VBox (JavaFX 13)

Module javafx.graphics
Package javafx.scene.layout

## Class VBox

- java.lang.Object
- - javafx.scene.Node
  - - javafx.scene.Parent
    - - javafx.scene.layout.Region
      - - javafx.scene.layout.Pane
        - - javafx.scene.layout.VBox

- All Implemented Interfaces:
    `Styleable`, `EventTarget`

      public class VBox
      extends Pane

  VBox lays out its children in a single vertical column. If the vbox has a border and/or padding set, then the contents will be laid out within those insets.

  VBox example:

           VBox vbox = new VBox(8); // spacing = 8
           vbox.getChildren().addAll(new Button("Cut"), new Button("Copy"), new Button("Paste"));

  VBox will resize children (if resizable) to their preferred heights and uses its `fillWidth` property to determine whether to resize their widths to fill its own width or keep their widths to their preferred (fillWidth defaults to true). The alignment of the content is controlled by the `alignment` property, which defaults to Pos.TOP_LEFT.

  If a vbox is resized larger than its preferred height, by default it will keep children to their preferred heights, leaving the extra space unused. If an application wishes to have one or more children be allocated that extra space it may optionally set a vgrow constraint on the child. See "Optional Layout Constraints" for details.

  VBox lays out each managed child regardless of the child's visible property value; unmanaged children are ignored.

  ### Resizable Range

  A vbox's parent will resize the vbox within the vbox's resizable range during layout. By default the vbox computes this range based on its content as outlined in the table below.

  VBox Resize Table
  | width | height
  minimum | left/right insets plus the largest of the children's min widths. | top/bottom insets plus the sum of each child's min height plus spacing between each child.
  preferred | left/right insets plus the largest of the children's pref widths. | top/bottom insets plus the sum of each child's pref height plus spacing between each child.
  maximum | Double.MAX_VALUE | Double.MAX_VALUE

  A vbox's unbounded maximum width and height are an indication to the parent that it may be resized beyond its preferred size to fill whatever space is assigned to it.

  VBox provides properties for setting the size range directly. These properties default to the sentinel value USE_COMPUTED_SIZE, however the application may set them to other values as needed:

           vbox.setPrefWidth(400);

  Applications may restore the computed values by setting these properties back to USE_COMPUTED_SIZE.

  VBox does not clip its content by default, so it is possible that children's bounds may extend outside its own bounds if a child's min size prevents it from being fit within the vbox.

  ### Optional Layout Constraints

  An application may set constraints on individual children to customize VBox's layout. For each constraint, VBox provides a static method for setting it on the child.

  VBox Constraint Table
  Constraint | Type | Description
  --- | --- | ---
  vgrow | javafx.scene.layout.Priority | The vertical grow priority for the child.
  margin | javafx.geometry.Insets | Margin space around the outside of the child.

  For example, if a vbox needs the ListView to be allocated all extra space:

           VBox vbox = new VBox();
           ListView list = new ListView();
           VBox.setVgrow(list, Priority.ALWAYS);
           vbox.getChildren().addAll(new Label("Names:"), list);

  If more than one child has the same grow priority set, then the vbox will allocate equal amounts of space to each. VBox will only grow a child up to its maximum height, so if the child has a max height other than Double.MAX_VALUE, the application may need to override the max to allow it to grow.
  Since:
    JavaFX 2.0

- - ### Property Summary

    Properties
    Type | Property | Description
    --- | --- | ---
    `ObjectProperty<Pos>` | `alignment` | The overall alignment of children within the vbox's width and height.
    `BooleanProperty` | `fillWidth` | Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.
    `DoubleProperty` | `spacing` | The amount of vertical space between each child in the vbox.

    - ### 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
    --- | ---
    `VBox()` | Creates a VBox layout with spacing = 0 and alignment at TOP_LEFT.
    `VBox​(double spacing)` | Creates a VBox layout with the specified spacing between children.
    `VBox​(double spacing, Node... children)` | Creates an VBox layout with the specified spacing between children.
    `VBox​(Node... children)` | Creates an VBox layout with spacing = 0.

