/* * 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.dom.client; import com.google.gwt.core.client.JavaScriptObject; import com.google.gwt.safehtml.shared.SafeHtml; /** * All HTML element interfaces derive from this class. */ public class Element extends Node { /** * Constant returned from {@link #getDraggable()}. */ public static final String DRAGGABLE_AUTO = "auto"; /** * Constant returned from {@link #getDraggable()}. */ public static final String DRAGGABLE_FALSE = "false"; /** * Constant returned from {@link #getDraggable()}. */ public static final String DRAGGABLE_TRUE = "true"; /** * Assert that the given {@link Node} is an {@link Element} and automatically * typecast it. */ public static Element as(JavaScriptObject o) { assert is(o); return (Element) o; } /** * Assert that the given {@link Node} is an {@link Element} and automatically * typecast it. */ public static Element as(Node node) { assert is(node); return (Element) node; } /** * Determines whether the given {@link JavaScriptObject} can be cast to an * {@link Element}. A <code>null</code> object will cause this method to * return <code>false</code>. */ public static boolean is(JavaScriptObject o) { if (Node.is(o)) { return is((Node) o); } return false; } /** * Determine whether the given {@link Node} can be cast to an {@link Element}. * A <code>null</code> node will cause this method to return * <code>false</code>. */ public static boolean is(Node node) { return (node != null) && (node.getNodeType() == Node.ELEMENT_NODE); } protected Element() { } /** * Adds a name to this element's class property. If the name is already * present, this method has no effect. * * @param className the class name to be added * @see #setClassName(String) */ public final void addClassName(String className) { assert (className != null) : "Unexpectedly null class name"; className = className.trim(); assert (className.length() != 0) : "Unexpectedly empty class name"; // Get the current style string. String oldClassName = getClassName(); int idx = oldClassName.indexOf(className); // Calculate matching index. while (idx != -1) { if (idx == 0 || oldClassName.charAt(idx - 1) == ' ') { int last = idx + className.length(); int lastPos = oldClassName.length(); if ((last == lastPos) || ((last < lastPos) && (oldClassName.charAt(last) == ' '))) { break; } } idx = oldClassName.indexOf(className, idx + 1); } // Only add the style if it's not already present. if (idx == -1) { if (oldClassName.length() > 0) { oldClassName += " "; } setClassName(oldClassName + className); } } /** * Removes keyboard focus from this element. */ public final native void blur() /*-{ this.blur(); }-*/; /** * Dispatched the given event with this element as its target. The event will * go through all phases of the browser's normal event dispatch mechanism. * * Note: Because the browser's normal dispatch mechanism is used, exceptions * thrown from within handlers triggered by this method cannot be caught by * wrapping this method in a try/catch block. Such exceptions will be caught * by the * {@link com.google.gwt.core.client.GWT#setUncaughtExceptionHandler(com.google.gwt.core.client.GWT.UncaughtExceptionHandler) uncaught exception handler} * as usual. * * @param evt the event to be dispatched */ public final void dispatchEvent(NativeEvent evt) { DOMImpl.impl.dispatchEvent(this, evt); } /** * Gives keyboard focus to this element. */ public final native void focus() /*-{ this.focus(); }-*/; /** * Gets an element's absolute bottom coordinate in the document's coordinate * system. */ public final int getAbsoluteBottom() { return getAbsoluteTop() + getOffsetHeight(); } /** * Gets an element's absolute left coordinate in the document's coordinate * system. */ public final int getAbsoluteLeft() { return DOMImpl.impl.getAbsoluteLeft(this); } /** * Gets an element's absolute right coordinate in the document's coordinate * system. */ public final int getAbsoluteRight() { return getAbsoluteLeft() + getOffsetWidth(); } /** * Gets an element's absolute top coordinate in the document's coordinate * system. */ public final int getAbsoluteTop() { return DOMImpl.impl.getAbsoluteTop(this); } /** * Retrieves an attribute value by name. Attribute support can be * inconsistent across various browsers. Consider using the accessors in * {@link Element} and its specific subclasses to retrieve attributes and * properties. * * @param name The name of the attribute to retrieve * @return The Attr value as a string, or the empty string if that attribute * does