Question

i try to build an application with xml parser.

ex : http://www.androidpeople.com/android-xml-parsing-tutorial-using-saxparser

but i want to parse xml file from EditText, how it work ?

Answer 1

You have several ways to parse XML, the most widely used being SAX and DOM. The choice is quite strategical as explained in this paper.

Here is a short explanation of SAX:

• You will need some imports:

  import org.xml.sax.Attributes;
  import org.xml.sax.SAXException;
  import org.xml.sax.SAXParseException;
  import org.xml.sax.helpers.DefaultHandler;
  import android.util.Xml;
  

• Create your own XML SAX DefaultHandler:

  class MySaxHandler extends DefaultHandler {
      // Override the methods of DefaultHandler that you need.
      // See [this link][3] to see these methods.
      // These methods are going to be called while the XML is read
      // and will allow you doing what you need with the content.
      // Two examples below:
  
      public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
           // This is called each time an openeing XML tag is read.
           // As the tagname is passed by parameter you know which tag it is.
           // You also have the attributes of the tag.
           // Example <mytag myelem="12"> will lead to a call of
           // this method with the parameters:
           // - localName = "mytag"
           // - attributes = { "myelem", "12" }  
      }
  
      public void characters(char[] ch, int start, int length) throws SAXException {
           // This is called each time some text is read.
           // As an example, if you have <myTag>blabla</myTag>
           // this will be called with the parameter "blabla"
           // Warning 1: this is also called when linebreaks are read and the linebreaks are passed
           // Warning 2: you have to memorize the last open tag to determine what tag this text belongs to (I usually use a stack).
      }
  }
  

• Extract the XML as a String from the EditText. Let’s call it xmlContent

• Create and initialize your XML parser:

  final InputStreamReader reader = new InputStreamReader(new ByteArrayInputStream(xmlContent.getBytes()));
  final MySaxHandler handler = new MySaxHandler();
  

• And then, make the XML content to be read by the parser. This will lead your MySaxHandler to have its various method called while the reading is in progress.

  Xml.parse(reader, handler);