  - ### Method Summary

    All Methods Static Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `ObjectProperty<Pos>` | `alignmentProperty()` | The overall alignment of children within the vbox's width and height.
    `static void` | `clearConstraints​(Node child)` | Removes all vbox constraints from the child node.
    `protected double` | `computeMinHeight​(double width)` | Computes the minimum height of this region.
    `protected double` | `computeMinWidth​(double height)` | Computes the minimum width of this region.
    `protected double` | `computePrefHeight​(double width)` | Computes the preferred height of this region for the given width; Region subclasses should override this method to return an appropriate value based on their content and layout strategy.
    `protected double` | `computePrefWidth​(double height)` | Computes the preferred width of this region for the given height.
    `BooleanProperty` | `fillWidthProperty()` | Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.
    `Pos` | `getAlignment()` | Gets the value of the property alignment.
    `static List<CssMetaData<? extends Styleable,​?>>` | `getClassCssMetaData()` |
    `Orientation` | `getContentBias()` | Returns the orientation of a node's resizing bias for layout purposes.
    `List<CssMetaData<? extends Styleable,​?>>` | `getCssMetaData()` | This method should delegate to `Node.getClassCssMetaData()` so that a Node's CssMetaData can be accessed without the need for reflection.
    `static Insets` | `getMargin​(Node child)` | Returns the child's margin property if set.
    `double` | `getSpacing()` | Gets the value of the property spacing.
    `static Priority` | `getVgrow​(Node child)` | Returns the child's vgrow property if set.
    `boolean` | `isFillWidth()` | Gets the value of the property fillWidth.
    `protected void` | `layoutChildren()` | Invoked during the layout pass to layout the children in this `Parent`.
    `void` | `requestLayout()` | Requests a layout pass to be performed before the next scene is rendered.
    `void` | `setAlignment​(Pos value)` | Sets the value of the property alignment.
    `void` | `setFillWidth​(boolean value)` | Sets the value of the property fillWidth.
    `static void` | `setMargin​(Node child, Insets value)` | Sets the margin for the child when contained by a vbox.
    `void` | `setSpacing​(double value)` | Sets the value of the property spacing.
    `static void` | `setVgrow​(Node child, Priority value)` | Sets the vertical grow priority for the child when contained by an vbox.
    `DoubleProperty` | `spacingProperty()` | The amount of vertical space between each child in the vbox.

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

      `getChildren`

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

      `backgroundProperty, borderProperty, cacheShapeProperty, centerShapeProperty, computeMaxHeight, computeMaxWidth, getBackground, getBorder, getHeight, getInsets, getMaxHeight, getMaxWidth, getMinHeight, getMinWidth, getOpaqueInsets, getPadding, getPrefHeight, getPrefWidth, getShape, getUserAgentStylesheet, getWidth, heightProperty, insetsProperty, isCacheShape, isCenterShape, isResizable, 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

      `getBaselineOffset, getChildrenUnmodifiable, getManagedChildren, getStylesheets, isNeedsLayout, layout, lookup, needsLayoutProperty, queryAccessibleAttribute, 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, executeAccessibleAction, fireEvent, focusedProperty, focusTraversableProperty, getAccessibleHelp, getAccessibleRole, getAccessibleRoleDescription, getAccessibleText, getBlendMode, getBoundsInLocal, getBoundsInParent, getCacheHint, getClip, getCursor, getDepthTest, getEffect, getEffectiveNodeOrientation, getEventDispatcher, getId, getInitialCursor, getInitialFocusTraversable, 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, toString, 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

    - #### spacing

          public final DoubleProperty spacingProperty

      The amount of vertical space between each child in the vbox.
      See Also:
        `getSpacing()`, `setSpacing(double)`

    - #### alignment

          public final ObjectProperty<Pos> alignmentProperty

      The overall alignment of children within the vbox's width and height.
      See Also:
        `getAlignment()`, `setAlignment(Pos)`

    - #### fillWidth

          public final BooleanProperty fillWidthProperty

      Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.
      See Also:
        `isFillWidth()`, `setFillWidth(boolean)`

  - ### Constructor Detail

    - #### VBox

          public VBox()

      Creates a VBox layout with spacing = 0 and alignment at TOP_LEFT.

