/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.waveprotocol.wave.client.editor.content.paragraph;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.Node;
import org.waveprotocol.wave.client.common.util.UserAgent;
import org.waveprotocol.wave.client.editor.EditorStaticDeps;
import org.waveprotocol.wave.client.editor.content.ContentElement;
import org.waveprotocol.wave.client.editor.content.ContentNode;
import org.waveprotocol.wave.common.logging.LoggerBundle;
/**
* Helps {@link Paragraph}. Deferred binding adds per-browser code.
*
* Browsers do not render empty <p> elements with enough space
* for a caret, nor with margins/padding, etc. Therefore, we need
* to add various type of 'spacers' that works with the browsers
* native editors.
*
* Unfortunately, the browsers have rather different idiosyncrasies
* in this area, thus the deferred binding for this class.
*
*/
public class ParagraphHelper {
/**
* Deferred binding helper.
*/
public static final ParagraphHelper INSTANCE = UserAgent.isIE() ? new ParagraphHelperIE()
: (UserAgent.isWebkit() ? new ParagraphHelperWebkit() : new ParagraphHelperAlwaysBr());
/**
* Borrow editor's logger
*/
public static LoggerBundle logger = EditorStaticDeps.logger;
public static ParagraphHelper create() {
return UserAgent.isIE() ? new ParagraphHelperIE() : (UserAgent.isWebkit()
? new ParagraphHelperWebkit() : new ParagraphHelperAlwaysBr());
}
public Node getEndingNodelet(Element paragraph) {
return null;
}
/**
* Handles the paragraph being emptied
*
* @param paragraph
*/
public void onEmpty(Element paragraph) {}
/**
* Handles a child being added to the paragraph
*
* @param child
* @param paragraph
*/
public void onChildAdded(Node child, Element paragraph) {}
/**
* Handles a child being removed to the paragraph
*
* @param child
* @param paragraph
*/
public void onRemovingChild(Node child, Element paragraph) {}
/**
* Handles the paragraph repairing itself
* @param paragraph
*/
public void onRepair(ContentElement paragraph) {}
/**
* See @link {@link ContentNode#debugAssertHealthy()}
* @param paragraph
*/
public void assertHealthy(ContentElement paragraph) {}
}