Android中创建与几种解析xml的方法.doc

大家好今天我今天给大家讲解一下android中xml的创建以及一些解析xml的常用方法。首先是创建，我们用XmlSerializer这个类来创建一个xml文件，其次是解析xml文件，常用的有dom,sax,XmlPullParser等方法，由于sax代码有点复杂，本节只讲解一下dom与XmlPullParser解析，sax我将会在下一节单独讲解,至于几种解析xml的优缺点我就不再讲述了。为了方便理解，我做了一个简单的Demo。首先首界面有三个按钮，点击第一个按钮会在sdcard目录下创建一个books.xml文件,另外两个按钮分别是调用dom与XmlPullParser方法解析xml文件，并将结果显示在一个TextView里。大家可以按照我的步骤一步步来:第一步:新建一个Android工程,命名为XmlDemo.第二步:修改main.xml布局文件，代码如下:view plaincopy to clipboardprint?1. 2. 7. 13. 19. 25. 30. Error! Reference source not found.第三步:修改主核心程序XmlDemo.java,代码如下:view plaincopy to clipboardprint?1. package com.tutor.xml; 2. import java.io.File; 3. import java.io.FileNotFoundException; 4. import java.io.FileOutputStream; 5. import java.io.IOException; 6. import javax.xml.parsers.DocumentBuilder; 7. import javax.xml.parsers.DocumentBuilderFactory; 8. import javax.xml.parsers.ParserConfigurationException; 9. import org.w3c.dom.Document; 10. import org.w3c.dom.Element; 11. import org.w3c.dom.NodeList; 12. import org.xml.sax.SAXException; 13. import org.xmlpull.v1.XmlPullParser; 14. import org.xmlpull.v1.XmlPullParserException; 15. import org.xmlpull.v1.XmlPullParserFactory; 16. import org.xmlpull.v1.XmlSerializer; 17. import android.app.Activity; 18. import android.os.Bundle; 19. import android.util.Log; 20. import android.util.Xml; 21. import android.view.View; 22. import android.view.View.OnClickListener; 23. import android.widget.Button; 24. import android.widget.TextView; 25. import android.widget.Toast; 26. public class XmlDemo extends Activity implements OnClickListener 27.28. private static final String BOOKS_PATH = /sdcard/books.xml; 29. private Button mButton1,mButton2,mButton3; 30. private TextView mTextView; 31. Override 32. public void onCreate(Bundle savedInstanceState) 33. super.onCreate(savedInstanceState); 34. setContentView(R.layout.main); 35. setupViews(); 36. 37. /初始化工作 38. private void setupViews() 39. mTextView = (TextView)findViewById(R.id.result); 40. mButton1 = (Button)findViewById(R.id.btn1); 41. mButton2 = (Button)findViewById(R.id.btn2); 42. mButton3 = (Button)findViewById(R.id.btn3); 43. mButton1.setOnClickListener(this); 44. mButton2.setOnClickListener(this); 45. mButton3.setOnClickListener(this); 46. 47. /创建xml文件 48. private void createXmlFile() 49. File linceseFile = new File(BOOKS_PATH); 50. try 51. linceseFile.createNewFile(); 52. catch (IOException e) 53. Log.e(IOException, exception in createNewFile() method); 54. 55. FileOutputStream fileos = null; 56. try 57. fileos = new FileOutputStream(linceseFile); 58. catch (FileNotFoundException e) 59. Log.e(FileNotFoundException, cant create FileOutputStream); 60. 61. XmlSerializer serializer = Xml.newSerializer(); 62. try 63. serializer.setOutput(fileos,UTF-8); 64. serializer.startDocument(null, true); 65. serializer.startTag(null, books); 66. for(int i = 0; i 3; i +) 67. serializer.startTag(null, book); 68. serializer.startTag(null, bookname); 69. serializer.text(Android教程 + i); 70. serializer.endTag(null, bookname); 71. serializer.startTag(null, bookauthor); 72. serializer.text(Frankie + i); 73. serializer.endTag(null, bookauthor); 74. serializer.endTag(null, book); 75. 76.77. serializer.endTag(null, books); 78. serializer.endDocument(); 79. serializer.flush(); 80. fileos.close(); 81. catch (Exception e) 82. Log.e(Exception,error occurred while creating xml file); 83. 84. Toast.makeText(getApplicationContext(), 创建xml文件成功!, Toast.LENGTH_SHORT).show(); 85. 86. /dom解析xml文件 87. private void domParseXML() 88. File file = new File(BOOKS_PATH); 89. DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); 90. DocumentBuilder db = null; 91. try 92. db = dbf.newDocumentBuilder(); 93. catch (ParserConfigurationException e) 94. e.printStackTrace(); 95. 96. Document doc = null; 97. try 98. doc = db.parse(file); 99. catch (SAXException e) 100. e.printStackTrace(); 101. catch (IOException e) 102. e.printStackTrace(); 103. 104. Element root = doc.getDocumentElement(); 105. NodeList books = root.getElementsByTagName(book); 106. String res = 本结果是通过dom解析: + /n; 107. for(int i = 0; i books.getLength();i+) 108. Element book = (Element)books.item(i); 109. Element bookname = (Element)book.getElementsByTagName(bookname).item(0); 110. Element bookauthor = (Element)book.getElementsByTagName(bookauthor).item(0); 111. res += 书名: + bookname.getFirstChild().getNodeValue() + + 112. 作者: + bookauthor.getFirstChild().getNodeValue() + /n; 113. 114.115. mTextView.setText(res); 116. 117.118. /xmlPullParser解析xml文件 119. private void xmlPullParseXML() 120. String res = 本结果是通过XmlPullParse解析: + /n; 121. try 122. XmlPullParserFactory factory = XmlPullParserFactory.newInstance(); 123. XmlPullParser xmlPullParser = factory.newPullParser(); 124.125. xmlPullParser.setInput(Thread.currentThread().getContextClassLoader() 126. .getResourceAsStream(BOOKS_PATH), UTF-8); 127.128. int eventType = xmlPullParser.getEventType(); 129.130. try 131. while (eventType != XmlPullParser.END_DOCUMENT) 132. String nodeName = xmlPullParser.getName(); 133. switch (eventType) 134. case XmlPullParser.START_TAG: 135. if(bookname.equals(nodeName) 136. res += 书名: + xmlPullParser.nextText() + ; 137. else if(bookauthor.equals(nodeName) 138. res += 作者: + xmlPullParser.nextText() + /n; 139. 140. break; 141. default: 142. break; 143. 144. eventType = xmlPullParser.next(); 145. 146. catch (IOException e) 147. e.printStackTrace(); 148. 149. catch (XmlPullParserException e) 150. e.printStackTrace(); 151. 152.153. mTextView.setText(res); 154. 155. /按钮事件响应 156. public void onClick(View v) 157. if(v = m