Module javafx.controls
Package javafx.scene.control.skin

## Class MenuBarSkin

- java.lang.Object
- - javafx.scene.control.SkinBase<MenuBar>
  - - javafx.scene.control.skin.MenuBarSkin

- All Implemented Interfaces:
    `Skin<MenuBar>`

      public class MenuBarSkin
      extends SkinBase<MenuBar>

  Default skin implementation for the `MenuBar` control. In essence it is a simple toolbar. For the time being there is no overflow behavior and we just hide nodes which fall outside the bounds.
  Since:
    9
  See Also:
    `MenuBar`

- - ### Property Summary

    Properties
    Type | Property | Description
    --- | --- | ---
    `ObjectProperty<Pos>` | `containerAlignment` | Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).
    `DoubleProperty` | `spacing` | Specifies the spacing between menu buttons on the MenuBar.

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `MenuBarSkin​(MenuBar control)` | Creates a new MenuBarSkin instance, installing the necessary child nodes into the Control `children` list, as well as the necessary input mappings for handling key, mouse, etc events.

  - ### Method Summary

    Modifier and Type | Method | Description
    --- | --- | ---
    `protected double` | `computeMaxHeight​(double width, double topInset, double rightInset, double bottomInset, double leftInset)` | Computes the maximum allowable height of the Skin, based on the provided width.
    `protected double` | `computeMinHeight​(double width, double topInset, double rightInset, double bottomInset, double leftInset)` | Computes the minimum allowable height of the Skin, based on the provided width.
    `protected double` | `computeMinWidth​(double height, double topInset, double rightInset, double bottomInset, double leftInset)` | Computes the minimum allowable width of the Skin, based on the provided height.
    `protected double` | `computePrefHeight​(double width, double topInset, double rightInset, double bottomInset, double leftInset)` | Calculates the preferred height of this `SkinBase`.
    `protected double` | `computePrefWidth​(double height, double topInset, double rightInset, double bottomInset, double leftInset)` | Calculates the preferred width of this `SkinBase`.
    `ObjectProperty<Pos>` | `containerAlignmentProperty()` | Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).
    `void` | `dispose()` | Called by a Skinnable when the Skin is replaced on the Skinnable.
    `static List<CssMetaData<? extends Styleable,​?>>` | `getClassCssMetaData()` | Returns the CssMetaData associated with this class, which may include the CssMetaData of its superclasses.
    `Pos` | `getContainerAlignment()` | Gets the value of the property containerAlignment.
    `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.
    `double` | `getSpacing()` | Gets the value of the property spacing.
    `protected void` | `layoutChildren​(double x, double y, double w, double h)` | Called during the layout pass of the scenegraph.
    `protected Object` | `queryAccessibleAttribute​(AccessibleAttribute attribute, Object... parameters)` | This method is called by the assistive technology to request the value for an attribute.
    `void` | `setContainerAlignment​(Pos value)` | Sets the value of the property containerAlignment.
    `static void` | `setDefaultSystemMenuBar​(MenuBar menuBar)` | Set the default system menu bar.
    `void` | `setSpacing​(double value)` | Sets the value of the property spacing.
    `protected double` | `snappedBottomInset()` | Utility method to get the bottom inset which includes padding and border inset.
    `protected double` | `snappedLeftInset()` | Utility method to get the left inset which includes padding and border inset.
    `protected double` | `snappedRightInset()` | Utility method to get the right inset which includes padding and border inset.
    `protected double` | `snappedTopInset()` | Utility method to get the top inset which includes padding and border inset.
    `DoubleProperty` | `spacingProperty()` | Specifies the spacing between menu buttons on the MenuBar.

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

      `computeBaselineOffset, computeMaxWidth, consumeMouseEvents, executeAccessibleAction, getChildren, getNode, getSkinnable, layoutInArea, layoutInArea, layoutInArea, positionInArea, positionInArea, pseudoClassStateChanged, registerChangeListener, snapPosition, snapPositionX, snapPositionY, snapSize, snapSizeX, snapSizeY, snapSpace, snapSpaceX, snapSpaceY, unregisterChangeListeners`

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

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

- - ### Property Detail

    - #### spacing

          public final DoubleProperty spacingProperty

      Specifies the spacing between menu buttons on the MenuBar.
      See Also:
        `getSpacing()`, `setSpacing(double)`

    - #### containerAlignment

          public final ObjectProperty<Pos> containerAlignmentProperty

      Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).
      See Also:
        `getContainerAlignment()`, `setContainerAlignment(Pos)`

  - ### Constructor Detail

    - #### MenuBarSkin

          public MenuBarSkin​(MenuBar control)

      Creates a new MenuBarSkin instance, installing the necessary child nodes into the Control `children` list, as well as the necessary input mappings for handling key, mouse, etc events.
      Parameters:
        `control` - The control that this skin should be installed onto.

