Java tutorial
/** * Sencha GXT 4.0.0 - Sencha for GWT * Copyright (c) 2006-2015, Sencha Inc. * * licensing@sencha.com * http://www.sencha.com/products/gxt/license/ * * ================================================================================ * Open Source License * ================================================================================ * This version of Sencha GXT is licensed under the terms of the Open Source GPL v3 * license. You may use this license only if you are prepared to distribute and * share the source code of your application under the GPL v3 license: * http://www.gnu.org/licenses/gpl.html * * If you are NOT prepared to distribute and share the source code of your * application under the GPL v3 license, other commercial and oem licenses * are available for an alternate download of Sencha GXT. * * Please see the Sencha GXT Licensing page at: * http://www.sencha.com/products/gxt/license/ * * For clarification or additional options, please contact: * licensing@sencha.com * ================================================================================ * * * ================================================================================ * Disclaimer * ================================================================================ * THIS SOFTWARE IS DISTRIBUTED "AS-IS" WITHOUT ANY WARRANTIES, CONDITIONS AND * REPRESENTATIONS WHETHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE * IMPLIED WARRANTIES AND CONDITIONS OF MERCHANTABILITY, MERCHANTABLE QUALITY, * FITNESS FOR A PARTICULAR PURPOSE, DURABILITY, NON-INFRINGEMENT, PERFORMANCE AND * THOSE ARISING BY STATUTE OR FROM CUSTOM OR USAGE OF TRADE OR COURSE OF DEALING. * ================================================================================ */ package com.sencha.gxt.widget.core.client.menu; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Element; import com.google.gwt.dom.client.EventTarget; import com.google.gwt.dom.client.NativeEvent; import com.google.gwt.event.dom.client.KeyCodes; import com.google.gwt.safehtml.shared.SafeHtmlBuilder; import com.google.gwt.user.client.Event; import com.google.gwt.user.client.ui.Widget; import com.sencha.gxt.core.client.GXT; import com.sencha.gxt.core.client.Style.Anchor; import com.sencha.gxt.core.client.Style.AnchorAlignment; import com.sencha.gxt.core.client.dom.XDOM; import com.sencha.gxt.core.client.gestures.TapGestureRecognizer; import com.sencha.gxt.core.client.gestures.TouchData; import com.sencha.gxt.core.client.util.KeyNav; import com.sencha.gxt.widget.core.client.container.InsertContainer; import com.sencha.gxt.widget.core.client.event.HideEvent; import com.sencha.gxt.widget.core.client.event.HideEvent.HideHandler; import com.sencha.gxt.widget.core.client.event.MaximizeEvent; import com.sencha.gxt.widget.core.client.event.MaximizeEvent.MaximizeHandler; import com.sencha.gxt.widget.core.client.event.MinimizeEvent; import com.sencha.gxt.widget.core.client.event.MinimizeEvent.MinimizeHandler; public class MenuBar extends InsertContainer { public static interface MenuBarAppearance { void render(SafeHtmlBuilder builder); } class Handler implements HideHandler, MaximizeHandler, MinimizeHandler { @Override public void onHide(HideEvent event) { autoSelect = false; autoSelect = true; if (active != null) active.expanded = false; } @Override public void onMaximize(MaximizeEvent event) { int index = getWidgetIndex(active); index = index != getWidgetCount() - 1 ? index + 1 : 0; MenuBarItem item = (MenuBarItem) getWidget(index); setActiveItem(item, true); } @Override public void onMinimize(MinimizeEvent event) { int index = getWidgetIndex(active); index = index > 0 ? index - 1 : getWidgetCount() - 1; MenuBarItem item = (MenuBarItem) getWidget(index); setActiveItem(item, true); } } protected MenuBarItem active; private final MenuBarAppearance appearance; private boolean autoSelect = true; private Handler handler = new Handler(); public MenuBar() { this(GWT.<MenuBarAppearance>create(MenuBarAppearance.class)); } public MenuBar(MenuBarAppearance appearance) { this.appearance = appearance; SafeHtmlBuilder builder = new SafeHtmlBuilder(); appearance.render(builder); setElement((Element) XDOM.create(builder.toSafeHtml())); sinkEvents(Event.ONCLICK | Event.MOUSEEVENTS | Event.ONFOCUS | Event.ONBLUR); getElement().setTabIndex(-1); getElement().setAttribute("hideFocus", "true"); new KeyNav(this) { @Override public void onKeyPress(NativeEvent evt) { MenuBar.this.onKeyPress(evt); } }; // Ignore Menu preview event hiding menubar when toggle click occurs. addStyleName("x-ignore"); addGestureRecognizer(new TapGestureRecognizer() { @Override public boolean handleEnd(NativeEvent endEvent) { super.handleEnd(endEvent); onClick(endEvent.