not have a specified or default value */ public final String getAttribute(String name) { return DOMImpl.impl.getAttribute(this, name); } /** * The class attribute of the element. This attribute has been renamed due to * conflicts with the "class" keyword exposed by many languages. * * @see <a * href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/global.html#adef-class">W3C * HTML Specification</a> */ public final native String getClassName() /*-{ return this.className; }-*/; /** * Returns the inner height of an element in pixels, including padding but not * the horizontal scrollbar height, border, or margin. * * @return the element's client height */ public final native int getClientHeight() /*-{ return this.clientHeight; }-*/; /** * Returns the inner width of an element in pixels, including padding but not * the vertical scrollbar width, border, or margin. * * @return the element's client width */ public final native int getClientWidth() /*-{ return this.clientWidth; }-*/; /** * Specifies the base direction of directionally neutral text and the * directionality of tables. */ public final native String getDir() /*-{ return this.dir; }-*/; /** * Returns the draggable attribute of this element. * * @return one of {@link #DRAGGABLE_AUTO}, {@link #DRAGGABLE_FALSE}, or * {@link #DRAGGABLE_TRUE} */ public final native String getDraggable() /*-{ return this.draggable || null; }-*/; /** * Returns a NodeList of all descendant Elements with a given tag name, in the * order in which they are encountered in a preorder traversal of this Element * tree. * * @param name The name of the tag to match on. The special value "*" matches * all tags * @return A list of matching Element nodes */ public final native NodeList<Element> getElementsByTagName(String name) /*-{ return this.getElementsByTagName(name); }-*/; /** * The first child of element this element. If there is no such element, this * returns null. */ public final Element getFirstChildElement() { return DOMImpl.impl.getFirstChildElement(this); } /** * The element's identifier. * * @see <a * href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/global.html#adef-id">W3C * HTML Specification</a> */ public final native String getId() /*-{ return this.id; }-*/; /** * All of the markup and content within a given element. */ public final String getInnerHTML() { return DOMImpl.impl.getInnerHTML(this); } /** * The text between the start and end tags of the object. */ public final String getInnerText() { return DOMImpl.impl.getInnerText(this); } /** * Language code defined in RFC 1766. */ public final native String getLang() /*-{ return this.lang; }-*/; /** * The element immediately following this element. If there is no such * element, this returns null. */ public final Element getNextSiblingElement() { return DOMImpl.impl.getNextSiblingElement(this); } /** * The height of an element relative to the layout. */ public final native int getOffsetHeight() /*-{ return this.offsetHeight || 0; }-*/; /** * The number of pixels that the upper left corner of the current element is * offset to the left within the offsetParent node. */ public final native int getOffsetLeft() /*-{ return this.offsetLeft || 0; }-*/; /** * Returns a reference to the object which is the closest (nearest in the * containment hierarchy) positioned containing element. */ public final native Element getOffsetParent() /*-{ return this.offsetParent; }-*/; /** * The number of pixels that the upper top corner of the current element is * offset to the top within the offsetParent node. */ public final native int getOffsetTop() /*-{ return this.offsetTop || 0; }-*/; /** * The width of an element relative to the layout. */ public final native int getOffsetWidth() /*-{ return this.offsetWidth || 0; }-*/; /** * The element immediately preceeding this element. If there is no such * element, this returns null. */ public final Element getPreviousSiblingElement() { return DOMImpl.impl.getPreviousSiblingElement(this); } /** * Gets a boolean property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native boolean getPropertyBoolean(String name) /*-{ return !!this[name]; }-*/; /** * Gets a double property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native double getPropertyDouble(String name) /*-{ return parseFloat(this[name]) || 0.0; }-*/; /** * Gets an integer property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native int getPropertyInt(String name) /*-{ return parseInt(this[name]) || 0; }-*/; /** * Gets a JSO