请遵循以下代码我不明白为什么它没有加载数据。以下活动是在启动活动后开始的。在这里我试图从服务器和放大器下载数据解析它＆amp;尝试将它附加到微调器，但它强制关闭应用程序说第1行没有找到元素，所以我不知道为什么它不起作用...
编辑：---代码正在开发android 2.3＆amp;以上但不是Android 2.2最低sdk版本要求是8（Android 2.2）
public class Registration extends Activity{
private List<RegisterMessage> regis_msg;
private List<CountryMessage> country_msg;
ArrayList<String> countryName,countryCode,isoCode,countryFlag;
EditText fname,sname,email,mobileno;
Spinner country;
AppPreferences ap;
Button btnregister;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.registration);
country = (Spinner)findViewById(R.id.country);
fname = (EditText)findViewById(R.id.fname);
sname = (EditText)findViewById(R.id.sname);
email = (EditText)findViewById(R.id.email);
mobileno = (EditText)findViewById(R.id.mobileno);
ap = new AppPreferences(getApplicationContext());
// mobileno.setText(ap.getPreferences("MobileNo"));
btnregister = (Button)findViewById(R.id.btnregister);
btnregister.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if(fname.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Please Enter Firstname.", Toast.LENGTH_SHORT).show();
fname.setFocusable(true);
fname.requestFocus();
}else if (sname.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Please Enter Surname.", Toast.LENGTH_SHORT).show();
sname.setFocusable(true);
sname.requestFocus();
}else if (email.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Please Enter Email address.", Toast.LENGTH_SHORT).show();
email.setFocusable(true);
email.requestFocus();
}else if (mobileno.getText().toString().equals("")){
Toast.makeText(getApplicationContext(), "Please Enter Mobile No.", Toast.LENGTH_SHORT).show();
email.setFocusable(true);
email.requestFocus();
}else{
new RegistrationTry().execute();
}
}
});
if(!isOnline()) {
Log.v("isOnline",isOnline()+"");
Toast.makeText(getApplicationContext(), "You device is not connected to the internet.",Toast.LENGTH_LONG).show();
}else{
new CountryData().execute();
}
}
public boolean isOnline(){
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
boolean isconnected;
if (netInfo==null || !netInfo.isConnected())
isconnected=false;
else
isconnected=true;
Log.v("isOnliNe",isconnected+"");
return isconnected;
}
class CountryData extends AsyncTask<Object, Object, Object> {
// private CustomizeDialog Dialog = new CustomizeDialog(Registration.this);
private ProgressDialog Dialog = new ProgressDialog(Registration.this);
@Override
protected void onPreExecute() {
Dialog.setMessage("Loading please wait........");
Dialog.show();
}
protected Void doInBackground(Object...params) {
try{
String url= newsReaderUrls.BASE_URL + newsReaderUrls.COUNTRY_URL;
Log.v("URL",url);
BaseFeedParser parser = new BaseFeedParser(url);
country_msg = parser.CountryParse();
countryName = new ArrayList<String>();
countryCode = new ArrayList<String>();
isoCode = new ArrayList<String>();
countryFlag = new ArrayList<String>();
countryName.add(0, "Select");
for (CountryMessage msg : country_msg){
countryName.add(msg.getCountryName());
countryCode.add(msg.getCountryCode());
isoCode.add(msg.getIsoCode());
countryFlag.add(msg.getCountryFlag());
}
} catch (Throwable t){
Log.e("AndroidNews",t.getMessage(),t);
}
return null;
}
protected void onProgressUpdate(Object... values){
// TODO Auto-generated method stub
super.onProgressUpdate(values);
}
@Override
protected void onPostExecute(Object result) {
if(Dialog.isShowing()){
Dialog.dismiss();
}
String[] array_spinner = countryName.toArray(new String[countryName.size()]);
ArrayAdapter<String> adapter = new ArrayAdapter<String> (getApplicationContext(),android.R.layout.simple_spinner_item,array_spinner);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
country.setAdapter(adapter);
String cn = ap.getPreferences("CountryIso");
if(!cn.equals("")){
int index = isoCode.indexOf(cn);
country.setSelection(index+1);
}else if(countryName.indexOf("Nigeria") != -1){
country.setSelection(countryName.indexOf("Nigeria")+1);
}
}
}
class RegistrationTry extends AsyncTask<Void, Void, Void> {
// private CustomizeDialog Dialog = new CustomizeDialog(Registration.this);
private ProgressDialog Dialog = new ProgressDialog(Registration.this);
int foreward;
@Override
protected void onPreExecute() {
Dialog.setMessage("Loading please wait........");
Dialog.show();
}
protected void onProgressUpdate(Void... unused) {
}
protected Void doInBackground(Void...params) {
try{
String defaultC_code="ng";
/*if(countryName.size()<0){
defaultC_code = "ng";
}else{
int index = country.getSelectedItemPosition();
defaultC_code = isoCode.get(index-1);
}*/
ap.savePreferences("MobileNo", mobileno.getText().toString());
String url= newsReaderUrls.BASE_URL + newsReaderUrls.REGISTER_URL + "Mobile="+ mobileno.getText().toString()+
