Java tutorial
/* * Copyright 2000-2014 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; import java.util.logging.Logger; import com.google.gwt.aria.client.Roles; import com.google.gwt.core.client.GWT; import com.google.gwt.dom.client.Element; import com.google.gwt.event.logical.shared.CloseHandler; import com.google.gwt.user.client.DOM; import com.google.gwt.user.client.ui.PopupPanel; import com.google.gwt.user.client.ui.RootPanel; import com.vaadin.client.ApplicationConnection; import com.vaadin.client.ComponentConnector; import com.vaadin.client.Util; import com.vaadin.client.widgets.Overlay; /** * In Vaadin UI this VOverlay should always be used for all elements that * temporary float over other components like context menus etc. This is to deal * stacking order correctly with VWindow objects. * <p> * To use this correctly, use {@link GWT#create(Class)} to create the * {@link Overlay} superclass and the default widgetset will replace it with * this. The widget will not be dependent on this Vaadin specific widget and can * be used in a pure GWT environment. * * @deprecated as this is specifically for Vaadin only, it should not be used * directly. */ @Deprecated public class VOverlay extends Overlay implements CloseHandler<PopupPanel> { /* * ApplicationConnection that this overlay belongs to, which is needed to * create the overlay in the correct container so that the correct styles * are applied. If not given, owner will be used to figure out, and as a * last fallback, the overlay is created w/o container, potentially missing * styles. */ protected ApplicationConnection ac; public VOverlay() { super(); } public VOverlay(boolean autoHide) { super(autoHide); } public VOverlay(boolean autoHide, boolean modal) { super(autoHide, modal); } /** * @deprecated See main JavaDoc for VOverlay. Use the other constructors * without the <code>showShadow</code> parameter. */ @Deprecated public VOverlay(boolean autoHide, boolean modal, boolean showShadow) { super(autoHide, modal, showShadow); } /* * A "thread local" of sorts, set temporarily so that VOverlayImpl knows * which VOverlay is using it, so that it can be attached to the correct * overlay container. * * TODO this is a strange pattern that we should get rid of when possible. */ protected static VOverlay current; /** * Get the {@link ApplicationConnection} that this overlay belongs to. If * it's not set, {@link #getOwner()} is used to figure it out. * * @return */ protected ApplicationConnection getApplicationConnection() { if (ac != null) { return ac; } else if (getOwner() != null) { ComponentConnector c = Util.findConnectorFor(getOwner()); if (c != null) { ac = c.getConnection(); } return ac; } else { return null; } } /** * Gets the 'overlay container' element. Tries to find the current * {@link ApplicationConnection} using {@link #getApplicationConnection()}. * * @return the overlay container element for the current * {@link ApplicationConnection} or another element if the current * {@link ApplicationConnection} cannot be determined. */ @Override public com.google.gwt.user.client.Element getOverlayContainer() { ApplicationConnection ac = getApplicationConnection(); if (ac == null) { // could not figure out which one we belong to, styling will // probably fail Logger.getLogger(getClass().getSimpleName()).warning( "Could not determine ApplicationConnection for Overlay. Overlay will be attached directly to the root panel"); return super.getOverlayContainer(); } else { return getOverlayContainer(ac); } } /** * Gets the 'overlay container' element pertaining to the given * {@link ApplicationConnection}. Each overlay should be created in a * overlay container element, so that the correct theme and styles can be * applied. * * @param ac * A reference to {@link ApplicationConnection} * @return The overlay container */ public static com.google.gwt.user.client.Element getOverlayContainer(ApplicationConnection ac) { String id = ac.getConfiguration().getRootPanelId(); id = id += "-overlays"; Element container = DOM.getElementById(id); if (container == null) { container = DOM.createDiv(); container.setId(id); String styles = ac.getUIConnector().getWidget().getParent().getStyleName(); if (styles != null && !styles.equals("")) { container.addClassName(styles); } container.addClassName(CLASSNAME_CONTAINER); RootPanel.get().getElement().appendChild(container); } return DOM.asOld(container); } /** * Set the label of the container element, where tooltip, notification and * dialgs are added to. * * @param applicationConnection * the application connection for which to change the label * @param overlayContainerLabel * label for the container */ public static void setOverlayContainerLabel(ApplicationConnection applicationConnection, String overlayContainerLabel) { Roles.getAlertRole().setAriaLabelProperty(VOverlay.getOverlayContainer(applicationConnection), overlayContainerLabel); } }