Menu (JavaFX 13)

Module javafx.controls
Package javafx.scene.control

## Class Menu

- java.lang.Object
- - javafx.scene.control.MenuItem
  - - javafx.scene.control.Menu

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

      @DefaultProperty("items")
      public class Menu
      extends MenuItem

  A popup menu of actionable items which is displayed to the user only upon request. When a menu is visible, in most use cases, the user can select one menu item before the menu goes back to its hidden state. This means the menu is a good place to put important functionality that does not necessarily need to be visible at all times to the user.

  Menus are typically placed in a `MenuBar`, or as a submenu of another Menu. If the intention is to offer a context menu when the user right-clicks in a certain area of their user interface, then this is the wrong control to use. This is because when Menu is added to the scenegraph, it has a visual representation that will result in it appearing on screen. Instead, `ContextMenu` should be used in this circumstance.

  Creating a Menu and inserting it into a MenuBar is easy, as shown below:

       Menu menu1 = new Menu("File");
       MenuBar menuBar = new MenuBar(menu1);

  A Menu is a subclass of `MenuItem` which means that it can be inserted into a Menu's `items` ObservableList, resulting in a submenu being created:

       MenuItem menu12 = new MenuItem("Open");
       menu1.getItems().add(menu12);

  The items ObservableList allows for any `MenuItem` type to be inserted, including its subclasses `Menu`, `MenuItem`, `RadioMenuItem`, `CheckMenuItem`, `CustomMenuItem` and `SeparatorMenuItem`. In order to insert an arbitrary `Node` to a Menu, a CustomMenuItem can be used. One exception to this general rule is that `SeparatorMenuItem` could be used for inserting a separator.

  Since:
    JavaFX 2.0
  See Also:
    `MenuBar`, `MenuItem`

- - ### Property Summary

    Properties
    Type | Property | Description
    --- | --- | ---
    `ObjectProperty<EventHandler<Event>>` | `onHidden` | Called just after the `ContextMenu` has been hidden.
    `ObjectProperty<EventHandler<Event>>` | `onHiding` | Called just prior to the `ContextMenu` being hidden.
    `ObjectProperty<EventHandler<Event>>` | `onShowing` | Called just prior to the `ContextMenu` being shown, even if the menu has no items to show.
    `ObjectProperty<EventHandler<Event>>` | `onShown` | Called just after the `ContextMenu` is shown.
    `ReadOnlyBooleanProperty` | `showing` | Indicates whether the `ContextMenu` is currently visible.

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

      `accelerator, disable, graphic, id, mnemonicParsing, onAction, onMenuValidation, parentMenu, parentPopup, style, text, visible`

  - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `static EventType<Event>` | `ON_HIDDEN` | Called when the contextMenu for this menu is hidden.
    `static EventType<Event>` | `ON_HIDING` | Called when the contextMenu for this menu will be hidden.
    `static EventType<Event>` | `ON_SHOWING` | Called when the contextMenu for this menu will be shown.
    `static EventType<Event>` | `ON_SHOWN` | Called when the contextMenu for this menu shows.

    - ### Fields inherited from class javafx.scene.control.MenuItem

      `MENU_VALIDATION_EVENT`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `Menu()` | Constructs a Menu with an empty string for its display text.
    `Menu​(String text)` | Constructs a Menu and sets the display text with the specified text.
    `Menu​(String text, Node graphic)` | Constructs a Menu and sets the display text with the specified text and sets the graphic `Node` to the given node.
    `Menu​(String text, Node graphic, MenuItem... items)` | Constructs a Menu and sets the display text with the specified text, the graphic `Node` to the given node, and inserts the given items into the `items` list.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `<E extends Event> void` | `addEventHandler​(EventType<E> eventType, EventHandler<E> eventHandler)` | Registers an event handler to this MenuItem.
    `EventDispatchChain` | `buildEventDispatchChain​(EventDispatchChain tail)` | Construct an event dispatch chain for this target.
    `ObservableList<MenuItem>` | `getItems()` | The items to show within this menu.
    `EventHandler<Event>` | `getOnHidden()` | Gets the value of the property onHidden.
    `EventHandler<Event>` | `getOnHiding()` | Gets the value of the property onHiding.
    `EventHandler<Event>` | `getOnShowing()` | Gets the value of the property onShowing.
    `EventHandler<Event>` | `getOnShown()` | Gets the value of the property onShown.
    `void` | `hide()` | Hides the `ContextMenu` if it was previously showing, and any showing submenus.
    `boolean` | `isShowing()` | Gets the value of the property showing.
    `ObjectProperty<EventHandler<Event>>` | `onHiddenProperty()` | Called just after the `ContextMenu` has been hidden.
    `ObjectProperty<EventHandler<Event>>` | `onHidingProperty()` | Called just prior to the `ContextMenu` being hidden.
    `ObjectProperty<EventHandler<Event>>` | `onShowingProperty()` | Called just prior to the `ContextMenu` being shown, even if the menu has no items to show.
    `ObjectProperty<EventHandler<Event>>` | `onShownProperty()` | Called just after the `ContextMenu` is shown.
    `<E extends Event> void` | `removeEventHandler​(EventType<E> eventType, EventHandler<E> eventHandler)` | Unregisters a previously registered event handler from this MenuItem.
    `void` | `setOnHidden​(EventHandler<Event> value)` | Sets the value of the property onHidden.
    `void` | `setOnHiding​(EventHandler<Event> value)` | Sets the value of the property onHiding.
    `void` | `setOnShowing​(EventHandler<Event> value)` | Sets the value of the property onShowing.
    `void` | `setOnShown​(EventHandler<Event> value)` | Sets the value of the property onShown.
    `void` | `show()` | If the Menu is not disabled and the `ContextMenu` is not already showing, then this will cause the `ContextMenu` to be shown.
    `ReadOnlyBooleanProperty` | `showingProperty()` | Indicates whether the `ContextMenu` is currently visible.

