/*
* 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.uibinder.parsers;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.uibinder.rebind.UiBinderWriter;
import com.google.gwt.uibinder.rebind.XMLElement;
import com.google.gwt.uibinder.rebind.messages.MessageWriter;
import com.google.gwt.uibinder.rebind.messages.MessagesWriter;
import com.google.gwt.uibinder.rebind.messages.PlaceholderInterpreter;
/**
* Interprets the interior of an html message. Extends the basic
* PlaceholderInterpreter to handle dom elements with field names and computed
* attributes--basically any dom attribute that cannot live in a static value
* and so must be wrapped in a placeholder. (Note that the interior of such an
* element is processed with a recursive call to
* {@link XMLElement#consumeInnerHtml}.)
*/
class HtmlPlaceholderInterpreter extends PlaceholderInterpreter {
private int serial = 0;
private final XMLElement.Interpreter<String> fieldAndComputed;
HtmlPlaceholderInterpreter(UiBinderWriter writer,
MessageWriter message, String ancestorExpression) {
super(writer, message);
fieldAndComputed =
InterpreterPipe.newPipe(new FieldInterpreter(writer,
ancestorExpression), new ComputedAttributeInterpreter(writer));
}
@Override
public String interpretElement(XMLElement elem)
throws UnableToCompleteException {
fieldAndComputed.interpretElement(elem);
if (isDomPlaceholder(elem)) {
MessagesWriter mw = uiWriter.getMessages();
String name = mw.consumeMessageAttribute("ph", elem);
if ("".equals(name)) {
name = "htmlElement" + (++serial);
}
String openTag = elem.consumeOpeningTag();
String openPlaceholder =
nextPlaceholder(name + "Begin", stripTokens(openTag),
uiWriter.detokenate(openTag));
/*
* This recursive innerHtml call has already been escaped. Hide it in a
* token to avoid double escaping
*/
String body = tokenator.nextToken(elem.consumeInnerHtml(this));
String closeTag = elem.getClosingTag();
String closePlaceholder =
nextPlaceholder(name + "End", closeTag, closeTag);
return openPlaceholder + body + closePlaceholder;
}
return super.interpretElement(elem);
}
@Override
protected String consumePlaceholderInnards(XMLElement elem)
throws UnableToCompleteException {
return elem.consumeInnerHtml(fieldAndComputed);
}
/**
* An element will require a placeholder if the user has called it out with a
* ui:ph attribute, or if it will require run time swizzling (e.g. has a
* ui:field). These latter we can identify easily because they'll have an
* attribute that holds a tokenator token that was vended by
* {@link UiBinderWriter}, typically in id.
*
* @return true if it has an ui:ph attribute, or has a token in any attribute
*/
private boolean isDomPlaceholder(XMLElement elem) {
MessagesWriter mw = uiWriter.getMessages();
if (mw.hasMessageAttribute("ph", elem)) {
return true;
}
for (int i = elem.getAttributeCount() - 1; i >= 0; i--) {
if (elem.getAttribute(i).hasToken()) {
return true;
}
}
return false;
}
}