/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.user.client.ui;
import com.google.gwt.safehtml.client.HasSafeHtml;
import com.google.gwt.safehtml.shared.SafeHtml;
import com.google.gwt.user.client.Command;
import com.google.gwt.user.client.DOM;
/**
* An entry in a
* {@link com.google.gwt.user.client.ui.MenuBar}. Menu items can either fire a
* {@link com.google.gwt.user.client.Command} when they are clicked, or open a
* cascading sub-menu.
*
* Each menu item is assigned a unique DOM id in order to support ARIA. See
* {@link com.google.gwt.user.client.ui.Accessibility} for more information.
*/
public class MenuItem extends UIObject implements HasHTML, HasEnabled, HasSafeHtml {
private static final String DEPENDENT_STYLENAME_SELECTED_ITEM = "selected";
private static final String DEPENDENT_STYLENAME_DISABLED_ITEM = "disabled";
private Command command;
private MenuBar parentMenu, subMenu;
private boolean enabled = true;
/**
* Constructs a new menu item that fires a command when it is selected.
*
* @param html the item's html text
*/
public MenuItem(SafeHtml html) {
this(html.asString(), true);
}
/**
* Constructs a new menu item that fires a command when it is selected.
*
* @param html the item's text
* @param cmd the command to be fired when it is selected
*/
public MenuItem(SafeHtml html, Command cmd) {
this(html.asString(), true, cmd);
}
/**
* Constructs a new menu item that cascades to a sub-menu when it is selected.
*
* @param html the item's text
* @param subMenu the sub-menu to be displayed when it is selected
*/
public MenuItem(SafeHtml html, MenuBar subMenu) {
this(html.asString(), true, subMenu);
}
/**
* Constructs a new menu item that fires a command when it is selected.
*
* @param text the item's text
* @param asHTML <code>true</code> to treat the specified text as html
* @param cmd the command to be fired when it is selected
*/
public MenuItem(String text, boolean asHTML, Command cmd) {
this(text, asHTML);
setCommand(cmd);
}
/**
* Constructs a new menu item that cascades to a sub-menu when it is selected.
*
* @param text the item's text
* @param asHTML <code>true</code> to treat the specified text as html
* @param subMenu the sub-menu to be displayed when it is selected
*/
public MenuItem(String text, boolean asHTML, MenuBar subMenu) {
this(text, asHTML);
setSubMenu(subMenu);
}
/**
* Constructs a new menu item that fires a command when it is selected.
*
* @param text the item's text
* @param cmd the command to be fired when it is selected
*/
public MenuItem(String text, Command cmd) {
this(text, false);
setCommand(cmd);
}
/**
* Constructs a new menu item that cascades to a sub-menu when it is selected.
*
* @param text the item's text
* @param subMenu the sub-menu to be displayed when it is selected
*/
public MenuItem(String text, MenuBar subMenu) {
this(text, false);
setSubMenu(subMenu);
}
MenuItem(String text, boolean asHTML) {
setElement(DOM.createTD());
setSelectionStyle(false);
if (asHTML) {
setHTML(text);
} else {
setText(text);
}
setStyleName("gwt-MenuItem");
DOM.setElementAttribute(getElement(), "id", DOM.createUniqueId());
// Add a11y role "menuitem"
Accessibility.setRole(getElement(), Accessibility.ROLE_MENUITEM);
}
/**
* Gets the command associated with this item.
*
* @return this item's command, or <code>null</code> if none exists
*/
public Command getCommand() {
return command;
}
public String getHTML() {
return DOM.getInnerHTML(getElement());
}
/**
* Gets the menu that contains this item.
*
* @return the parent menu, or <code>null</code> if none exists.
*/
public MenuBar getParentMenu() {
return parentMenu;
}
/**
* Gets the sub-menu associated with this item.
*
* @return this item's sub-menu, or <code>null</code> if none exists
*/
public MenuBar getSubMenu() {
return subMenu;
}
public String getText() {
return DOM.getInnerText(getElement());
}
public boolean isEnabled() {
return enabled;
}
/**
* Sets the command associated with this item.
*
* @param cmd the command to be associated with this item
*/
public void setCommand(Command cmd) {
command = cmd;
}
public void setEnabled(boolean enabled) {
if (enabled) {
removeStyleDependentName(DEPENDENT_STYLENAME_DISABLED_ITEM);
} else {
addStyleDependentName(DEPENDENT_STYLENAME_DISABLED_ITEM);
}
this.enabled = enabled;
}
public void setHTML(SafeHtml html) {
setHTML(html.asString());
}
public void setHTML(String html) {
DOM.setInnerHTML(getElement(), html);
}
/**
* Sets the sub-menu associated with this item.
*
* @param subMenu this item's new sub-menu
*/
public void setSubMenu(MenuBar subMenu) {
this.subMenu = subMenu;
if (this.parentMenu != null) {
this.parentMenu.updateSubmenuIcon(this);
}
if (subMenu != null) {
// Change tab index from 0 to -1, because only the root menu is supposed
// to be in the tab order
FocusPanel.impl.setTabIndex(subMenu.getElement(), -1);
// Update a11y role "haspopup"
Accessibility.setState(this.getElement(), Accessibility.STATE_HASPOPUP,
"true");
} else {
// Update a11y role "haspopup"
Accessibility.setState(this.getElement(), Accessibility.STATE_HASPOPUP,
"false");
}
}
public void setText(String text) {
DOM.setInnerText(getElement(), text);
}
/**
* Also sets the Debug IDs of MenuItems in the submenu of this
* {@link MenuItem} if a submenu exists.
*
* @see UIObject#onEnsureDebugId(String)
*/
@Override
protected void onEnsureDebugId(String baseID) {
super.onEnsureDebugId(baseID);
if (subMenu != null) {
subMenu.setMenuItemDebugIds(baseID);
}
}
protected void setSelectionStyle(boolean selected) {
if (selected) {
addStyleDependentName(DEPENDENT_STYLENAME_SELECTED_ITEM);
} else {
removeStyleDependentName(DEPENDENT_STYLENAME_SELECTED_ITEM);
}
}
void setParentMenu(MenuBar parentMenu) {
this.parentMenu = parentMenu;
}
}