/*
* Copyright 2006 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.user.client.ui;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.i18n.shared.DirectionEstimator;
import com.google.gwt.safehtml.shared.SafeHtml;
/**
* A widget that can contain arbitrary HTML.
*
* This widget uses a <div> element, causing it to be displayed with block
* layout.
*
* <p>
* If you only need a simple label (text, but not HTML), then the
* {@link com.google.gwt.user.client.ui.Label} widget is more appropriate, as it
* disallows the use of HTML, which can lead to potential security issues if not
* used properly.
* </p>
*
* <p>
* <h3>Built-in Bidi Text Support</h3>
* This widget is capable of automatically adjusting its direction according to
* its content. This feature is controlled by {@link #setDirectionEstimator} or
* passing a DirectionEstimator parameter to the constructor, and is off by
* default.
* </p>
*
* <h3>CSS Style Rules</h3>
* <ul class='css'>
* <li>.gwt-HTML { }</li>
* </ul>
*
* <p>
* <h3>Example</h3>
* {@example com.google.gwt.examples.HTMLExample}
* </p>
*/
public class HTML extends Label
implements HasDirectionalHtml, HasDirectionalSafeHtml {
/**
* Creates an HTML widget that wraps an existing <div> or <span>
* element.
*
* This element must already be attached to the document. If the element is
* removed from the document, you must call
* {@link RootPanel#detachNow(Widget)}.
*
* @param element the element to be wrapped
*/
public static HTML wrap(Element element) {
// Assert that the element is attached.
assert Document.get().getBody().isOrHasChild(element);
HTML html = new HTML(element);
// Mark it attached and remember it for cleanup.
html.onAttach();
RootPanel.detachOnWindowClose(html);
return html;
}
/**
* Creates an empty HTML widget.
*/
public HTML() {
super(Document.get().createDivElement());
setStyleName("gwt-HTML");
}
/**
* Initializes the widget's HTML from a given {@link SafeHtml} object.
*
* @param html the new widget's HTML contents
*/
public HTML(SafeHtml html) {
this(html.asString());
}
/**
* Creates an HTML widget with the specified contents and with the specified
* direction.
*
* @param html the new widget's SafeHtml contents
* @param dir the content's direction. Note: {@code Direction.DEFAULT} means
* direction should be inherited from the widget's parent element.
*/
public HTML(SafeHtml html, Direction dir) {
this(html.asString(), dir);
}
/**
* Creates an HTML widget with the specified HTML contents and specifies a
* direction estimator.
*
* @param html the new widget's SafeHtml contents
* @param directionEstimator A DirectionEstimator object used for automatic
* direction adjustment. For convenience,
* {@link Label#DEFAULT_DIRECTION_ESTIMATOR} can be used.
*/
public HTML(SafeHtml html, DirectionEstimator directionEstimator) {
this();
setDirectionEstimator(directionEstimator);
setHTML(html);
}
/**
* Creates an HTML widget with the specified HTML contents.
*
* @param html the new widget's HTML contents
*/
public HTML(String html) {
this();
setHTML(html);
}
/**
* Creates an HTML widget with the specified HTML contents and with the
* specified direction.
*
* @param html the new widget's HTML contents
* @param dir the content's direction. Note: {@code Direction.DEFAULT} means
* direction should be inherited from the widget's parent element.
*/
public HTML(String html, Direction dir) {
this();
setHTML(html, dir);
}
/**
* Creates an HTML widget with the specified contents, optionally treating it
* as HTML, and optionally disabling word wrapping.
*
* @param html the widget's contents
* @param wordWrap <code>false</code> to disable word wrapping
*/
public HTML(String html, boolean wordWrap) {
this(html);
setWordWrap(wordWrap);
}
/**
* This constructor may be used by subclasses to explicitly use an existing
* element. This element must be either a <div> or <span> element.
*
* @param element the element to be used
*/
protected HTML(Element element) {
// super(element) asserts that element is either a <div> or
// <span>.
super(element);
}
public String getHTML() {
return directionalTextHelper.getTextOrHtml(true);
}
/**
* Sets the label's content to the given HTML.
* See {@link #setText(String)} for details on potential effects on direction
* and alignment.
*
* @param html the new widget's HTML content
*/
public void setHTML(String html) {
directionalTextHelper.setTextOrHtml(html, true);
updateHorizontalAlignment();
}
/**
* Sets the label's content to the given HTML, applying the given direction.
* See
* {@link #setText(String, com.google.gwt.i18n.client.HasDirection.Direction) setText(String, Direction)}
* for details on potential effects on alignment.
*
* @param html the new widget's HTML content
* @param dir the content's direction. Note: {@code Direction.DEFAULT} means
* direction should be inherited from the widget's parent element.
*/
public void setHTML(String html, Direction dir) {
directionalTextHelper.setTextOrHtml(html, dir, true);
updateHorizontalAlignment();
}
/**
* Sets this object's contents via known-safe HTML.
*
* @see com.google.gwt.safehtml.client.HasSafeHtml#setHTML(SafeHtml)
* @param html the html to set.
*/
public void setHTML(SafeHtml html) {
setHTML(html.asString());
}
public void setHTML(SafeHtml html, Direction dir) {
setHTML(html.asString(), dir);
}
protected String getTextOrHtml(boolean isHtml) {
return directionalTextHelper.getTextOrHtml(isHtml);
}
}