    - #### VBox

          public VBox​(double spacing)

      Creates a VBox layout with the specified spacing between children.
      Parameters:
        `spacing` - the amount of vertical space between each child

    - #### VBox

          public VBox​(Node... children)

      Creates an VBox layout with spacing = 0.
      Parameters:
        `children` - The initial set of children for this pane.
      Since:
        JavaFX 8.0

    - #### VBox

          public VBox​(double spacing,
                      Node... children)

      Creates an VBox layout with the specified spacing between children.
      Parameters:
        `spacing` - the amount of horizontal space between each child
        `children` - The initial set of children for this pane.
      Since:
        JavaFX 8.0

  - ### Method Detail

    - #### setVgrow

          public static void setVgrow​(Node child,
                                      Priority value)

      Sets the vertical grow priority for the child when contained by an vbox. If set, the vbox will use the priority to allocate additional space if the vbox is resized larger than it's preferred height. If multiple vbox children have the same vertical grow priority, then the extra space will be split evenly between them. If no vertical grow priority is set on a child, the vbox will never allocate it additional vertical space if available. Setting the value to null will remove the constraint.
      Parameters:
        `child` - the child of a vbox
        `value` - the horizontal grow priority for the child

    - #### getVgrow

          public static Priority getVgrow​(Node child)

      Returns the child's vgrow property if set.
      Parameters:
        `child` - the child node of a vbox
      Returns:
        the vertical grow priority for the child or null if no priority was set

    - #### setMargin

          public static void setMargin​(Node child,
                                       Insets value)

      Sets the margin for the child when contained by a vbox. If set, the vbox will layout the child so that it has the margin space around it. Setting the value to null will remove the constraint.
      Parameters:
        `child` - the child mode of a vbox
        `value` - the margin of space around the child

    - #### getMargin

          public static Insets getMargin​(Node child)

      Returns the child's margin property if set.
      Parameters:
        `child` - the child node of a vbox
      Returns:
        the margin for the child or null if no margin was set

    - #### clearConstraints

          public static void clearConstraints​(Node child)

      Removes all vbox constraints from the child node.
      Parameters:
        `child` - the child node

    - #### spacingProperty

          public final DoubleProperty spacingProperty()

      The amount of vertical space between each child in the vbox.
      See Also:
        `getSpacing()`, `setSpacing(double)`

    - #### setSpacing

          public final void setSpacing​(double value)

      Sets the value of the property spacing.
      Property description:
        The amount of vertical space between each child in the vbox.

    - #### getSpacing

          public final double getSpacing()

      Gets the value of the property spacing.
      Property description:
        The amount of vertical space between each child in the vbox.

    - #### alignmentProperty

          public final ObjectProperty<Pos> alignmentProperty()

      The overall alignment of children within the vbox's width and height.
      See Also:
        `getAlignment()`, `setAlignment(Pos)`

    - #### setAlignment

          public final void setAlignment​(Pos value)

      Sets the value of the property alignment.
      Property description:
        The overall alignment of children within the vbox's width and height.

    - #### getAlignment

          public final Pos getAlignment()

      Gets the value of the property alignment.
      Property description:
        The overall alignment of children within the vbox's width and height.

    - #### fillWidthProperty

          public final BooleanProperty fillWidthProperty()

      Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.
      See Also:
        `isFillWidth()`, `setFillWidth(boolean)`

    - #### setFillWidth

          public final void setFillWidth​(boolean value)

      Sets the value of the property fillWidth.
      Property description:
        Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.

    - #### isFillWidth

          public final boolean isFillWidth()

      Gets the value of the property fillWidth.
      Property description:
        Whether or not resizable children will be resized to fill the full width of the vbox or be resized to their preferred width and aligned according to the `alignment` hpos value.

    - #### getContentBias

          public Orientation getContentBias()

      Description copied from class: `Node`
      Returns the orientation of a node's resizing bias for layout purposes. If the node type has no bias, returns null. If the node is resizable and it's height depends on its width, returns HORIZONTAL, else if its width depends on its height, returns VERTICAL.

