Returns:
        the items to be displayed in the ChoiceBox when it is showing

    - #### startEdit

          public void startEdit()

      Call this function to transition from a non-editing state into an editing state, if the cell is editable. If this cell is already in an editing state, it will stay in it.
      Overrides:
        `startEdit` in class `ListCell<T>`

    - #### cancelEdit

          public void cancelEdit()

      Call this function to transition from an editing state into a non-editing state, without saving any user input.
      Overrides:
        `cancelEdit` in class `ListCell<T>`

    - #### updateItem

          public void updateItem​(T item,
                                 boolean empty)

      The updateItem method should not be called by developers, but it is the best method for developers to override to allow for them to customise the visuals of the cell. To clarify, developers should never call this method in their code (they should leave it up to the UI control, such as the `ListView` control) to call this method. However, the purpose of having the updateItem method is so that developers, when specifying custom cell factories (again, like the ListView `cell factory`), the updateItem method can be overridden to allow for complete customisation of the cell.

      It is very important that subclasses of Cell override the updateItem method properly, as failure to do so will lead to issues such as blank cells or cells with unexpected content appearing within them. Here is an example of how to properly override the updateItem method:

           protected void updateItem(T item, boolean empty) {
               super.updateItem(item, empty);

               if (empty || item == null) {
                   setText(null);
                   setGraphic(null);
               } else {
                   setText(item.toString());
               }
           }

      Note in this code sample two important points:

      1. We call the super.updateItem(T, boolean) method. If this is not done, the item and empty properties are not correctly set, and you are likely to end up with graphical issues.
      2. We test for the `empty` condition, and if true, we set the text and graphic properties to null. If we do not do this, it is almost guaranteed that end users will see graphical artifacts in cells unexpectedly.
      Overrides:
        `updateItem` in class `Cell<T>`
      Parameters:
        `item` - The new item for the cell.
        `empty` - whether or not this cell represents data from the list. If it is empty, then it does not represent any domain data, but is a cell being used to render an "empty" row.