您好我正在使用Android应用程序，它将解析值并显示列表视图。我正在使用XML解析方法来解析数据并成功显示在listview中。现在问题是当我尝试解析没有值（NULL）的xml标记时，它会产生错误并强制关闭应用程序。我尝试，如果节点具有某些值，那么只允许解析仍然显示一些问题，并且只有第一个标签显示在第一个列表项中。其他列表项目什么都没有显示。
Below is the xml tags to parse.
<UserScore>
<GameId>daily_1349375400</GameId>
<Location></Location>
<GameName>Football - 5th October 2013</GameName>
<Date>Oct 5, 2013</Date>
</UserScore>
−
<UserScore>
<GameId>136</GameId>
<GameName>Company Cricket</GameName>
<Location>France </Location>
<Date>Jan 6, 2012</Date>
</UserScore>
For the first time the location tag having "france" as its value, but when again played the second location tag contains nothing.
Here is my coding please tell me the solution.
public class AsynTaskScoreboard extends AsyncTask<Void, Void, Void> {
private ProgressDialog dialog = ProgressDialog.show(getParent(), "Retrieving data ", " Loading. Please wait ... ", true);
// can use UI thread here
protected void onPreExecute() {
this.dialog.setMessage("Loading...");
this.dialog.setCancelable(false);
this.dialog.show();
}
@Override
protected Void doInBackground(Void... params) {
try {
URL xpto = new URL(my url here);
HttpURLConnection conn;
conn = (HttpURLConnection) xpto.openConnection();
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(is);
doc.getDocumentElement().normalize();
NodeList nodeList;
nodeList = doc.getElementsByTagName("TotalPoints");
Log.d("Background", "TotalPoints " + nodeList);
for (int i = 0; i < nodeList.getLength(); i++) {
Node name = nodeList.item(i);
NodeList nodeEle = name.getChildNodes();
strTotalPoints = ((Node) nodeEle.item(0)).getNodeValue();
Log.d("Background", "TotalPoints " + nodeList);
}
nodeList = doc.getElementsByTagName("ChallengesPlayed");
for (int i = 0; i < nodeList.getLength(); i++) {
Node name = nodeList.item(i);
NodeList nodeEle = name.getChildNodes();
strChallengesPoint = ((Node) nodeEle.item(0)).getNodeValue();
}
android.os.Message msg = Message.obtain();
msg.what = 11;
handler.sendMessage(msg);
/**
* Check whether it is my points or high score
*/
switch (flagMypointsOrHighScore) {
case 0:
nodeList = doc.getElementsByTagName("UserScore");
// Define Array based on nodelist
arrLength = nodeList.getLength();
strGameid = new String[arrLength];
strGameNameArr = new String[arrLength];
strGameLocationArr = new String[arrLength];
strGameDate = new String[arrLength];
String[] strXMLTag = { "GameId", "GameName", "Location", "Date" };
for (int i = 0; i < arrLength; i++) {
Node node = nodeList.item(i);
Log.d("scoreList", "node " + node);
Element fstElmnt = (Element) node;
Log.d("scoreList", "fstElmnt " + fstElmnt);
for (int j = 0; j < strXMLTag.length; j++) {
NodeList scoreList = fstElmnt.getElementsByTagName(strXMLTag[j]);
Element scoreElement = (Element) scoreList.item(0);
scoreList = scoreElement.getChildNodes();
switch (j) {
case 0:
strGameid[i] = ((Node) scoreList.item(0)).getNodeValue();
break;
case 1:
strGameNameArr[i] = ((Node) scoreList.item(0)).getNodeValue();
break;
case 2:
strGameLocationArr[i]=((Node) scoreList.item(0)).getNodeValue();
break;
case 3:
strGameDate[i] = ((Node) scoreList.item(0)).getNodeValue();
break;
}
}
}// End of for loop
// Your rank
break;
case 1:// Top rank 5
nodeList = doc.getElementsByTagName("Top5Rank");
// Define Array based on nodelist
arrLength = nodeList.getLength();
strGameNameArr = new String[arrLength];
strGameLocationArr = new String[arrLength];
strGameDate = new String[arrLength];
for (int i = 0; i < arrLength; i++) {
Node node = nodeList.item(i);
Element fstElmnt = (Element) node;
NodeList rankList = fstElmnt.getElementsByTagName("Person");
//
int rankListLength = rankList.getLength();
if (strPersonNameArr == null) {
strPersonNameArr = new String[rankListLength];
strPersonRankArr = new String[rankListLength];
strPersoonPointsArr = new String[rankListLength];
}
for (int j = 0; j < rankListLength; j++) {
rankList = fstElmnt.getElementsByTagName("Person");
Element rankElement = (Element) rankList.item(j);
rankList = rankElement.getChildNodes();
strPersonNameArr[j] = rankElement.getAttribute("Name");
strPersonRankArr[j] = rankElement.getAttribute("Rank");
strPersoonPointsArr[j] = rankElement.getAttribute("Points");
}
}// End of for loop
break;
}// End of switch
} catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}// try below db 2try
} catch (Exception e) {
// TODO Auto-generated catch block
if (e.toString().equalsIgnoreCase("java.net.SocketException: Network unreachable")) {
android.os.Message msg = android.os.Message.obtain();
msg.what = 0;
handler.sendMessage(msg);
}
e.printStackTrace();
}
return null;
}// End of do in background method
// do the stuff after the heavy task
protected void onPostExecute(Void result) {
android.os.Message msg = Message.obtain();
switch (flagMypointsOrHighScore) {
case 0:
listViewMyPoints.setAdapter(new JR_LB_ListAdapter(ScoreboardActivity.this));
break;
case 1:
listViewHighScores.setAdapter(new JR_LB_ListAdapter_HighScores(ScoreboardActivity.this));
// Set textview value in the
msg.what = 10;
handler.sendMessage(msg);
break;
default:
}
if (this.dialog.isShowing()) {
this.dialog.dismiss();
}
}// End of on post execute method
@Override
protected void onProgressUpdate(Void... values) {
// TODO Auto-generated method stub
Totalpoint.setText(strTotalPoints);
challengeplay.setText(strChallengesPoint);
txtViewRank.setText(strRank);
txtViewPoint.setText(strPoint);
txtViewPersonName.setText(strPersonName);
Log.d("ProgressUpdate", "strTotalPoints " + strTotalPoints);
Log.d("ProgressUpdate", "strChallengesPoint " + strChallengesPoint);
Log.d("ProgressUpdate", "strRank " + strRank);
Log.d("ProgressUpdate", "strPoint " + strPoint);
}
}// End of Asynchronous task class
在asynctask之后，我通过意图将值传递给下一个活动。在那个值也传递为null。使用该值我将继续进行活动。请告诉我们如何克服这个问题。