com.github.ilyes4j.gwt.mdl.components.menus

Class Menu

java.lang.Object

com.google.gwt.user.client.ui.UIObject

com.google.gwt.user.client.ui.Widget

com.google.gwt.user.client.ui.Panel

com.google.gwt.user.client.ui.ComplexPanel

com.google.gwt.user.client.ui.HTMLPanel

com.github.ilyes4j.gwt.mdl.components.menus.Menu

All Implemented Interfaces:

IUpgrade, IHasEventSource, IMenu, com.google.gwt.event.logical.shared.HasAttachHandlers, com.google.gwt.event.shared.HasHandlers, com.google.gwt.user.client.EventListener, com.google.gwt.user.client.ui.HasVisibility, com.google.gwt.user.client.ui.HasWidgets, com.google.gwt.user.client.ui.HasWidgets.ForIsWidget, com.google.gwt.user.client.ui.IndexedPanel, com.google.gwt.user.client.ui.IndexedPanel.ForIsWidget, com.google.gwt.user.client.ui.IsWidget, Iterable<com.google.gwt.user.client.ui.Widget>

public class Menu
extends com.google.gwt.user.client.ui.HTMLPanel
implements IMenu, IHasEventSource

A Menu is a wrapper for the MaterialMenu component. It enables the user to select an option from a list of items presented in a dialog. It is activated when its associated button is clicked.

Author:

Mohamed Ilyes DIMASSI

See Also:

Button

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	Menu.ItemClickListener Objects that need to be notified when an MenuItem is clicked should implement this interface and register themselves to the Menu using the addItemClickListener(ItemClickListener) method.

Nested classes/interfaces inherited from class com.google.gwt.user.client.ui.UIObject

com.google.gwt.user.client.ui.UIObject.DebugIdImpl, com.google.gwt.user.client.ui.UIObject.DebugIdImplEnabled

Nested classes/interfaces inherited from interface com.google.gwt.user.client.ui.IndexedPanel

com.google.gwt.user.client.ui.IndexedPanel.ForIsWidget

Nested classes/interfaces inherited from interface com.google.gwt.user.client.ui.HasWidgets

com.google.gwt.user.client.ui.HasWidgets.ForIsWidget

Field Summary

Fields inherited from class com.google.gwt.user.client.ui.UIObject

DEBUG_ID_PREFIX

Constructor Summary

Constructors

Constructor and Description
Menu() Creates the menu component and associates it with an action button.

Method Summary

Methods

Modifier and Type	Method and Description
void	addItem(String item) Has the same effect as Menu.addItem(item , true).
void	addItem(String item, boolean enabled) Syntactic sugar for IMenu.addItem(String, String, boolean) where the text and value are the same.
void	addItem(String value, String text) Shortcut for addItem(String, boolean) that adds an enabled item to the menu.
void	addItem(String text, String value, boolean enabled) Adds a new option to the list of options in the menu.
void	addItem(String text, String value, int position, boolean enabled) Adds a an option into the set of options of the menu at a specified position.
void	addItemClickListener(Menu.ItemClickListener listener) When an object needs to be notified upon a MenuItem click, it must be be registered to the Menu as an Menu.ItemClickListener . In order to receive item click notifications, the object should : Implement the Menu.ItemClickListener interface Define the actions that should be performed when a MenuItem is clicked inside Menu.ItemClickListener.onItemClicked(ItemClickEvent) Call addItemClickListener(ItemClickListener) to register itself to the menu and receive click notifications
protected void	afterItemClicked(com.google.gwt.event.dom.client.ClickEvent event) This method should be extended when additional behavior is required.
void	clearMenu() Remove all items from the menu.
int	getItemCount() Returns the items count in a menu.
protected List<MenuItem>	getItems() Getter for the items list.
String	getItemText(int index) return the text of the item located at the position provided as input.
String	getValue(int index) return the value of the item located at the position provided as input.
boolean	isEnabled(int index) Modify the enabled state of an item.
boolean	isUpgraded()
void	onLoad() Apply magic to bring the menu to life. After being attached to the DOM, the Menu is upgraded using ComponentHandler.upgradeElement(com.google.gwt.dom.client.Element) which in turn uses MaterialMenu to change the DOM tree of the component and add the required event handlers. The upgrade process performed by MaterialMenu requires the Menu to be already attached to the DOM.
void	removeItem(int index) Removes an item from the menu.
void	setActionId(String forId) Set the id of the related action Button enabling mdl to bind the Menu to it.
void	setAnchor(MenuAnchor inputAnchor) Sets the position of the Menu on the screen related to its associated action button using one of the available anchoring options provided by MenuAnchor. An extra care should be taken when anchoring the menu.
boolean	setEnabled(int index, boolean enabled) Modify the enabled state of an item.
void	setEventSource(Object inputSource)
protected void	setItems(List<MenuItem> itemList) Setter for the items list.
void	upgrade() Causes the component to be upgraded.