  - ### Method Detail

    - #### setDefaultSystemMenuBar

          public static void setDefaultSystemMenuBar​(MenuBar menuBar)

      Set the default system menu bar. This allows an application to keep menu in the system menu bar after the last Window is closed.
      Parameters:
        `menuBar` - the menu bar

    - #### setSpacing

          public final void setSpacing​(double value)

      Sets the value of the property spacing.
      Property description:
        Specifies the spacing between menu buttons on the MenuBar.

    - #### getSpacing

          public final double getSpacing()

      Gets the value of the property spacing.
      Property description:
        Specifies the spacing between menu buttons on the MenuBar.

    - #### spacingProperty

          public final DoubleProperty spacingProperty()

      Specifies the spacing between menu buttons on the MenuBar.
      See Also:
        `getSpacing()`, `setSpacing(double)`

    - #### setContainerAlignment

          public final void setContainerAlignment​(Pos value)

      Sets the value of the property containerAlignment.
      Property description:
        Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).

    - #### getContainerAlignment

          public final Pos getContainerAlignment()

      Gets the value of the property containerAlignment.
      Property description:
        Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).

    - #### containerAlignmentProperty

          public final ObjectProperty<Pos> containerAlignmentProperty()

      Specifies the alignment of the menu buttons inside the MenuBar (by default it is Pos.TOP_LEFT).
      See Also:
        `getContainerAlignment()`, `setContainerAlignment(Pos)`

    - #### dispose

          public void dispose()

      Called by a Skinnable when the Skin is replaced on the Skinnable. This method allows a Skin to implement any logic necessary to clean up itself after the Skin is no longer needed. It may be used to release native resources. The methods `Skin.getSkinnable()` and `Skin.getNode()` should return null following a call to dispose. Calling dispose twice has no effect.
      Specified by:
        `dispose` in interface `Skin<MenuBar>`
      Overrides:
        `dispose` in class `SkinBase<MenuBar>`

    - #### snappedTopInset

          protected double snappedTopInset()

      Utility method to get the top inset which includes padding and border inset. Then snapped to whole pixels if getSkinnable().isSnapToPixel() is true.
      Overrides:
        `snappedTopInset` in class `SkinBase<MenuBar>`
      Returns:
        Rounded up insets top

    - #### snappedBottomInset

          protected double snappedBottomInset()

      Utility method to get the bottom inset which includes padding and border inset. Then snapped to whole pixels if getSkinnable().isSnapToPixel() is true.
      Overrides:
        `snappedBottomInset` in class `SkinBase<MenuBar>`
      Returns:
        Rounded up insets bottom

    - #### snappedLeftInset

          protected double snappedLeftInset()

      Utility method to get the left inset which includes padding and border inset. Then snapped to whole pixels if getSkinnable().isSnapToPixel() is true.
      Overrides:
        `snappedLeftInset` in class `SkinBase<MenuBar>`
      Returns:
        Rounded up insets left

    - #### snappedRightInset

          protected double snappedRightInset()

      Utility method to get the right inset which includes padding and border inset. Then snapped to whole pixels if getSkinnable().isSnapToPixel() is true.
      Overrides:
        `snappedRightInset` in class `SkinBase<MenuBar>`
      Returns:
        Rounded up insets right

    - #### layoutChildren

          protected void layoutChildren​(double x,
                                        double y,
                                        double w,
                                        double h)

      Called during the layout pass of the scenegraph.
      Overrides:
        `layoutChildren` in class `SkinBase<MenuBar>`
      Parameters:
        `x` - the x position
        `y` - the y position
        `w` - the width
        `h` - the height

    - #### computeMinWidth

          protected double computeMinWidth​(double height,
                                           double topInset,
                                           double rightInset,
                                           double bottomInset,
                                           double leftInset)

      Computes the minimum allowable width of the Skin, based on the provided height.
      Overrides:
        `computeMinWidth` in class `SkinBase<MenuBar>`
      Parameters:
        `height` - The height of the Skin, in case this value might dictate the minimum width.
        `topInset` - the pixel snapped top inset
        `rightInset` - the pixel snapped right inset
        `bottomInset` - the pixel snapped bottom inset
        `leftInset` - the pixel snapped left inset
      Returns:
        A double representing the minimum width of this Skin.