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

      `acceleratorProperty, disableProperty, fire, getAccelerator, getCssMetaData, getGraphic, getId, getOnAction, getOnMenuValidation, getParentMenu, getParentPopup, getProperties, getPseudoClassStates, getStyle, getStyleableNode, getStyleableParent, getStyleClass, getText, getTypeSelector, getUserData, graphicProperty, idProperty, isDisable, isMnemonicParsing, isVisible, mnemonicParsingProperty, onActionProperty, onMenuValidationProperty, parentMenuProperty, parentPopupProperty, setAccelerator, setDisable, setGraphic, setId, setMnemonicParsing, setOnAction, setOnMenuValidation, setParentMenu, setParentPopup, setStyle, setText, setUserData, setVisible, styleProperty, textProperty, toString, visibleProperty`

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

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

- - ### Property Detail

    - #### showing

          public final ReadOnlyBooleanProperty showingProperty

      Indicates whether the `ContextMenu` is currently visible.
      Default value:
        false
      See Also:
        `isShowing()`

    - #### onShowing

          public final ObjectProperty<EventHandler<Event>> onShowingProperty

      Called just prior to the `ContextMenu` being shown, even if the menu has no items to show. Note however that this won't be called if the menu does not have a valid anchor node.
      See Also:
        `getOnShowing()`, `setOnShowing(EventHandler)`

    - #### onShown

          public final ObjectProperty<EventHandler<Event>> onShownProperty

      Called just after the `ContextMenu` is shown.
      See Also:
        `getOnShown()`, `setOnShown(EventHandler)`

    - #### onHiding

          public final ObjectProperty<EventHandler<Event>> onHidingProperty

      Called just prior to the `ContextMenu` being hidden.
      See Also:
        `getOnHiding()`, `setOnHiding(EventHandler)`

    - #### onHidden

          public final ObjectProperty<EventHandler<Event>> onHiddenProperty

      Called just after the `ContextMenu` has been hidden.
      See Also:
        `getOnHidden()`, `setOnHidden(EventHandler)`

  - ### Field Detail

    - #### ON_SHOWING

          public static final EventType<Event> ON_SHOWING

      Called when the contextMenu for this menu will be shown. However if the contextMenu is empty then this will not be called.

    - #### ON_SHOWN

          public static final EventType<Event> ON_SHOWN

      Called when the contextMenu for this menu shows. However if the contextMenu is empty then this will not be called.

    - #### ON_HIDING

          public static final EventType<Event> ON_HIDING

      Called when the contextMenu for this menu will be hidden. However if the contextMenu is empty then this will not be called.

    - #### ON_HIDDEN

          public static final EventType<Event> ON_HIDDEN

      Called when the contextMenu for this menu is hidden. However if the contextMenu is empty then this will not be called.

  - ### Constructor Detail

    - #### Menu

          public Menu()

      Constructs a Menu with an empty string for its display text.
      Since:
        JavaFX 2.2

    - #### Menu

          public Menu​(String text)

      Constructs a Menu and sets the display text with the specified text.
      Parameters:
        `text` - the text to display on the menu button

    - #### Menu

          public Menu​(String text,
                      Node graphic)

      Constructs a Menu and sets the display text with the specified text and sets the graphic `Node` to the given node.
      Parameters:
        `text` - the text to display on the menu button
        `graphic` - the graphic to display on the menu button

    - #### Menu

          public Menu​(String text,
                      Node graphic,
                      MenuItem... items)

      Constructs a Menu and sets the display text with the specified text, the graphic `Node` to the given node, and inserts the given items into the `items` list.
      Parameters:
        `text` - the text to display on the menu button
        `graphic` - the graphic to display on the menu button
        `items` - The items to display in the popup menu.
      Since:
        JavaFX 8u40

  - ### Method Detail

    - #### isShowing

          public final boolean isShowing()

      Gets the value of the property showing.
      Property description:
        Indicates whether the `ContextMenu` is currently visible.
      Default value:
        false

    - #### showingProperty

          public final ReadOnlyBooleanProperty showingProperty()

      Indicates whether the `ContextMenu` is currently visible.
      Default value:
        false
      See Also:
        `isShowing()`

    - #### onShowingProperty

          public final ObjectProperty<EventHandler<Event>> onShowingProperty()

      Called just prior to the `ContextMenu` being shown, even if the menu has no items to show. Note however that this won't be called if the menu does not have a valid anchor node.
      See Also:
        `getOnShowing()`, `setOnShowing(EventHandler)`

    - #### setOnShowing

          public final void setOnShowing​(EventHandler<Event> value)

      Sets the value of the property onShowing.
      Property description:
        Called just prior to the `ContextMenu` being shown, even if the menu has no items to show. Note however that this won't be called if the menu does not have a valid anchor node.

