3
我是Asynctask編碼的新手，並且遇到一些問題。如何在asynctask類中等待，直到其任務完成
在我的代碼中，我在onClick偵聽器中定義了一個子類，並且在那個類中我創建了一個使用HTTP連接的Asynctask，並且有一些XML解析代碼。問題是，當我點擊我的按鈕時，它不會等待異步任務完成，而是會出現一個錯誤，提示「在主類中出現偏離」。沒有機會處理我的PostExecute，因爲異步任務中的XML解析引發了一個異常，如：「NetworkOnMainThread」。
我真的可以使用一些幫助揭開我的錯誤，這裏是我的代碼：
public class GetDirectoryInfoXMLParser {
public static ArrayList<GetDirectoryInfoTableContent> tableContent;
private GetDirectoryInfoTableContent table;
private Thread alertThread;
private ProgressDialog progressDialog;
Context context;
InputStream is;
public GetDirectoryInfoXMLParser(SettingsPage settings) {
this.context = settings;
}
public void getDataFromUrl(String webSite) throws XmlPullParserException,
IOException {
if (webSite != null) {
alert(context);
GetDirectoryInfoAsyncTask gDirectoryInfoAsyncTask = new GetDirectoryInfoAsyncTask();
gDirectoryInfoAsyncTask.execute(webSite);
} else {
}
}
private class GetDirectoryInfoAsyncTask extends
AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(
"http://mobile.primemrm.com/mobile.asmx/GetDirectoryInfo");
ProtocolVersion protocolVersion = post.getProtocolVersion();
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(1);
nameValuePairs.add(new BasicNameValuePair("sUrl", params[0]));
try {
post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse httpResponse = client.execute(post);
HttpEntity entity = httpResponse.getEntity();
is = entity.getContent();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
XmlPullParserFactory factory;
try {
factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(true);
XmlPullParser parser = factory.newPullParser();
// InputStream is = getURlResponse(params[0]);
if (is == null) {
Log.e("GetDirectoryInfoXMLParser", "InputStream is Null");
return null;
}
else if (is != null) {
Log.e("GetDirectoryInfoXMLParser",
"InputStream is Not Null");
parser.setInput(new InputStreamReader(is));
}
int eventType = parser.getEventType();
String name;
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
tableContent = new ArrayList<GetDirectoryInfoTableContent>();
} else if (eventType == XmlPullParser.START_TAG) {
name = parser.getName();
if (name.equalsIgnoreCase("Table")) {
table = new GetDirectoryInfoTableContent();
/*
* for(int i = 0; i< parser.getAttributeCount();
* i++){
* if(parser.getAttributeName(i).equalsIgnoreCase
* ("id")){
* table.setId(parser.getAttributeValue(i)); }else
* if(parser.getAttributeName(i).equalsIgnoreCase(
* "rowOrder"));
* table.setRowOrder(parser.getAttributeValue(i)); }
*/
} else if (name
.equalsIgnoreCase("EnablePublicMemberDirectory")) {
table.setEnablePublicMemberDirectory(parser
.nextText());
Log.e("GetDirectoryInfoXMLParser",
"EnablePublicMemberDirectory : "
+ table.getEnablePublicMemberDirectory());
} else if (name.equalsIgnoreCase("Response")) {
table.setEnablePublicMemberDirectory(parser
.nextText());
}
} else if (eventType == XmlPullParser.END_TAG) {
name = parser.getName();
if (name.equalsIgnoreCase("Table")) {
tableContent.add(table);
table = null;
}
}
eventType = parser.next();
}
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
}
public void alert(final Context context) {
progressDialog = ProgressDialog.show(context, "", "Loading...");
alertThread = new Thread() {
@Override
public void run() {
try {
sleep(5000);
progressDialog.dismiss();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
alertThread.start();
}
}
在此先感謝。
被修改：
verify.setOnClickListener（新OnClickListener（）{
public void onClick(View v) {
String logingString = login.getText().toString();
String passwordString = password.getText().toString();
websiteString = websiteUrl.getText().toString();
if (websiteString.equals(pref.getString(WEBSITE, null))
&& logingString.equals(pref.getString(PREF_USERNAME,
null))
&& passwordString.equals(pref.getString(PREF_PASSWORD,
null))) {
//return;
}
if (saveCredientials(logingString, passwordString,
websiteString)) {
/*Toast.makeText(getApplicationContext(),
"Saved User Name & Password", Toast.LENGTH_LONG)
.show();*/
} else {
Toast.makeText(getApplicationContext(),
"User Name (or) Password is empty",
Toast.LENGTH_LONG).show();
}
sVersion = version.getText().toString();
sWesiteUrl = websiteUrl.getText().toString();
sLogin = login.getText().toString();
sPassword = password.getText().toString();
if (sWesiteUrl == null || sWesiteUrl == ""
|| sWesiteUrl.length() == 0) {
Log.e("SettingsPage", "Jhansi check 1 sWebsite is null");
websiteNullAlertDialog();
//return;
} else if (sWesiteUrl != null) {
try {
getDirectoyrInforParser.getDataFromUrl(sWesiteUrl);
} catch (XmlPullParserException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (GetDirectoryInfoXMLParser.tableContent != null) {
if (GetDirectoryInfoXMLParser.tableContent.get(0)