      Resizable subclasses should override this method to return an appropriate value.

      Overrides:
        `getContentBias` in class `Node`
      Returns:
        null unless one of its children has a content bias.
      See Also:
        `Node.isResizable()`, `Node.minWidth(double)`, `Node.minHeight(double)`, `Node.prefWidth(double)`, `Node.prefHeight(double)`, `Node.maxWidth(double)`, `Node.maxHeight(double)`

    - #### computeMinWidth

          protected double computeMinWidth​(double height)

      Description copied from class: `Region`
      Computes the minimum width of this region. Returns the sum of the left and right insets by default. region subclasses should override this method to return an appropriate value based on their content and layout strategy. If the subclass doesn't have a VERTICAL content bias, then the height parameter can be ignored.
      Overrides:
        `computeMinWidth` in class `Region`
      Parameters:
        `height` - the height that should be used if min width depends on it
      Returns:
        the computed minimum width of this region

    - #### computeMinHeight

          protected double computeMinHeight​(double width)

      Description copied from class: `Region`
      Computes the minimum height of this region. Returns the sum of the top and bottom insets by default. Region subclasses should override this method to return an appropriate value based on their content and layout strategy. If the subclass doesn't have a HORIZONTAL content bias, then the width parameter can be ignored.
      Overrides:
        `computeMinHeight` in class `Region`
      Parameters:
        `width` - the width that should be used if min height depends on it
      Returns:
        the computed minimum height for this region

    - #### computePrefWidth

          protected double computePrefWidth​(double height)

      Description copied from class: `Region`
      Computes the preferred width of this region for the given height. Region subclasses should override this method to return an appropriate value based on their content and layout strategy. If the subclass doesn't have a VERTICAL content bias, then the height parameter can be ignored.
      Overrides:
        `computePrefWidth` in class `Region`
      Parameters:
        `height` - the height that should be used if preferred width depends on it
      Returns:
        the computed preferred width for this region

    - #### computePrefHeight

          protected double computePrefHeight​(double width)

      Description copied from class: `Region`
      Computes the preferred height of this region for the given width; Region subclasses should override this method to return an appropriate value based on their content and layout strategy. If the subclass doesn't have a HORIZONTAL content bias, then the width parameter can be ignored.
      Overrides:
        `computePrefHeight` in class `Region`
      Parameters:
        `width` - the width that should be used if preferred height depends on it
      Returns:
        the computed preferred height for this region

    - #### requestLayout

          public void requestLayout()

      Description copied from class: `Parent`
      Requests a layout pass to be performed before the next scene is rendered. This is batched up asynchronously to happen once per "pulse", or frame of animation.

      If this parent is either a layout root or unmanaged, then it will be added directly to the scene's dirty layout list, otherwise requestParentLayout will be invoked.

      Overrides:
        `requestLayout` in class `Parent`

    - #### layoutChildren

          protected void layoutChildren()

      Description copied from class: `Parent`
      Invoked during the layout pass to layout the children in this `Parent`. By default it will only set the size of managed, resizable content to their preferred sizes and does not do any node positioning.

      Subclasses should override this function to layout content as needed.

      Overrides:
        `layoutChildren` in class `Parent`

    - #### getClassCssMetaData

          public static List<CssMetaData<? extends Styleable,​?>> getClassCssMetaData()

      Returns:
        The CssMetaData associated with this class, which may include the CssMetaData of its superclasses.
      Since:
        JavaFX 8.0

    - #### getCssMetaData

          public List<CssMetaData<? extends Styleable,​?>> getCssMetaData()

      This method should delegate to `Node.getClassCssMetaData()` so that a Node's CssMetaData can be accessed without the need for reflection.
      Specified by:
        `getCssMetaData` in interface `Styleable`
      Overrides:
        `getCssMetaData` in class `Region`
      Returns:
        The CssMetaData associated with this node, which may include the CssMetaData of its superclasses.
      Since:
        JavaFX 8.0