property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native JavaScriptObject getPropertyJSO(String name) /*-{ return this[name] || null; }-*/; /** * Gets an object property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native Object getPropertyObject(String name) /*-{ return this[name] || null; }-*/; /** * Gets a property from this element. * * @param name the name of the property to be retrieved * @return the property value */ public final native String getPropertyString(String name) /*-{ return (this[name] == null) ? null : String(this[name]); }-*/; /** * The height of the scroll view of an element. */ public final native int getScrollHeight() /*-{ return this.scrollHeight || 0; }-*/; /** * The number of pixels that an element's content is scrolled from the left. * * <p> * If the element is in RTL mode, this method will return a negative value of * the number of pixels scrolled from the right. * </p> */ public final int getScrollLeft() { return DOMImpl.impl.getScrollLeft(this); } /** * The number of pixels that an element's content is scrolled from the top. */ public final native int getScrollTop() /*-{ return this.scrollTop || 0; }-*/; /** * The width of the scroll view of an element. */ public final native int getScrollWidth() /*-{ return this.scrollWidth || 0; }-*/; /** * Gets a string representation of this element (as outer HTML). * * We do not override {@link #toString()} because it is final in * {@link com.google.gwt.core.client.JavaScriptObject}. * * @return the string representation of this element */ public final String getString() { return DOMImpl.impl.toString(this); } /** * Gets this element's {@link Style} object. */ public final native Style getStyle() /*-{ return this.style; }-*/; /** * The index that represents the element's position in the tabbing order. * * @see <a href="http://www.w3.org/TR/1999/REC-html401-19991224/interact/forms.html#adef-tabindex">W3C HTML Specification</a> */ public final int getTabIndex() { return DOMImpl.impl.getTabIndex(this); } /** * Gets the element's full tag name, including the namespace-prefix if * present. * * @return the element's tag name */ public final String getTagName() { return DOMImpl.impl.getTagName(this); } /** * The element's advisory title. */ public final native String getTitle() /*-{ return this.title; }-*/; /** * Determines whether an element has an attribute with a given name. * * <p> * Note that IE, prior to version 8, will return false-positives for names * that collide with element properties (e.g., style, width, and so forth). * </p> * * @param name the name of the attribute * @return <code>true</code> if this element has the specified attribute */ public final boolean hasAttribute(String name) { return DOMImpl.impl.hasAttribute(this, name); } /** * Determines whether this element has the given tag name. * * @param tagName the tag name, including namespace-prefix (if present) * @return <code>true</code> if the element has the given tag name */ public final boolean hasTagName(String tagName) { assert tagName != null : "tagName must not be null"; return tagName.equals(getTagName()); } /** * Removes an attribute by name. */ public final native void removeAttribute(String name) /*-{ this.removeAttribute(name); }-*/; /** * Removes a name from this element's class property. If the name is not * present, this method has no effect. * * @param className the class name to be added * @see #setClassName(String) */ public final void removeClassName(String className) { assert (className != null) : "Unexpectedly null class name"; className = className.trim(); assert (className.length() != 0) : "Unexpectedly empty class name"; // Get the current style string. String oldStyle = getClassName(); int idx = oldStyle.indexOf(className); // Calculate matching index. while (idx != -1) { if (idx == 0 || oldStyle.charAt(idx - 1) == ' ') { int last = idx + className.length(); int lastPos = oldStyle.length(); if ((last == lastPos) || ((last < lastPos) && (oldStyle.charAt(last) == ' '))) { break; } } idx = oldStyle.indexOf(className, idx + 1); } // Don't try to remove the style if it's not there. if (idx != -1) { // Get the leading and trailing parts, without the removed name. String begin = oldStyle.substring(0, idx).trim(); String end = oldStyle.substring(idx + className.length()).trim(); // Some contortions to make sure we don't leave extra spaces. String newClassName; if (begin.length() == 0) { newClassName = end; } else if (end.length() == 0) { newClassName = begin; } else { newClassName = begin + " " + end; } setClassName(newClassName); } } /** * Replace one class name with another. * * @param oldClassName the class name to be replaced * @param newClassName the class name to replace it */ public final void replaceClassName(String oldClassName, String newClassName) { removeClassName(oldClassName); addClassName(newClassName); } /** * Scrolls this element into view. * * <p> * This method crawls up the DOM hierarchy, adjusting the scrollLeft and * scrollTop properties of each scrollable element to ensure that the * specified element is completely in view. It adjusts each scroll position by * the minimum amount necessary. * </p> */ public final void scrollIntoView() { DOMImpl.impl.scrollIntoView(this); } /** * Adds a new attribute. If an attribute with that name is already present in * the element, its value is changed to be that of the value parameter. * * @param name The name of the attribute to create or alter * @param value Value to set in string form */ public final native void setAttribute(String name, String value) /*-{ this.setAttribute(name, value); }-*/; /** * The class attribute of the element. This attribute has been renamed due to * conflicts with the "class" keyword exposed by many languages. * * @see <a * href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/global.html#adef-class">W3C * HTML Specification</a> */ public final native void setClassName(String className) /*-{ this.className = className; }-*/; /** * Specifies the base direction of directionally neutral text and the * directionality of tables. */ public final native void setDir(String dir) /*-{ this.dir = dir; }-*/; /** * Changes the draggable attribute to one of {@link #DRAGGABLE_AUTO}, * {@link #DRAGGABLE_FALSE}, or {@link #DRAGGABLE_TRUE}. * * @param draggable a String constants */ public final void setDraggable(String draggable) { DOMImpl.impl.setDraggable(this, draggable); } /** * The element's identifier. * * @see <a * href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/global.html#adef-id">W3C * HTML Specification</a> */ public final native void setId(String id) /*-{ this.id = id; }-*/; /** * All of the markup and content within a given element. */ public final native void setInnerHTML(String html) /*-{ this.innerHTML = html || ''; }-*/; /** * All of the markup and content within a given element. */ public final void setInnerSafeHtml(SafeHtml html) { setInnerHTML(html.asString()); } /** * The text between the start and end tags of the object. */ public final void setInnerText(String text) { DOMImpl.impl.setInnerText(this, text); } /** * Language code defined in RFC 1766. */ public final native void setLang(String lang) /*-{ this.lang = lang; }-*/; /** * Sets a boolean property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyBoolean(String name, boolean value) /*-{ this[name] = value; }-*/; /** * Sets a double property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyDouble(String name, double value) /*-{ this[name] = value; }-*/; /** * Sets an integer property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyInt(String name, int value) /*-{ this[name] = value; }-*/; /** * Sets a JSO property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyJSO(String name, JavaScriptObject value) /*-{ this[name] = value; }-*/; /** * Sets an object property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyObject(String name, Object value) /*-{ this[name] = value; }-*/; /** * Sets a property on this element. * * @param name the name of the property to be set * @param value the new property value */ public final native void setPropertyString(String name, String value) /*-{ this[name] = value; }-*/; /** * The number of pixels that an element's content is scrolled to the left. */ public final void setScrollLeft(int scrollLeft) { DOMImpl.impl.setScrollLeft(this, scrollLeft); } /** * The number of pixels that an element's content is scrolled to the top. */ public final native void setScrollTop(int scrollTop) /*-{ this.scrollTop = scrollTop; }-*/; /** * The index that represents the element's position in the tabbing order. * * @see <a href="http://www.w3.org/TR/1999/REC-html401-19991224/interact/forms.html#adef-tabindex">W3C HTML Specification</a> */ public final native void setTabIndex(int tabIndex) /*-{ this.tabIndex = tabIndex; }-*/; /** * The element's advisory title. */ public final native void setTitle(String title) /*-{ // Setting the title to null results in the string "null" being displayed // on some browsers. this.title = title || ''; }-*/; }