"&First_Name="+fname.getText().toString()+"&Last_Name="+sname.getText().toString()+
"&Email="+email.getText().toString()+"&Device_Type=Phone&Device_Platform=Android"+
"&ISO_Code=" + defaultC_code;
Log.v("Login", url);
BaseFeedParser parser = new BaseFeedParser(url);
regis_msg = parser.RegisterParse();
for (RegisterMessage msg : regis_msg){
Log.v("Status", msg.getStatus());
foreward = Integer.parseInt(msg.getStatus());
}
} catch (Throwable t){
Log.e("AndroidNews",t.getMessage(),t);
}
return null;
}
@Override
protected void onPostExecute(Void result) {
if(foreward == 2 || foreward == 3){
ap.savePreferences("Registered", "yes");
Intent i = new Intent(Registration.this,DashBoard.class);
startActivity(i);
finish();
}else{
Toast.makeText(getBaseContext(), "Registration failed please try later.", Toast.LENGTH_SHORT).show();
}
if(Dialog.isShowing()){
Dialog.dismiss();
}
}
}
}
LogCat
10-31 16:13:41.022: ERROR/AndroidNews(599): org.apache.harmony.xml.ExpatParser$ParseException: At line 1, column 0: no element found
10-31 16:13:41.022: ERROR/AndroidNews(599): java.lang.RuntimeException: org.apache.harmony.xml.ExpatParser$ParseException: At line 1, column 0: no element found
10-31 16:13:41.022: ERROR/AndroidNews(599): at com.websoft.android.parser.BaseFeedParser.CountryParse(BaseFeedParser.java:189)
10-31 16:13:41.022: ERROR/AndroidNews(599): at com.websoft.android.newsreel.Registration$CountryData.doInBackground(Registration.java:117)
10-31 16:13:41.022: ERROR/AndroidNews(599): at com.websoft.android.newsreel.Registration$CountryData.doInBackground(Registration.java:1)
10-31 16:13:41.022: ERROR/AndroidNews(599): at android.os.AsyncTask$2.call(AsyncTask.java:185)
10-31 16:13:41.022: ERROR/AndroidNews(599): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
10-31 16:13:41.022: ERROR/AndroidNews(599): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
10-31 16:13:41.022: ERROR/AndroidNews(599): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
10-31 16:13:41.022: ERROR/AndroidNews(599): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
10-31 16:13:41.022: ERROR/AndroidNews(599): at java.lang.Thread.run(Thread.java:1096)
10-31 16:13:41.022: ERROR/AndroidNews(599): Caused by: org.apache.harmony.xml.ExpatParser$ParseException: At line 1, column 0: no element found
10-31 16:13:41.022: ERROR/AndroidNews(599): at org.apache.harmony.xml.ExpatParser.finish(ExpatParser.java:553)
10-31 16:13:41.022: ERROR/AndroidNews(599): at org.apache.harmony.xml.ExpatParser.parseDocument(ExpatParser.java:483)
10-31 16:13:41.022: ERROR/AndroidNews(599): at org.apache.harmony.xml.ExpatReader.parse(ExpatReader.java:320)
10-31 16:13:41.022: ERROR/AndroidNews(599): at org.apache.harmony.xml.ExpatReader.parse(ExpatReader.java:277)
10-31 16:13:41.022: ERROR/AndroidNews(599): at android.util.Xml.parse(Xml.java:87)
10-31 16:13:41.022: ERROR/AndroidNews(599): at com.websoft.android.parser.BaseFeedParser.CountryParse(BaseFeedParser.java:187)
10-31 16:13:41.022: ERROR/AndroidNews(599): ... 8 more
10-31 16:13:41.022: DEBUG/AndroidRuntime(599): Shutting down VM
10-31 16:13:41.042: WARN/dalvikvm(599): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): FATAL EXCEPTION: main
10-31 16:13:41.042: ERROR/AndroidRuntime(599): java.lang.NullPointerException
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at com.websoft.android.newsreel.Registration$CountryData.onPostExecute(Registration.java:140)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.os.AsyncTask.finish(AsyncTask.java:417)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.os.AsyncTask.access$300(AsyncTask.java:127)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:429)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.os.Handler.dispatchMessage(Handler.java:99)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.os.Looper.loop(Looper.java:123)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at android.app.ActivityThread.main(ActivityThread.java:4627)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at java.lang.reflect.Method.invokeNative(Native Method)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at java.lang.reflect.Method.invoke(Method.java:521)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-31 16:13:41.042: ERROR/AndroidRuntime(599): at dalvik.system.NativeStart.main(Native Method)
答案 0 :(得分：1)
当你做country_msg = parser.CountryParse();时有一个解析异常ExpatParser$ParseException。
在第1行第0列：找不到元素
这意味着该文件为空。
因此countryName , countryCode , isoCode都是null，因此postExecute()中的CountryData中的NPE。
查看此字符串newsReaderUrls.BASE_URL + newsReaderUrls.COUNTRY_URL，当放入浏览器时返回有效的URL和正确的xml
答案 1 :(得分：0)
如果您无法从设备访问，URL是否可以位于内部网络中？另外，您是否将结果放在XML解析器/验证器中？