ButtonBar (JavaFX 19)
Description: declaration: module: javafx.controls, package: javafx.scene.control, class: ButtonBar

Module javafx.controls
Package javafx.scene.control

# Class ButtonBar

java.lang.Object
javafx.scene.Node
javafx.scene.Parent
javafx.scene.layout.Region
javafx.scene.control.Control
javafx.scene.control.ButtonBar

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

public class ButtonBar extends Control
A ButtonBar is essentially a `HBox`, with the additional functionality for operating system specific button placement. In other words, any Node may be annotated (via the `setButtonData(Node, ButtonData)` method, placed inside a ButtonBar (via the `getButtons()` list), and will then be positioned relative to all other nodes in the button list based on their annotations, as well as the overarching `button order` specified for the ButtonBar.

## Uniform button sizing

By default all buttons are uniformly sized in a ButtonBar, meaning that all buttons take the width of the widest button. It is possible to opt-out of this on a per-button basis, but calling the `setButtonUniformSize(Node, boolean)` method with a boolean value of false.

If a button is excluded from uniform sizing, it is both excluded from being resized away from its preferred size, and also excluded from the measuring process, so its size will not influence the maximum size calculated for all buttons in the ButtonBar.

## Screenshots

Because a ButtonBar comes with built-in support for Windows, Mac OS and Linux, there are three screenshots shown below, with the same buttons laid out on each of the three operating systems.

Windows:

Mac OS:

Linux:

## Code Samples

Instantiating and using the ButtonBar is simple, simply do the following:

     // Create the ButtonBar instance
     ButtonBar buttonBar = new ButtonBar();

     // Create the buttons to go into the ButtonBar
     Button yesButton = new Button("Yes");
     ButtonBar.setButtonData(yesButton, ButtonData.YES);

     Button noButton = new Button("No");
     ButtonBar.setButtonData(noButton, ButtonData.NO);

     // Add buttons to the ButtonBar
     buttonBar.getButtons().addAll(yesButton, noButton);

The code sample above will position the Yes and No buttons relative to the users operating system. This means that on Windows and Linux the Yes button will come before the No button, whereas on Mac OS it'll be No and then Yes.

In most cases the OS-specific layout is the best choice, but in cases where you want a custom layout, this is achieved be modifying the `button order property`. These are cryptic-looking strings that are shorthand representations for the button order. The built-in orders for Windows, Mac OS and Linux are:

ButtonBar Layout Table
Operating System | Button Order
--- | ---
Windows | L_E+U+FBXI_YNOCAH_R
Mac OS | L_HE+U+FBIX_NCYOA_R
Linux | L_HE+UNYACBXIO_R

You should refer to the `ButtonBar.ButtonData` enumeration for a description of what each of these characters mean. However, if your ButtonBar only consisted of `ButtonBar.ButtonData.YES` and `ButtonBar.ButtonData.NO` buttons, you always wanted the yes buttons before the no buttons, and you wanted the buttons to be `right-aligned`, you could do the following:

     // Create the ButtonBar instance
     ButtonBar buttonBar = new ButtonBar();

     // Set the custom button order
     buttonBar.setButtonOrder("+YN");

Since:
  JavaFX 8u40
See Also:
  - `ButtonBar.ButtonData`

- ## Property Summary

  Properties
  Type
  Property
  Description
  `final DoubleProperty`
  `buttonMinWidth`
  Specifies the minimum width of all buttons placed in this button bar.
  `final StringProperty`
  `buttonOrder`
  The order for the typical buttons in a standard button bar.

  ### Properties declared in class javafx.scene.control.Control

  `contextMenu, skin, tooltip`

  ### Properties declared in class javafx.scene.layout.Region

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

  ### Properties declared in class javafx.scene.Parent

  `needsLayout`

  ### Properties declared in class javafx.scene.Node

  `accessibleHelp, accessibleRoleDescription, accessibleRole, accessibleText, blendMode, boundsInLocal, boundsInParent, cacheHint, cache, clip, cursor, depthTest, disabled, disable, effectiveNodeOrientation, effect, eventDispatcher, focused, focusTraversable, focusVisible, focusWithin, 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`

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static enum`
  `ButtonBar.ButtonData`
  An enumeration of all available button data annotations.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String`
  `BUTTON_ORDER_LINUX`
  The default button ordering on Linux (specifically, GNOME).
  `static final String`
  `BUTTON_ORDER_MAC_OS`
  The default button ordering on Mac OS.
  `static final String`
  `BUTTON_ORDER_NONE`
  A button ordering string that specifies there is no button ordering.
  `static final String`
  `BUTTON_ORDER_WINDOWS`
  The default button ordering on Windows.

