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/** * Copyright (C) 2016 Red Hat, Inc. and/or its affiliates. * * 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 org.jboss.errai.common.client.dom; import java.util.Arrays; import java.util.Iterator; import java.util.NoSuchElementException; import java.util.Optional; import java.util.stream.Stream; import com.google.gwt.dom.client.Style; import com.google.gwt.user.client.ui.IsWidget; import com.google.gwt.user.client.ui.RootPanel; import com.google.gwt.user.client.ui.Widget; /** * Provides utility methods for interacting with the DOM. * * @deprecated Use Elemental 2 for new development * * @author Max Barkley <mbarkley@redhat.com> */ @Deprecated public abstract class DOMUtil { private DOMUtil() { } /** * @param element * Must not be null. * @return If the given element has any child elements, return an optional containing the first child element. * Otherwise return an empty optional. */ public static Optional<Element> getFirstChildElement(final Element element) { for (final Node child : nodeIterable(element.getChildNodes())) { if (isElement(child)) { return Optional.ofNullable((Element) child); } } return Optional.empty(); } /** * @param element * Must not be null. * @return If the given element has any child elements, return an optional containing the last child element. * Otherwise return an empty optional. */ public static Optional<Element> getLastChildElement(final Element element) { final NodeList children = element.getChildNodes(); for (int i = children.getLength() - 1; i > -1; i--) { if (isElement(children.item(i))) { return Optional.ofNullable((Element) children.item(i)); } } return Optional.empty(); } /** * @param node * Must not be null. * @return True iff the given node is an element. */ public static boolean isElement(final Node node) { return node.getNodeType() == Node.ELEMENT_NODE; } /** * @param nodeList * Must not be null. * @return An iterable for the given node list. */ public static Iterable<Node> nodeIterable(final NodeList nodeList) { return () -> DOMUtil.nodeIterator(nodeList); } /** * @param nodeList * Must not be null. * @return An iterator for the given node list. */ public static Iterator<Node> nodeIterator(final NodeList nodeList) { return new Iterator<Node>() { int index = 0; @Override public boolean hasNext() { return index < nodeList.getLength(); } @Override public Node next() { if (hasNext()) { return nodeList.item(index++); } else { throw new NoSuchElementException(); } } @Override public void remove() { throw new UnsupportedOperationException(); } }; } /** * @param nodeList * Must not be null. * @return An iterable for the given node list that ignores non-element nodes. */ public static Iterable<Element> elementIterable(final NodeList nodeList) { return () -> elementIterator(nodeList); } /** * @param nodeList * Must not be null. * @return An iterator for the given node list that ignores non-element nodes. */ public static Iterator<Element> elementIterator(final NodeList nodeList) { return new Iterator<Element>() { int i = 0; @Override public boolean hasNext() { while (i < nodeList.getLength() && !isElement(nodeList.item(i))) { i++; } return i < nodeList.getLength(); } @Override public Element next() { if (hasNext()) { return (Element) nodeList.item(i++); } else { throw new NoSuchElementException(); } } @Override public void remove() { throw new UnsupportedOperationException(); } }; } /** * Detaches an element from its parent. * * @param element * Must not be null. * @return True if calling this method detaches the given element from a parent node. False if there is no parent to * be removed from. */ public static boolean removeFromParent(final Element element) { if (element.getParentElement() != null) { element.getParentElement().removeChild(element); return true; } else { return false; } } /** * Detaches all children from a node. * * @param node * Must not be null. * @return True iff any children were detached by this call. */ public static boolean removeAllChildren(final Node node) { final boolean hadChildren = node.getLastChild() != null; while (node.getLastChild() != null) { node.removeChild(node.getLastChild()); } return hadChildren; } /** * Detaches all element children from a node. * * @param node * Must not be null. * @return True iff any element children were detached by this call. */ public static boolean removeAllElementChildren(final Node node) { boolean elementRemoved = false; for (final Element child : elementIterable(node.getChildNodes())) { node.removeChild(child); elementRemoved = true; } return elementRemoved; } /** * Removes a CSS class from an element's class list. * * @param element * Must not be null. * @param className * The name of a CSS class. Must not be null. * @return True if the given class was removed from the given element. False if the given element did not have the * given class as part of its class list. */ public static boolean removeCSSClass(final HTMLElement element, final String className) { if (hasCSSClass(element, className)) { element.getClassList().remove(className); return true; } else { return false; } } /** * Adds a CSS class to an element's class list. * * @param element * Must not be null. * @param className * The name of a CSS class. Must not be null. * @return True if the given class was added to the given element. False if the given element already had the * given class as part of its class list. */ public static boolean addCSSClass(final HTMLElement element, final String className) { if (hasCSSClass(element, className)) { return false; } else { element.getClassList().add(className); return true; } } /** * @param element * Must not be null. * @param className * The name of a CSS class. Must