    - #### computePrefWidth

          protected double computePrefWidth​(double height,
                                            double topInset,
                                            double rightInset,
                                            double bottomInset,
                                            double leftInset)

      Calculates the preferred width of this `SkinBase`. The default implementation calculates this width as the width of the area occupied by its managed children when they are positioned at their current positions at their preferred widths.
      Overrides:
        `computePrefWidth` in class `SkinBase<MenuBar>`
      Parameters:
        `height` - the height that should be used if preferred width depends on it
        `topInset` - the pixel snapped top inset
        `rightInset` - the pixel snapped right inset
        `bottomInset` - the pixel snapped bottom inset
        `leftInset` - the pixel snapped left inset
      Returns:
        the calculated preferred width

    - #### computeMinHeight

          protected double computeMinHeight​(double width,
                                            double topInset,
                                            double rightInset,
                                            double bottomInset,
                                            double leftInset)

      Computes the minimum allowable height of the Skin, based on the provided width.
      Overrides:
        `computeMinHeight` in class `SkinBase<MenuBar>`
      Parameters:
        `width` - The width of the Skin, in case this value might dictate the minimum height.
        `topInset` - the pixel snapped top inset
        `rightInset` - the pixel snapped right inset
        `bottomInset` - the pixel snapped bottom inset
        `leftInset` - the pixel snapped left inset
      Returns:
        A double representing the minimum height of this Skin.

    - #### computePrefHeight

          protected double computePrefHeight​(double width,
                                             double topInset,
                                             double rightInset,
                                             double bottomInset,
                                             double leftInset)

      Calculates the preferred height of this `SkinBase`. The default implementation calculates this height as the height of the area occupied by its managed children when they are positioned at their current positions at their preferred heights.
      Overrides:
        `computePrefHeight` in class `SkinBase<MenuBar>`
      Parameters:
        `width` - the width that should be used if preferred height depends on it
        `topInset` - the pixel snapped top inset
        `rightInset` - the pixel snapped right inset
        `bottomInset` - the pixel snapped bottom inset
        `leftInset` - the pixel snapped left inset
      Returns:
        the calculated preferred height

    - #### computeMaxHeight

          protected double computeMaxHeight​(double width,
                                            double topInset,
                                            double rightInset,
                                            double bottomInset,
                                            double leftInset)

      Computes the maximum allowable height of the Skin, based on the provided width.
      Overrides:
        `computeMaxHeight` in class `SkinBase<MenuBar>`
      Parameters:
        `width` - The width of the Skin, in case this value might dictate the maximum height.
        `topInset` - the pixel snapped top inset
        `rightInset` - the pixel snapped right inset
        `bottomInset` - the pixel snapped bottom inset
        `leftInset` - the pixel snapped left inset
      Returns:
        A double representing the maximum height of this Skin.

    - #### getClassCssMetaData

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

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

    - #### 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.
      Overrides:
        `getCssMetaData` in class `SkinBase<MenuBar>`
      Returns:
        The CssMetaData associated with this node, which may include the CssMetaData of its superclasses.

    - #### queryAccessibleAttribute

          protected Object queryAccessibleAttribute​(AccessibleAttribute attribute,
                                                    Object... parameters)

      This method is called by the assistive technology to request the value for an attribute.

      This method is commonly overridden by subclasses to implement attributes that are required for a specific role.
      If a particular attribute is not handled, the superclass implementation must be called.

      Overrides:
        `queryAccessibleAttribute` in class `SkinBase<MenuBar>`
      Parameters:
        `attribute` - the requested attribute
        `parameters` - optional list of parameters
      Returns:
        the value for the requested attribute
      See Also:
        `AccessibleAttribute`, `Node.queryAccessibleAttribute(javafx.scene.AccessibleAttribute, java.lang.Object...)`