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

Class MenuCombo

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.FlowPanel

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

All Implemented Interfaces:

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.InsertPanel, com.google.gwt.user.client.ui.InsertPanel.ForIsWidget, com.google.gwt.user.client.ui.IsWidget, Iterable<com.google.gwt.user.client.ui.Widget>

public class MenuCombo
extends com.google.gwt.user.client.ui.FlowPanel
implements IMenu

MenuCombo makes it simpler and safer to build Menus. It absorbs the complexity of creating a Menu and its related action Button. In fact, for the Menu to work properly some requirements must be satisfied. With mdl, these requirement are the responsibility of the developer. This component's goal is to encapsulate these requirements and to hide them from the developer. By enforcing these rules inside the menu, the developer's full attention goes to the application logic. These requirements are as follows :

1. The Button should be created first and then added to the DOM before the Menu is. Otherwise, the Menu won't be able to attach its event handlers to it.
2. The menu should live inside the same element as the its action Button.
3. The Menu should reference the id of its related Button in order for mdl to bind them together. The developer should provide an id for the Button which should then be fed to the Menu. Button.

Author:

Mohamed Ilyes DIMASSI

Nested Class Summary

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.InsertPanel

com.google.gwt.user.client.ui.InsertPanel.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
MenuCombo(Button btn) Setup a MenuCombo.

Method Summary

Methods

Modifier and Type	Method and Description
void	addItem(String item, boolean enabled) Has the same effect as MenuCombo.addItem(item , item, enabled).
void	addItem(String text, String value, boolean enabled) Adds a new option to the list of options in the menu.
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 .
void	clearMenu() Remove all items from the menu.
int	getItemCount() Returns the items count in a menu.
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.
void	setAnchor(MenuAnchor anchor) 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.
boolean	setEnabled(int index, boolean enabled) Modify the enabled state of an item.

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

add, clear, insert, insert

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

add, 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, 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, onLoad, 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.InsertPanel.ForIsWidget

add

Methods inherited from interface com.google.gwt.user.client.ui.IndexedPanel.ForIsWidget

getWidgetIndex

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

getWidget, getWidgetCount, getWidgetIndex, remove

Constructor Detail

MenuCombo

public MenuCombo(Button btn)

Setup a MenuCombo.

A menu combo is made of a Button and a Menu that works together to display the menu to the user when the button is clicked. Using this constructor, the user provides the instance of the button. The menu property is managed behind the scene at the combo.

Parameters:

btn - the action button for the menu

Method Detail

setAnchor

public final void setAnchor(MenuAnchor anchor)

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:

anchor - the requested Anchor position for the Menu .

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 final void addItem(String item,
           boolean enabled)

Has the same effect as MenuCombo.addItem(item , item, enabled).

Parameters:

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

enabled - the state 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 Menu.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.