<Event>cast()); return true; } }); } public MenuBarAppearance getAppearance() { return appearance; } @Override public void onBrowserEvent(Event event) { super.onBrowserEvent(event); switch (event.getTypeInt()) { case Event.ONCLICK: onClick(event); break; case Event.ONMOUSEOVER: onMouseOver(event); break; case Event.ONMOUSEOUT: onMouseOut(event); break; case Event.ONFOCUS: if (autoSelect && active == null && getWidgetCount() > 0) { setActiveItem((MenuBarItem) getWidget(0), false); } break; case Event.ONBLUR: if (active != null && !active.expanded) { onDeactivate(active); } break; } } /** * Sets the active item. * * @param item the item to activate * @param expand true to expand the item's menu */ public void setActiveItem(final MenuBarItem item, boolean expand) { // shouldn't automatically select first item on touch since it disables that item from being selected setActiveItem(item, expand, !GXT.isTouch()); } /** * Sets the active item. * * @param item the item to activate * @param expand true to expand the item's menu * @param selectFirst sets the first item enabled or disabled */ public void setActiveItem(final MenuBarItem item, boolean expand, boolean selectFirst) { if (active != item) { if (active != null) { onDeactivate(active); } onActivate(item); if (expand) { expand(item, selectFirst); } } } /** * Toggles the given item. * * @param item the item to toggle */ public void toggle(MenuBarItem item) { if (item == active) { if (item.expanded) { collapse(item); } else { expand(item, false); } } else { setActiveItem(item, true); } } protected void collapse(MenuBarItem item) { item.menu.hide(); item.expanded = false; } protected void expand(MenuBarItem item, boolean selectFirst) { item.menu.setOnHideFocusElement(getFocusEl()); item.menu.setFocusOnShow(false); item.menu.show(item.getElement(), new AnchorAlignment(Anchor.TOP_LEFT, Anchor.BOTTOM_LEFT), 0, 1); item.expanded = true; if (item.menu.getWidgetCount() > 0 && selectFirst) { item.menu.setActiveItem(item.menu.getWidget(0), false); } } protected void onActivate(MenuBarItem item) { active = item; // Accessibility.setState(getElement(), "aria-activedescendant", // item.getId()); item.getAppearance().onActive(item.getElement(), true); // item.addStyleName(item.getBaseStyle() + "-active"); // item.addStyleName(item.getBaseStyle() + "-over"); } protected void onClick(Event event) { event.stopPropagation(); event.preventDefault(); MenuBarItem item = (MenuBarItem) findWidget(event.getEventTarget().<Element>cast()); if (item != null) { toggle(item); } } protected void onDeactivate(MenuBarItem item) { if (item.expanded) { item.menu.hide(); item.expanded = false; } item.getAppearance().onActive(item.getElement(), false); item.getAppearance().onOver(item.getElement(), false); // item.removeStyleName(item.getBaseStyle() + "-active"); // item.removeStyleName(item.getBaseStyle() + "-over"); // if (GXT.isFocusManagerEnabled()) { // FocusFrame.get().unframe(); // } if (active == item) { active = null; } } protected void onDown(NativeEvent event) { if (active != null && getWidgetCount() > 0) { event.preventDefault(); event.stopPropagation(); if (active.expanded) { active.menu.focus(); active.menu.setActiveItem(active.menu.getWidget(0), false); } else { expand(active, true); } } } @Override protected void onInsert(int index, Widget child) { super.onInsert(index, child); MenuBarItem item = (MenuBarItem) child; Menu itemMenu = item.getMenu(); itemMenu.addHideHandler(handler); itemMenu.addMaximizeHandler(handler); itemMenu.addMinimizeHandler(handler); } protected void onKeyPress(NativeEvent evt) { switch (evt.getKeyCode()) { case KeyCodes.KEY_DOWN: onDown(evt); break; case KeyCodes.KEY_LEFT: onLeft(evt); break; case KeyCodes.KEY_RIGHT: onRight(evt); break; } } protected void onLeft(NativeEvent event) { if (active != null && getWidgetCount() > 1) { int idx = getWidgetIndex(active); idx = idx != 0 ? idx - 1 : getWidgetCount() - 1; MenuBarItem item = (MenuBarItem) getWidget(idx); setActiveItem(item, true, true); } } protected void onMouseOut(Event event) { EventTarget eventTarget = event.getEventTarget(); if ((eventTarget == null || (Element.is(eventTarget) && findWidget((Element) Element.as(eventTarget)) == null)) && active != null && !active.expanded) { onDeactivate(active); } } protected void onMouseOver(Event event) { EventTarget eventTarget = event.getEventTarget(); if (eventTarget != null) { Element element = eventTarget.<Element>cast(); if (element != null) { MenuBarItem item = (MenuBarItem) findWidget(element); if (item != null && item != active) { setActiveItem(item, active != null && active.expanded, false); } } } } protected void onRight(NativeEvent event) { if (active != null && getWidgetCount() > 1) { int idx = getWidgetIndex(active); idx = idx != getWidgetCount() - 1 ? idx + 1 : 0; MenuBarItem item = (MenuBarItem) getWidget(idx); setActiveItem(item, true, true); } } }