not be null. * @return True iff the given element has the given CSS class as part of its class list. */ public static boolean hasCSSClass(final HTMLElement element, final String className) { return element.getClassList().contains(className); } /** * @param tokenList * Must not be null. * @return A sequential, ordered {@link Stream} of tokens from the given {@link DOMTokenList}. */ public static Stream<String> tokenStream(final DOMTokenList tokenList) { return Stream.iterate(0, n -> n + 1).limit(tokenList.getLength()).map(i -> tokenList.item(i)); } /** * @param styleDeclaration * Must not be null. * @return A stream of property names from the given style declaration. */ public static Stream<String> cssPropertyNameStream(final CSSStyleDeclaration styleDeclaration) { return Arrays .stream(styleDeclaration.getCssText() != null ? styleDeclaration.getCssText().split(";") : new String[0]) .map(style -> style.split(":", 2)[0].trim()).filter(propertyName -> !propertyName.isEmpty()); } /** * Appends the underlying {@link HTMLElement} of a {@link Widget} to another {@link HTMLElement}, in a way that does * not break GWT Widget events. * * @param parent * The parent element that is appended to. Must not be null. * @param child * The child Widget, whose underlying HTML element will be appended to the parent. Must not be null. */ public static void appendWidgetToElement(final HTMLElement parent, final IsWidget child) { appendWidgetToElement(parent, child.asWidget()); } /** * Appends the underlying {@link HTMLElement} of a {@link Widget} to another {@link HTMLElement}, in a way that does * not break GWT Widget events. * * @param parent * The parent element that is appended to. Must not be null. * @param child * The child Widget, whose underlying HTML element will be appended to the parent. Must not be null. */ public static void appendWidgetToElement(final HTMLElement parent, final Widget child) { if (child.isAttached()) { child.removeFromParent(); } RootPanel.detachOnWindowClose(child); parent.appendChild(nativeCast(child.getElement())); onAttach(child); } /** * <p> * Remove a {@link Widget} from its parent. Use this to undo calls to * {@link #appendWidgetToElement(HTMLElement, IsWidget)}. * * <p> * This works like calling {@code child.asWidget().removeFromParent()} except that if {@code child} is in the * {@link RootPanel#isInDetachList(Widget) dettach list} its underlying HTML element will also be removed from its * parent. * * @param child * The child Widget, whose underlying HTML element will be removed from the parent. Must not be null. */ public static void removeFromParent(final IsWidget child) { removeFromParent(child.asWidget()); } /** * <p> * Remove a {@link Widget} from its parent. Use this to undo calls to * {@link #appendWidgetToElement(HTMLElement, Widget)}. * * <p> * This works like calling {@code child.removeFromParent()} except that if {@code child} is in the * {@link RootPanel#isInDetachList(Widget) dettach list} its underlying HTML element will also be removed from its * parent. * * @param child * The child Widget, whose underlying HTML element will be removed from the parent. Must not be null. */ public static void removeFromParent(final Widget child) { final boolean wasInDettachList = RootPanel.isInDetachList(child); child.removeFromParent(); if (wasInDettachList) { child.getElement().removeFromParent(); } } /** * Adds a unique enumerated CSS class to an element's class list removing all others * in the enumerated {@link Style.HasCssName}. Other CSS classes not in the enumerated * {@link Style.HasCssName} are preserved. * * @param element * Must not be null. * @param enumClass * The {@link Style.HasCssName} class. Must not be null. * @param style * The enumerated {@link Style.HasCssName} element. Must not be null. */ public static <E extends Style.HasCssName, F extends Enum<? extends Style.HasCssName>> void addUniqueEnumStyleName( final HTMLElement element, final Class<F> enumClass, final E style) { removeEnumStyleNames(element, enumClass); addEnumStyleName(element, style); } /** * Removes all of the enumerated CSS classes on an element's class list. * * @param element * Must not be null. * @param enumClass * The {@link Style.HasCssName} class. Must not be null. */ public static <E extends Enum<? extends Style.HasCssName>> void removeEnumStyleNames(final HTMLElement element, final Class<E> enumClass) { for (final Enum<? extends Style.HasCssName> constant : enumClass.getEnumConstants()) { final String cssClass = ((Style.HasCssName) constant).getCssName(); if (cssClass != null && !cssClass.isEmpty()) { removeCSSClass(element, cssClass); } } } /** * Adds an enumerated CSS class to an element's class list. * * @param element * Must not be null. * @param style * The enumerated {@link Style.HasCssName} element. Must not be null. */ public static <E extends Style.HasCssName> void addEnumStyleName(final HTMLElement element, final E style) { if (style != null && style.getCssName() != null && !style.getCssName().isEmpty()) { addCSSClass(element, style.getCssName()); } } /** * Removes the enumerated CSS class from an element's class list. * * @param element * Must not be null. * @param style * The enumerated {@link Style.HasCssName} element. Must not be null. */ public static <E extends Style.HasCssName> void removeEnumStyleName(final HTMLElement element, final E style) { if (style != null && style.getCssName() != null && !style.getCssName().isEmpty()) { removeCSSClass(element, style.getCssName()); } } private static native void onAttach(Widget w)/*-{ w.@com.google.gwt.user.client.ui.Widget::onAttach()(); }-*/; private static native HTMLElement nativeCast(com.google.gwt.dom.client.Element gwtElement)/*-{ return gwtElement; }-*/; }