.getEnablePublicMemberDirectory()
.equals("true")) {
Log.e("SettingsPage",
"Jhansi check 2 sWebsite is Public");
isLoginSucess = true;
Intent intent = new Intent(SettingsPage.this,
HomePage.class);
intent.putExtra("wesiteLogoUrl", sWesiteUrl);
startActivity(intent);
} else if (GetDirectoryInfoXMLParser.tableContent
.get(0).getEnablePublicMemberDirectory()
.equals("false")) {
Log.e("SettingsPage",
"Jhansi check 3 sWebsite is Private");
// ifMember();
if (sLogin == null || sLogin.equals("")
|| sLogin.length() == 0
|| sPassword == null
|| sPassword.equals("")
|| sPassword.length() == 0) {
Log.e("SettingsPage",
"Jhansi check 4 loging is null");
ifMember();
// m.sivajhansi
return;
// alertDialog();
}
try {
parser.getDataFromUrl(sWesiteUrl, sLogin,
sPassword);
} catch (XmlPullParserException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
if (LoginXMLParser.tableContent != null
&& LoginXMLParser.tableContent.size() > 0 && sLogin.equals(LoginXMLParser.tableContent
.get(0).getContact_email())
&& sPassword
.equals(LoginXMLParser.tableContent
.get(0)
.getContact_password())) {
Log.e("SettingsPage", "data is : "
+ LoginXMLParser.tableContent);
/*if (isLoginCorrect && sLogin.equals(LoginXMLParser.tableContent
.get(0).getContact_email())
&& sPassword
.equals(LoginXMLParser.tableContent
.get(0)
.getContact_password())) {*/
isLoginSucess = true;
Toast.makeText(SettingsPage.this,
"Login Sucess", Toast.LENGTH_SHORT)
.show();
// isLoginSucess = true;
Intent intent = new Intent(
SettingsPage.this, HomePage.class);
intent.putExtra("wesiteLogoUrl", sWesiteUrl);
startActivity(intent);
// }
/*
* else { Log.e("SettingsPage",
* "Jhansi check 5 "); alertDialog(); }
*/
}else {
Log.e("SettingsPage", "DATA CHECK");
// m.sivajhansi
alertDialog();
}
} else {
Log.e("SettingsPage", "Jhansi check 7");
websiteNullAlertDialog();
}
} else if (GetDirectoryInfoXMLParser.tableContent == null){
Log.e("SettingsPage", "Jhansi check 8");
websiteNullAlertDialog();
}
}
}
});
這就是所謂的onclick的類是：
公共類GetDirectoryInfoXMLParser {
public static ArrayList<GetDirectoryInfoTableContent> tableContent;
private GetDirectoryInfoTableContent table;
public void getDataFromUrl(String webSite)
throws XmlPullParserException, IOException {
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
factory.setNamespaceAware(true);
XmlPullParser parser = factory.newPullParser();
InputStream is = getURlResponse(webSite);
if (is == null) {
Log.e("GetDirectoryInfoXMLParser", "InputStream is Null");
return ;
}
else if (is != null) {
Log.e("GetDirectoryInfoXMLParser", "InputStream is Not Null");
parser.setInput(new InputStreamReader(is));
}
int eventType = parser.getEventType();
String name;
while (eventType != XmlPullParser.END_DOCUMENT) {
if (eventType == XmlPullParser.START_DOCUMENT) {
tableContent = new ArrayList<GetDirectoryInfoTableContent>();
}else if(eventType == XmlPullParser.START_TAG){
name = parser.getName();
if(name.equalsIgnoreCase("Table")){
table = new GetDirectoryInfoTableContent();
/*for(int i = 0; i< parser.getAttributeCount(); i++){
if(parser.getAttributeName(i).equalsIgnoreCase("id")){
table.setId(parser.getAttributeValue(i));
}else if(parser.getAttributeName(i).equalsIgnoreCase("rowOrder"));
table.setRowOrder(parser.getAttributeValue(i));
}*/
}else if(name.equalsIgnoreCase("EnablePublicMemberDirectory")){
table.setEnablePublicMemberDirectory(parser.nextText());
Log.e("GetDirectoryInfoXMLParser", "EnablePublicMemberDirectory : "+table.getEnablePublicMemberDirectory());
} else if(name.equalsIgnoreCase("Response")){
table.setEnablePublicMemberDirectory(parser.nextText());
}
}else if(eventType == XmlPullParser.END_TAG){
name = parser.getName();
if(name.equalsIgnoreCase("Table")){
tableContent.add(table);
table = null;
}
}
eventType = parser.next();
}
}
public InputStream getURlResponse(String webSite) {
InputStream is = null;
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost(
"http://mobile.primemrm.com/mobile.asmx/GetDirectoryInfo");
ProtocolVersion protocolVersion = post.getProtocolVersion();
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(1);
nameValuePairs
.add(new BasicNameValuePair("sUrl", webSite));
try {
post.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse httpResponse = client.execute(post);
HttpEntity entity = httpResponse.getEntity();
is = entity.getContent();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return is;
}
}
現在，這是我的代碼可以正常使用upto2.3.3，strictMode的東陽我得到了「NetworkOnMainThread」 ..所以請從這個地獄通過給我一些大綱處理this..Thanks幫助..
感謝Hades ..但我的問題仍然存在.. – Prasad
你可以改變你現有的代碼到我描述和發佈你的代碼的方式嗎？ – Hades
是的我changed.but它不工作，因爲需要..你可以告訴我有什麼辦法來處理在UI線程上的網絡調用，除了Asynctask方法..我在這裏掙扎從這麼多天... – Prasad