SpannableStringGenerator.java

/***
 Copyright (c) 2015 CommonsWare, LLC

 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.commonsware.cwac.richtextutils;

import android.text.Spannable;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import java.io.IOException;
import java.io.StringReader;
import java.util.HashMap;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

/**
 * Class for converting XHTML generated by SpannedXhtmlGenerator
 * into a Spannable for use with TextView, EditText, etc.
 */

public class SpannableStringGenerator {
  static final private HashMap<String, SpanTagHandler> GLOBAL_SPAN_TAG_HANDLERS=
      new HashMap<String, SpanTagHandler>();
  private final SpanTagRoster roster;

  /**
   * Constructor, using a default SpanTagRoster.
   */
  public SpannableStringGenerator() {
    this(new SpanTagRoster());
  }

  /**
   * Constructor. 'nuff said.
   *
   * @param roster a SpanTagRoster of rules to apply
   */
  public SpannableStringGenerator(SpanTagRoster roster) {
    this.roster=roster;
  }

  /**
   * Generates a Spannable from supplied XHTML.
   *
   * @param src XHTML to be converted
   * @return the Spannable that is the results of the conversion
   * @throws ParserConfigurationException
   * @throws SAXException
   * @throws IOException
   */
  public Spannable fromXhtml(String src)
      throws ParserConfigurationException, SAXException, IOException {
    return(fromXhtml(SAXParserFactory.newInstance().newSAXParser(), src));
  }

  /**
   * Generates a Spannable from supplied XHTML.
   *
   * @param parser Parser for the source to use, in case you do not want to use a standard SAX parser
   * @param src XHTML to be converted
   * @return the Spannable that is the results of the conversion
   * @throws IOException
   * @throws SAXException
   */
  public Spannable fromXhtml(SAXParser parser, String src)
      throws IOException, SAXException {
    XhtmlSaxHandler saxHandler=new XhtmlSaxHandler(roster);

    StringBuilder xml=new StringBuilder("<SpannableStringGenerator>");

    xml.append(src);
    xml.append("</SpannableStringGenerator>");

    parser.parse(new InputSource(new StringReader(xml.toString())),
                  saxHandler);

    return(saxHandler.getContent());
  }
}