Methods inherited from class com.google.gwt.user.client.ui.HTMLPanel

add, add, add, addAndReplaceElement, addAndReplaceElement, addAndReplaceElement, addAndReplaceElement, addAndReplaceElement, addAndReplaceElement, createUniqueId, getElementById, wrap

Methods inherited from class com.google.gwt.user.client.ui.ComplexPanel

add, adjustIndex, checkIndexBoundsForAccess, checkIndexBoundsForInsertion, getChildren, getWidget, getWidgetCount, getWidgetIndex, getWidgetIndex, insert, insert, iterator, remove, remove

Methods inherited from class com.google.gwt.user.client.ui.Panel

add, adopt, clear, doAttachChildren, doDetachChildren, orphan, remove

Methods inherited from class com.google.gwt.user.client.ui.Widget

addAttachHandler, addBitlessDomHandler, addDomHandler, addHandler, asWidget, asWidgetOrNull, createHandlerManager, delegateEvent, fireEvent, getHandlerCount, getLayoutData, getParent, isAttached, isOrWasAttached, onAttach, onBrowserEvent, onDetach, onUnload, removeFromParent, setLayoutData, sinkEvents, unsinkEvents

Methods inherited from class com.google.gwt.user.client.ui.UIObject

addStyleDependentName, addStyleName, ensureDebugId, ensureDebugId, ensureDebugId, getAbsoluteLeft, getAbsoluteTop, getElement, getOffsetHeight, getOffsetWidth, getStyleElement, getStyleName, getStyleName, getStylePrimaryName, getStylePrimaryName, getTitle, isVisible, isVisible, onEnsureDebugId, removeStyleDependentName, removeStyleName, resolvePotentialElement, setElement, setElement, setHeight, setPixelSize, setSize, setStyleDependentName, setStyleName, setStyleName, setStyleName, setStyleName, setStylePrimaryName, setStylePrimaryName, setTitle, setVisible, setVisible, setWidth, sinkBitlessEvent, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.google.gwt.user.client.ui.IsWidget

asWidget

Constructor Detail

Menu

public Menu()

Creates the menu component and associates it with an action button. The link between the Menu and the action button is established by the id of the button and must be provided using setActionId(String).

When the menu is attached to the DOM, it will look for the action button using its id and will decorate it with the appropriate event handlers.

See Also:

Button

Method Detail

setEventSource

public void setEventSource(Object inputSource)

Specified by:

setEventSource in interface IHasEventSource

Parameters:

inputSource - the object designated as the source of events published by the menu

setActionId

public final void setActionId(String forId)
                       throws IllegalStateException

Set the id of the related action Button enabling mdl to bind the Menu to it. This method can only be invoked when the menu is not already attached to the DOM. If the menu is attached and therefore upgraded, the action button cannot be changed.

Parameters:

forId - The id of the action Button.

Throws:

IllegalStateException - mdl does not allow re binding the menu when the menu is not yet upgraded. If the menu is already upgraded an exception is raised.

setAnchor

public final void setAnchor(MenuAnchor inputAnchor)

Description copied from interface: IMenu

Sets the position of the Menu on the screen related to its associated action button using one of the available anchoring options provided by MenuAnchor.

An extra care should be taken when anchoring the menu. According to this thread , the menu's parent need a position:relative in order for the menu to be anchored correctly.

Specified by:

setAnchor in interface IMenu

Parameters:

inputAnchor - the requested Anchor position for the Menu

onLoad

public final void onLoad()

Apply magic to bring the menu to life.

After being attached to the DOM, the Menu is upgraded using ComponentHandler.upgradeElement(com.google.gwt.dom.client.Element) which in turn uses MaterialMenu to change the DOM tree of the component and add the required event handlers.

The upgrade process performed by MaterialMenu requires the Menu to be already attached to the DOM. This is due to the fact that MaterialMenu references the Menu's parent element during the upgrade.

When performing the upgrade, MaterialMenu will look for the associated button in the page DOM to attach the required events to it. That's why it is also mandatory that the related action button is attached to the DOM before Menu is.