    - #### getOnShowing

          public final EventHandler<Event> getOnShowing()

      Gets the value of the property onShowing.
      Property description:
        Called just prior to the `ContextMenu` being shown, even if the menu has no items to show. Note however that this won't be called if the menu does not have a valid anchor node.

    - #### onShownProperty

          public final ObjectProperty<EventHandler<Event>> onShownProperty()

      Called just after the `ContextMenu` is shown.
      See Also:
        `getOnShown()`, `setOnShown(EventHandler)`

    - #### setOnShown

          public final void setOnShown​(EventHandler<Event> value)

      Sets the value of the property onShown.
      Property description:
        Called just after the `ContextMenu` is shown.

    - #### getOnShown

          public final EventHandler<Event> getOnShown()

      Gets the value of the property onShown.
      Property description:
        Called just after the `ContextMenu` is shown.

    - #### onHidingProperty

          public final ObjectProperty<EventHandler<Event>> onHidingProperty()

      Called just prior to the `ContextMenu` being hidden.
      See Also:
        `getOnHiding()`, `setOnHiding(EventHandler)`

    - #### setOnHiding

          public final void setOnHiding​(EventHandler<Event> value)

      Sets the value of the property onHiding.
      Property description:
        Called just prior to the `ContextMenu` being hidden.

    - #### getOnHiding

          public final EventHandler<Event> getOnHiding()

      Gets the value of the property onHiding.
      Property description:
        Called just prior to the `ContextMenu` being hidden.

    - #### onHiddenProperty

          public final ObjectProperty<EventHandler<Event>> onHiddenProperty()

      Called just after the `ContextMenu` has been hidden.
      See Also:
        `getOnHidden()`, `setOnHidden(EventHandler)`

    - #### setOnHidden

          public final void setOnHidden​(EventHandler<Event> value)

      Sets the value of the property onHidden.
      Property description:
        Called just after the `ContextMenu` has been hidden.

    - #### getOnHidden

          public final EventHandler<Event> getOnHidden()

      Gets the value of the property onHidden.
      Property description:
        Called just after the `ContextMenu` has been hidden.

    - #### getItems

          public final ObservableList<MenuItem> getItems()

      The items to show within this menu. If this ObservableList is modified at runtime, the Menu will update as expected.
      Returns:
        the list of items

    - #### show

          public void show()

      If the Menu is not disabled and the `ContextMenu` is not already showing, then this will cause the `ContextMenu` to be shown.

    - #### hide

          public void hide()

      Hides the `ContextMenu` if it was previously showing, and any showing submenus. If this menu is not showing, then invoking this function has no effect.

    - #### addEventHandler

          public <E extends Event> void addEventHandler​(EventType<E> eventType,
                                                        EventHandler<E> eventHandler)

      Registers an event handler to this MenuItem. The handler is called when the menu item receives an `Event` of the specified type during the bubbling phase of event delivery.
      Overrides:
        `addEventHandler` in class `MenuItem`
      Type Parameters:
        `E` - the specific event class of the handler
      Parameters:
        `eventType` - the type of the events to receive by the handler
        `eventHandler` - the handler to register

    - #### removeEventHandler

          public <E extends Event> void removeEventHandler​(EventType<E> eventType,
                                                           EventHandler<E> eventHandler)

      Unregisters a previously registered event handler from this MenuItem. One handler might have been registered for different event types, so the caller needs to specify the particular event type from which to unregister the handler.
      Overrides:
        `removeEventHandler` in class `MenuItem`
      Type Parameters:
        `E` - the specific event class of the handler
      Parameters:
        `eventType` - the event type from which to unregister
        `eventHandler` - the handler to unregister

    - #### buildEventDispatchChain

          public EventDispatchChain buildEventDispatchChain​(EventDispatchChain tail)

      Construct an event dispatch chain for this target. The event dispatch chain contains event dispatchers which might be interested in processing of events targeted at this `EventTarget`. This event target is not automatically added to the chain, so if it wants to process events, it needs to add an `EventDispatcher` for itself to the chain.

      In the case the event target is part of some hierarchy, the chain for it is usually built from event dispatchers collected from the root of the hierarchy to the event target.

      The event dispatch chain is constructed by modifications to the provided initial event dispatch chain. The returned chain should have the initial chain at its end so the dispatchers should be prepended to the initial chain.

      The caller shouldn't assume that the initial chain remains unchanged nor that the returned value will reference a different chain.

      Specified by:
        `buildEventDispatchChain` in interface `EventTarget`
      Overrides:
        `buildEventDispatchChain` in class `MenuItem`
      Parameters:
        `tail` - the initial chain to build from
      Returns:
        the resulting event dispatch chain for this target