java - 为什么无法解析此 XML 文件？

Question

我正在制作英语听力申请

我需要显示级别、名称、音频文件的名称、测试的脚本。我想从 XML 文件中读取信息:"dataeasy.xml"

但我什至可以读取 dataeasy.xml 的第一个元素

这是我所做的:

• activity_main.xml

  <?xml version="1.0" encoding="utf-8"?>
  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/linearlayoutXML1"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="#66CCFF"
  android:orientation="vertical" >
  
  
  <TextView
  android:id="@+id/textViewLessonLevel"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:textSize="30sp"
  android:textColor="#000000"
  android:textStyle="bold"
  android:text="Lesson Level"
  android:layout_gravity="center_horizontal"/>
  
  
  <TextView
  android:id="@+id/textViewLessonName"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:textSize="15sp"
  android:textColor="#7f7f7f"
  android:textStyle="bold"
  android:text="Lesson Name"
  android:layout_gravity="center_horizontal" />
  
  <TextView
  android:id="@+id/textViewLessonLinkFile"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:textSize="20sp"
  android:textColor="#865521"
  android:textStyle="bold"
  android:text="Lesson LinkFile"
  android:layout_gravity="center_horizontal"
  android:layout_marginLeft="40dp"
  android:layout_marginRight="40dp" />
  
  <TextView
  android:id="@+id/textViewLessonScript"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:textSize="20sp"
  android:textColor="#865521"
  android:textStyle="bold"
  android:text="Lesson Scipt"
  android:layout_gravity="center_horizontal"
  android:layout_marginLeft="40dp"
  android:layout_marginRight="40dp" />
  
  
  
  </LinearLayout>
  

• DataEasyXML.java

   public class DataEasyXML extends DefaultHandler {
  
   boolean currentElement = false;
   String currentValue = "";
  
   // Array of lessons
   LessonEasyInfo lessonEasyInfo;
   ArrayList<LessonEasyInfo> List;
  
  
   public ArrayList<LessonEasyInfo> getList() {
       return List;
   }
  
   public void startElement(String uri, String localName, String qName,
                       Attributes attributes) throws SAXException {
  
       currentElement = true;
  
       if (qName.equals("Data")) {
           List = new ArrayList<LessonEasyInfo>();
       } else if (qName.equals("Lesson")) {
           lessonEasyInfo = new LessonEasyInfo();
       }
   }
  
   public void endElement(String uri, String localName, String qName)
           throws SAXException {
  
       currentElement = false;
  
       if (qName.equalsIgnoreCase("Level"))
           lessonEasyInfo.setLevel(currentValue.trim());
       else if (qName.equalsIgnoreCase("Name"))
           lessonEasyInfo.setName(currentValue.trim());
       else if (qName.equalsIgnoreCase("LinkFile"))
           lessonEasyInfo.setLinkFile(currentValue.trim());
       else if (qName.equalsIgnoreCase("Script"))
           lessonEasyInfo.setScript(currentValue.trim());
       else if (qName.equalsIgnoreCase("Level"))
           List.add(lessonEasyInfo);
  
       currentValue = "";
   }
  
   public void characters(char[] ch, int start, int length)
           throws SAXException {
  
       if (currentElement) {
           currentValue = currentValue + new String(ch, start, length);
       }
   }
   }
  

• LessonEasyInfo.java

   public class LessonEasyInfo {
  
   String level = null;
   String name = "";
   String link = "";
   String script = "";
  
   public String getLevel() {
       return level;
   }
  
   public void setLevel(String level) {
       this.level = level;
   }
  
   public String getName() {
       return name;
   }
  
   public void setName(String name) {
       this.name = name;
   }
  
   public String getLinkFile() {
       return link;
   }
  
   public void setLinkFile(String link) {
      this.link = link;
   }
  
   public String getScript() {
       return script;
   }
  
   public void setScript(String script) {
       this.script = script;
   }
  

• MainActivity.java

   public class MainActivity extends Activity {
  
   TextView tvLessonLevel;
   TextView tvLessonName;
   TextView tvLessonLinkFile;
   TextView tvLessonScript;
  
   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
  
       tvLessonLevel = (TextView)findViewById(R.id.textViewLessonLevel);
       tvLessonName = (TextView)findViewById(R.id.textViewLessonName);
       tvLessonLinkFile = (TextView)findViewById(R.id.textViewLessonLinkFile);
       tvLessonScript = (TextView)findViewById(R.id.textViewLessonScript);
  
  
  
       parsedataeasyXML();
   }
  
   private void parsedataeasyXML(){
       // 
       AssetManager assetManager = getBaseContext().getAssets();
       try {
           //Get "dataeasy.xml"
           InputStream is = assetManager.open("dataeasy.xml");
           //
           SAXParserFactory spf = SAXParserFactory.newInstance();
           SAXParser sp = spf.newSAXParser();
           //Read XML Object
           XMLReader xr = sp.getXMLReader();
  
           // My
           DataEasyXML myXMLHandler = new DataEasyXML();
           //
           xr.setContentHandler(myXMLHandler);
           //Input
           InputSource inStream = new InputSource(is);
  
           xr.parse(inStream);
  
           // get the first element
           ArrayList<LessonEasyInfo> List = myXMLHandler.getList();
  
          tvLessonLevel.setText("Level: " + List.get(0).getLevel());
  
  
               tvLessonName.setText("Name: " + List.get(0).getName());
  
  
               tvLessonLinkFile.setText("LinkFile : " + List.get(0).getLinkFile());
  
               tvLessonScript.setText("Script " + List.get(0).getScript());
  
  
  
           is.close();
       } catch (Exception e) {
           e.printStackTrace();
       }
   }
  

  }

• dataeasy.xml(数据库文件):我在这里只写了 2 个元素

  链接在这里:here

Answer 1

以下代码块永远不会将任何 LessonEasyInfo 对象添加到列表中，因为如果第一个 if 表达式的计算结果为 true，则其他均未进行评估。

 if (qName.equalsIgnoreCase("Level"))
     lessonEasyInfo.setLevel(currentValue.trim());
 else if (qName.equalsIgnoreCase("Name"))
     lessonEasyInfo.setName(currentValue.trim());
 else if (qName.equalsIgnoreCase("LinkFile"))
     lessonEasyInfo.setLinkFile(currentValue.trim());
 else if (qName.equalsIgnoreCase("Script"))
     lessonEasyInfo.setScript(currentValue.trim());
 else if (qName.equalsIgnoreCase("Level"))
     List.add(lessonEasyInfo);

将上面的代码改成这样

 if (qName.equalsIgnoreCase("Level")) {
     lessonEasyInfo.setLevel(currentValue.trim());
     List.add(lessonEasyInfo);
 }
 else if (qName.equalsIgnoreCase("Name"))
     lessonEasyInfo.setName(currentValue.trim());
 else if (qName.equalsIgnoreCase("LinkFile"))
     lessonEasyInfo.setLinkFile(currentValue.trim());
 else if (qName.equalsIgnoreCase("Script"))
     lessonEasyInfo.setScript(currentValue.trim());