  ### Fields declared in class javafx.scene.layout.Region

  `USE_COMPUTED_SIZE, USE_PREF_SIZE`

  ### Fields declared in class javafx.scene.Node

  `BASELINE_OFFSET_SAME_AS_HEIGHT`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `ButtonBar()`
  Creates a default ButtonBar instance using the default properties for the users operating system.
  `ButtonBar(String buttonOrder)`
  Creates a ButtonBar with the given button order (refer to `buttonOrderProperty()` for more information).

- ## Method Summary

  Modifier and Type
  Method
  Description
  `final DoubleProperty`
  `buttonMinWidthProperty()`
  Specifies the minimum width of all buttons placed in this button bar.
  `final StringProperty`
  `buttonOrderProperty()`
  The order for the typical buttons in a standard button bar.
  `static ButtonBar.ButtonData`
  `getButtonData(Node button)`
  Returns the previously set ButtonData property on the given button.
  `final double`
  `getButtonMinWidth()`
  Returns the minimum width of all buttons placed in this button bar.
  `final String`
  `getButtonOrder()`
  Returns the current `button order`.
  `final ObservableList<Node>`
  `getButtons()`
  Placing buttons inside this ObservableList will instruct the ButtonBar to position them relative to each other based on their specified `ButtonBar.ButtonData`.
  `protected Boolean`
  `getInitialFocusTraversable()`
  Returns the initial focus traversable state of this control, for use by the JavaFX CSS engine to correctly set its initial value.
  `static boolean`
  `isButtonUniformSize(Node button)`
  Returns whether the given node is part of the uniform sizing calculations or not.
  `static void`
  `setButtonData(Node button, ButtonBar.ButtonData buttonData)`
  Sets the given ButtonData on the given button.
  `final void`
  `setButtonMinWidth(double value)`
  Sets the minimum width of all buttons placed in this button bar.
  `final void`
  `setButtonOrder(String buttonOrder)`
  Sets the `button order`
  `static void`
  `setButtonUniformSize(Node button, boolean uniformSize)`
  By default all buttons are uniformly sized in a ButtonBar, meaning that all buttons take the width of the widest button.

  ### Methods declared in class javafx.scene.control.Control

  `computeMaxHeight, computeMaxWidth, computeMinHeight, computeMinWidth, contextMenuProperty, createDefaultSkin, getClassCssMetaData, getContextMenu, getControlCssMetaData, getCssMetaData, getSkin, getTooltip, isResizable, setContextMenu, setSkin, setTooltip, skinProperty, tooltipProperty`

  ### Methods declared in class javafx.scene.layout.Region

  `backgroundProperty, borderProperty, cacheShapeProperty, centerShapeProperty, computePrefHeight, computePrefWidth, 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 declared in class javafx.scene.Parent

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

  ### Methods declared in 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, focusVisibleProperty, focusWithinProperty, getAccessibleHelp, getAccessibleRole, getAccessibleRoleDescription, getAccessibleText, getBlendMode, getBoundsInLocal, getBoundsInParent, getCacheHint, getClip, getContentBias, 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, isFocusVisible, isFocusWithin, 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, lookup, 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, queryAccessibleAttribute, 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 declared in class java.lang.Object

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

  ### Methods declared in interface javafx.css.Styleable

  `getStyleableNode`

- ## Property Details

  - ### buttonOrder

    public final StringProperty buttonOrderProperty
    The order for the typical buttons in a standard button bar. It is one letter per `ButtonBar.ButtonData` enumeration value. Default button orders for operating systems are also available: `BUTTON_ORDER_WINDOWS`, `BUTTON_ORDER_MAC_OS`, and `BUTTON_ORDER_LINUX`.
    See Also:
      - `getButtonOrder()`
      - `setButtonOrder(String)`

  - ### buttonMinWidth

    public final DoubleProperty buttonMinWidthProperty
    Specifies the minimum width of all buttons placed in this button bar.
    See Also:
      - `getButtonMinWidth()`
      - `setButtonMinWidth(double)`

- ## Field Details

  - ### BUTTON_ORDER_WINDOWS

    public static final String BUTTON_ORDER_WINDOWS
    The default button ordering on Windows.
    See Also:
      - Constant Field Values

  - ### BUTTON_ORDER_MAC_OS

    public static final String BUTTON_ORDER_MAC_OS
    The default button ordering on Mac OS.
    See Also:
      - Constant Field Values

  - ### BUTTON_ORDER_LINUX

    public static final String BUTTON_ORDER_LINUX
    The default button ordering on Linux (specifically, GNOME).
    See Also:
      - Constant Field Values

  - ### BUTTON_ORDER_NONE

    public static final String BUTTON_ORDER_NONE
    A button ordering string that specifies there is no button ordering. In other words, buttons will be placed in the order that exist in the `getButtons()` list. The only aspect of layout that makes this different than using an HBox is that the buttons are right-aligned.
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### ButtonBar

    public ButtonBar()
    Creates a default ButtonBar instance using the default properties for the users operating system.