Overrides:

onLoad in class com.google.gwt.user.client.ui.Widget

clearMenu

public final void clearMenu()

Description copied from interface: IMenu

Remove all items from the menu.

Specified by:

clearMenu in interface IMenu

addItem

public final void addItem(String text,
           String value,
           boolean enabled)

Description copied from interface: IMenu

Adds a new option to the list of options in the menu.

Specified by:

addItem in interface IMenu

Parameters:

text - The text to be displayed

value - The value to be added

enabled - Defines whether the option can be chosen or not.

addItem

public void addItem(String text,
           String value,
           int position,
           boolean enabled)

Description copied from interface: IMenu

Adds a an option into the set of options of the menu at a specified position.

Specified by:

addItem in interface IMenu

Parameters:

text - The text to be displayed

value - The value to be added

position - the insertion position of the item

enabled - Defines whether the option is available for selection.

addItem

public final void addItem(String item,
           boolean enabled)

Description copied from interface: IMenu

Syntactic sugar for IMenu.addItem(String, String, boolean) where the text and value are the same.

Specified by:

addItem in interface IMenu

Parameters:

item - The text to be displayed

enabled - Defines whether the option can be chosen or not.

addItem

public final void addItem(String item)

Has the same effect as Menu.addItem(item , true).

Parameters:

item - The value and the text of the item to be added

addItem

public final void addItem(String value,
           String text)

Shortcut for addItem(String, boolean) that adds an enabled item to the menu.

Parameters:

value - the value of the item to be added.

text - the text of the item to be added.

addItemClickListener

public final void addItemClickListener(Menu.ItemClickListener listener)

Description copied from interface: IMenu

When an object needs to be notified upon a MenuItem click, it must be be registered to the Menu as an Menu.ItemClickListener .

In order to receive item click notifications, the object should :

1. Implement the Menu.ItemClickListener interface
2. Define the actions that should be performed when a MenuItem is clicked inside Menu.ItemClickListener.onItemClicked(ItemClickEvent)
3. Call addItemClickListener(ItemClickListener) to register itself to the menu and receive click notifications

Specified by:

addItemClickListener in interface IMenu

Parameters:

listener - The object to be notified when a MenuItem is clicked.

See Also:

Menu.ItemClickListener

getItemCount

public final int getItemCount()

Description copied from interface: IMenu

Returns the items count in a menu.

Specified by:

getItemCount in interface IMenu

Returns:

the items count in a menu

getItemText

public final String getItemText(int index)

Description copied from interface: IMenu

return the text of the item located at the position provided as input.

Specified by:

getItemText in interface IMenu

Parameters:

index - the position of the item

Returns:

the text of the item at input position

getValue

public final String getValue(int index)

Description copied from interface: IMenu

return the value of the item located at the position provided as input.

Specified by:

getValue in interface IMenu

Parameters:

index - the position of the item

Returns:

the value of the item at input position

setEnabled

public final boolean setEnabled(int index,
                 boolean enabled)

Description copied from interface: IMenu

Modify the enabled state of an item. The position of the item is provided as input

Specified by:

setEnabled in interface IMenu

Parameters:

index - the position of the item in the item list of the menu

enabled - the state to be set for the item

Returns:

true if the state was modified, false otherwise.

isEnabled

public final boolean isEnabled(int index)

Description copied from interface: IMenu

Modify the enabled state of an item. The position of the item is provided as input

Specified by:

isEnabled in interface IMenu

Parameters:

index - the position of the item in the item list of the menu

Returns:

true if the item is enabled, false otherwise.

removeItem

public void removeItem(int index)

Description copied from interface: IMenu

Removes an item from the menu.

Specified by:

removeItem in interface IMenu

Parameters:

index - the position of the item to be removed

upgrade

public void upgrade()

Description copied from interface: IUpgrade

Causes the component to be upgraded.

Specified by:

upgrade in interface IUpgrade

isUpgraded

public boolean isUpgraded()

Specified by:

isUpgraded in interface IUpgrade

Returns:

the upgrade state of the component

afterItemClicked

protected void afterItemClicked(com.google.gwt.event.dom.client.ClickEvent event)

This method should be extended when additional behavior is required.

Parameters:

event - The browser click event.

setItems

protected final void setItems(List<MenuItem> itemList)

Setter for the items list.

Parameters:

itemList - the menu item list.

getItems

protected final List<MenuItem> getItems()

Getter for the items list.

Returns:

the menu item list.