Java tutorial
/* * Copyright 2000-2018 Vaadin Ltd. * * 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.vaadin.client.ui.menubar; import java.util.Iterator; import java.util.Stack; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Element; import com.google.gwt.user.client.Command; import com.google.gwt.user.client.Timer; import com.vaadin.client.ApplicationConnection; import com.vaadin.client.Paintable; import com.vaadin.client.TooltipInfo; import com.vaadin.client.UIDL; import com.vaadin.client.annotations.OnStateChange; import com.vaadin.client.ui.AbstractComponentConnector; import com.vaadin.client.ui.Icon; import com.vaadin.client.ui.SimpleManagedLayout; import com.vaadin.client.ui.VMenuBar; import com.vaadin.shared.ui.ComponentStateUtil; import com.vaadin.shared.ui.Connect; import com.vaadin.shared.ui.menubar.MenuBarConstants; import com.vaadin.shared.ui.menubar.MenuBarState; @Connect(com.vaadin.ui.MenuBar.class) public class MenuBarConnector extends AbstractComponentConnector implements Paintable, SimpleManagedLayout { /** * This method must be implemented to update the client-side component from * UIDL data received from server. * * This method is called when the page is loaded for the first time, and * every time UI changes in the component are received from the server. */ @Override public void updateFromUIDL(UIDL uidl, ApplicationConnection client) { if (!isRealUpdate(uidl)) { return; } VMenuBar widget = getWidget(); widget.htmlContentAllowed = uidl.hasAttribute(MenuBarConstants.HTML_CONTENT_ALLOWED); widget.openRootOnHover = uidl.getBooleanAttribute(MenuBarConstants.OPEN_ROOT_MENU_ON_HOWER); widget.enabled = isEnabled(); // For future connections widget.client = client; widget.uidlId = uidl.getId(); Timer timer = new Timer() { @Override public void run() { // Empty the menu every time it receives new information if (!widget.getItems().isEmpty()) { widget.clearItems(); } UIDL options = uidl.getChildUIDL(0); if (null != getState() && !ComponentStateUtil.isUndefinedWidth(getState())) { UIDL moreItemUIDL = options.getChildUIDL(0); StringBuilder itemHTML = new StringBuilder(); if (moreItemUIDL.hasAttribute("icon")) { Icon icon = client.getIcon(moreItemUIDL.getStringAttribute("icon")); if (icon != null) { itemHTML.append(icon.getElement().getString()); } } String moreItemText = moreItemUIDL.getStringAttribute("text"); if ("".equals(moreItemText)) { moreItemText = "►"; } itemHTML.append(moreItemText); widget.moreItem = GWT.create(VMenuBar.CustomMenuItem.class); widget.moreItem.setHTML(itemHTML.toString()); widget.moreItem.setCommand(VMenuBar.emptyCommand); widget.collapsedRootItems = new VMenuBar(true, widget); widget.moreItem.setSubMenu(widget.collapsedRootItems); widget.moreItem.addStyleName(widget.getStylePrimaryName() + "-more-menuitem"); } UIDL uidlItems = uidl.getChildUIDL(1); Iterator<Object> itr = uidlItems.iterator(); Stack<Iterator<Object>> iteratorStack = new Stack<>(); Stack<VMenuBar> menuStack = new Stack<>(); VMenuBar currentMenu = widget; while (itr.hasNext()) { UIDL item = (UIDL) itr.next(); VMenuBar.CustomMenuItem currentItem = null; final int itemId = item.getIntAttribute("id"); boolean itemHasCommand = item.hasAttribute("command"); boolean itemIsCheckable = item.hasAttribute(MenuBarConstants.ATTRIBUTE_CHECKED); String itemHTML = widget.buildItemHTML(item); Command cmd = null; if (!item.hasAttribute("separator")) { if (itemHasCommand || itemIsCheckable) { // Construct a command that fires onMenuClick(int) // with the // item's id-number cmd = () -> widget.hostReference.onMenuClick(itemId); } } currentItem = currentMenu.addItem(itemHTML, cmd); currentItem.setId("" + itemId); currentItem.updateFromUIDL(item, client); if (item.getChildCount() > 0) { menuStack.push(currentMenu); iteratorStack.push(itr); itr = item.iterator(); currentMenu = new VMenuBar(true, currentMenu); client.getVTooltip().connectHandlersToWidget(currentMenu); // this is the top-level style that also propagates to // items - // any item specific styles are set above in // currentItem.updateFromUIDL(item, client) if (ComponentStateUtil.hasStyles(getState())) { for (String style : getState().styles) { currentMenu.addStyleDependentName(style); } } currentItem.setSubMenu(currentMenu); } while (!itr.hasNext() && !iteratorStack.empty()) { boolean hasCheckableItem = false; for (VMenuBar.CustomMenuItem menuItem : currentMenu.getItems()) { hasCheckableItem = hasCheckableItem || menuItem.isCheckable(); } if (hasCheckableItem) { currentMenu.addStyleDependentName("check-column"); } else { currentMenu.removeStyleDependentName("check-column"); } itr = iteratorStack.pop(); currentMenu = menuStack.pop(); } } } }; getLayoutManager().setNeedsHorizontalLayout(MenuBarConnector.this); if (widget.mouseDownPressed) { timer.schedule(getState().delayMs); widget.mouseDownPressed = false; } else { timer.run(); } } @Override public VMenuBar getWidget() { return (VMenuBar) super.getWidget(); } @Override public MenuBarState getState() { return (MenuBarState) super.getState(); } @Override public void layout() { getWidget().iLayout(); } @Override public TooltipInfo getTooltipInfo(Element element) { TooltipInfo info = null; // Check content of widget to find tooltip for element if (element != getWidget().getElement()) { VMenuBar.CustomMenuItem item = getWidget().getMenuItemWithElement(element); if (item != null) { info = item.getTooltip(); } } // Use default tooltip if nothing found from DOM three if (info == null) { info = super.getTooltipInfo(element); } return info; } @Override public boolean hasTooltip() { /* * Item tooltips are not processed until updateFromUIDL, so we can't be * sure that there are no tooltips during onStateChange when this method * is used. */ return true; } @OnStateChange("enabled") void updateEnabled() { if (getState().enabled) { getWidget().getElement().removeAttribute("aria-disabled"); } else { getWidget().getElement().setAttribute("aria-disabled", "true"); } } @OnStateChange("tabIndex") void updateTabIndex() { getWidget().getElement().setAttribute("tabindex", String.valueOf(getState().tabIndex)); } }