  - ### ButtonBar

    public ButtonBar(String buttonOrder)
    Creates a ButtonBar with the given button order (refer to `buttonOrderProperty()` for more information).
    Parameters:
      `buttonOrder` - The button order to use in this button bar instance.

- ## Method Details

  - ### setButtonData

    public static void setButtonData(Node button, ButtonBar.ButtonData buttonData)
    Sets the given ButtonData on the given button. If this button is subsequently placed in a `ButtonBar` it will be placed in the correct position relative to all other buttons in the bar.
    Parameters:
      `button` - The button to annotate with the given `ButtonBar.ButtonData` value.
      `buttonData` - The ButtonData to designate the button as.

  - ### getButtonData

    public static ButtonBar.ButtonData getButtonData(Node button)
    Returns the previously set ButtonData property on the given button. If this was never set, this method will return null.
    Parameters:
      `button` - The button to return the previously set ButtonData for.
    Returns:
      the previously set ButtonData property on the given button

  - ### setButtonUniformSize

    public static void setButtonUniformSize(Node button, boolean uniformSize)
    By default all buttons are uniformly sized in a ButtonBar, meaning that all buttons take the width of the widest button. It is possible to opt-out of this on a per-button basis, but calling the setButtonUniformSize method with a boolean value of false.

    If a button is excluded from uniform sizing, it is both excluded from being resized away from its preferred size, and also excluded from the measuring process, so its size will not influence the maximum size calculated for all buttons in the ButtonBar.

    Parameters:
      `button` - The button to include / exclude from uniform sizing.
      `uniformSize` - Boolean true to force uniform sizing on the button, false to exclude the button from uniform sizing.

  - ### isButtonUniformSize

    public static boolean isButtonUniformSize(Node button)
    Returns whether the given node is part of the uniform sizing calculations or not. By default all nodes that have not opted out (via `setButtonUniformSize(Node, boolean)`) will return true here.
    Parameters:
      `button` - the button
    Returns:
      true if button is part of the uniform sizing calculations

  - ### getButtons

    public final ObservableList<Node> getButtons()
    Placing buttons inside this ObservableList will instruct the ButtonBar to position them relative to each other based on their specified `ButtonBar.ButtonData`. To set the ButtonData for a button, simply call `setButtonData(Node, ButtonData)`, passing in the relevant ButtonData.
    Returns:
      A list containing all buttons currently in the button bar, and allowing for further buttons to be added or removed.

  - ### buttonOrderProperty

    public final StringProperty buttonOrderProperty()
    The order for the typical buttons in a standard button bar. It is one letter per `ButtonBar.ButtonData` enumeration value. Default button orders for operating systems are also available: `BUTTON_ORDER_WINDOWS`, `BUTTON_ORDER_MAC_OS`, and `BUTTON_ORDER_LINUX`.
    See Also:
      - `getButtonOrder()`
      - `setButtonOrder(String)`

  - ### setButtonOrder

    public final void setButtonOrder(String buttonOrder)
    Sets the `button order`
    Parameters:
      `buttonOrder` - The currently set button order, which by default will be the OS-specific button order.

  - ### getButtonOrder

    public final String getButtonOrder()
    Returns the current `button order`.
    Returns:
      The current `button order`.

  - ### buttonMinWidthProperty

    public final DoubleProperty buttonMinWidthProperty()
    Specifies the minimum width of all buttons placed in this button bar.
    See Also:
      - `getButtonMinWidth()`
      - `setButtonMinWidth(double)`

  - ### setButtonMinWidth

    public final void setButtonMinWidth(double value)
    Sets the minimum width of all buttons placed in this button bar.
    Parameters:
      `value` - the minimum width value

  - ### getButtonMinWidth

    public final double getButtonMinWidth()
    Returns the minimum width of all buttons placed in this button bar.
    Returns:
      the minimum width value

  - ### getInitialFocusTraversable

    protected Boolean getInitialFocusTraversable()
    Returns the initial focus traversable state of this control, for use by the JavaFX CSS engine to correctly set its initial value. This method is overridden as by default UI controls have focus traversable set to true, but that is not appropriate for this control.
    Overrides:
      `getInitialFocusTraversable` in class `Control`
    Returns:
      the initial focus traversable state of this control
    Since:
      9