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Android:Cannot access android.os.AsyncTask.WorkRunnable

private final WorkerRunnable<Params, Result> mWorker;
private static abstract class WorkerRunnable<Params, Result> implements Callable<Result> {
Params[] mParams;
}
I take red line in mWorker = new WorkerRunnable<Params, Result>() row.This is java own class.I don't understand how can i take error.Please help me.
public AsyncTask(Looper callbackLooper) {
mHandler = callbackLooper == null || callbackLooper == Looper.getMainLooper()
? getMainHandler()
: new Handler(callbackLooper);
mWorker = new WorkerRunnable<Params, Result>() {
public Result call() throws Exception {
mTaskInvoked.set(true);
Result result = null;
try {
Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND);
//noinspection unchecked
result = doInBackground(mParams);
Binder.flushPendingCommands();
} catch (Throwable tr) {
mCancelled.set(true);
throw tr;
} finally {
postResult(result);
}
return result;
}
};
I called execute in oncreate() method like this
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_solution);
resultt = findViewById(R.id.recognizeResult2);
resultview = findViewById(R.id.textView);
new WolframFeed().execute();
}
and I use AsyncTask like this
private class WolframFeed extends AsyncTask<Void, Void, String> {
private WAException exception;
#Override
protected String doInBackground(Void... params) {
String result="";
inputText = "solve " +resultt.getText().toString();
try {
Log.e("TRYing", "wolfram try/");
WAEngine engine = new WAEngine();
engine.setAppID(APP_ID);
//engine.addPodState("Result__Step-by-step solution");
engine.addFormat("plaintext");
WAQuery query = engine.createQueryFromURL(createFullURL());
/*WAQuery query = engine.createQuery();
query.setInput(inputText);*/
WAQueryResult queryResult = engine.performQuery(query);
if (queryResult.isError()) {
String err= "Query error" + " error code: " + queryResult.getErrorCode() + " error message: " + queryResult.getErrorMessage();
Log.e("err: ",err);
} else if (!queryResult.isSuccess()) {
Log.e("err: " ,"Query was not understood; no results available.");
} else {
// Got a result.
Log.e("err: ","Successful query. Pods follow:\n");
for (WAPod pod : queryResult.getPods()) {
if (!pod.isError()) {
result+="\n";
for (WASubpod subpod : pod.getSubpods()) {
for (Object element : subpod.getContents()) {
if (element instanceof WAPlainText) {
if(((WAPlainText) element).getText()!=""){
result+=pod.getTitle();
result+= ((WAPlainText) element).getText();
result+="\n";
}
}
}
}
}
}
}
} catch (WAException e) {
e.printStackTrace();
}
return result;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
resultview.setText(result);
}
}
Please help me where am i making a mistake.

NetworkOnMainThreadException but Using AsyncTask

I coded a class which starts a http connection for getting the text of e.g. website.
I used AsyncTask but I got NetworkOnMainException. May u help me?
The class
public class getXMLData extends AsyncTask<String, Void, String> {
TextView _textview;
public getXMLData(TextView textview) {
_textview = textview;
}
protected String doInBackground(String... url)
{
String _text = "";
try {
try {
URL _url = new URL(url[0]);
HttpURLConnection con = (HttpURLConnection) _url.openConnection();
_text = readStream(con.getInputStream());
}
catch (Exception e) {
e.printStackTrace();
}
}
catch (Exception e) {
e.printStackTrace();
}
return _text;
}
protected void onPostExecute(String result)
{
_textview.setText(result.toCharArray(), 0, result.length());
}
private String readStream(java.io.InputStream in) {
java.io.BufferedReader reader = null;
String result = "";
reader = new BufferedReader(new InputStreamReader(in));
try {
while ((reader.readLine() != null)) {
result = result + reader.readLine();
}
}
catch (java.io.IOException i)
{
}
finally
{
try {
reader.close();
}
catch (java.io.IOException e) {
e.printStackTrace();
}
}
return result;
}
Here how I start the AsyncTask:
bu_aktualize.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
_getXMLData.doInBackground("http://www.google.de");
}
});
Thanks for your help.

You do not call doInBackground() yourself. Instead, you call execute() or executeOnExecutor() to start the AsyncTask.
You may wish to review the documentation for AsyncTask, which shows an example of setting up an AsyncTask, including a call to execute().

Unable to establish socket connect between two different android devices at different locations with different service providers

I am trying to establish a socket connection between two different devices at different places. I am using Airtel SIM on my android device. I am running following code on the device:
public class MainActivity extends Activity
{
Context context;
TextView info, infoip, msg;
String message = "";
ServerSocket serverSocket;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = this;
Sql s = new Sql(context);
info = (TextView) findViewById(R.id.info);
infoip = (TextView) findViewById(R.id.infoip);
msg = (TextView) findViewById(R.id.msg);
new GetPublicIPTask().execute();
}
private class SocketServerThread extends Thread
{
static final int SocketServerPORT = 8080;
int count = 0;
#Override
public void run()
{
try
{
serverSocket = new ServerSocket(SocketServerPORT);
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
info.setText("Port: " + serverSocket.getLocalPort());
}
});
while (true)
{
Socket socket = null;
try
{
socket = serverSocket.accept();
}
catch (Exception e)
{
e.printStackTrace();
}
count++;
message += "#" + count + " from " + socket.getInetAddress() + ":" + socket.getPort() + "\n";
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
msg.setText(message);
}
});
SocketServerReplyThread socketServerReplyThread = new SocketServerReplyThread(socket, count);
socketServerReplyThread.run();
}
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
private class SocketServerReplyThread extends Thread
{
private Socket hostThreadSocket;
int cnt;
SocketServerReplyThread(Socket socket, int c)
{
hostThreadSocket = socket;
cnt = c;
}
#Override
public void run()
{
OutputStream outputStream;
String msgReply = "Hello client " + cnt;
try
{
outputStream = hostThreadSocket.getOutputStream();
PrintStream printStream = new PrintStream(outputStream);
printStream.print(msgReply);
printStream.close();
message += "replied: " + msgReply + "\n";
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
msg.setText(message);
}
});
}
catch (IOException e)
{
e.printStackTrace();
message += "Exception! " + e.toString() + "\n";
}
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
msg.setText(message);
}
});
}
}
public class GetPublicIPTask extends AsyncTask<String, Integer, String>
{
ProgressDialog progressDialog;
String serverResponse = "";
public GetPublicIPTask()
{
progressDialog = new ProgressDialog(context);
}
#Override
protected void onPreExecute()
{
if (!NetWorkInfo.isOnline(context))
{
Toast.makeText(context, "No Internet Connection", Toast.LENGTH_LONG).show();
return;
}
progressDialog.setMessage("Getting IP");
progressDialog.setCancelable(false);
progressDialog.show();
}
#Override
protected String doInBackground(String... sUrl)
{
BufferedReader in = null;
int TIME_OUT = 1000 * 60 * 10;
HttpClient httpclient = new DefaultHttpClient();
HttpParams params = httpclient.getParams();
HttpConnectionParams.setConnectionTimeout(params, TIME_OUT);
HttpConnectionParams.setSoTimeout(params, TIME_OUT);
HttpGet httppost = new HttpGet("http://checkip.dyndns.org");
httppost.setHeader("Content-Type", "application/json");
try
{
HttpResponse response = httpclient.execute(httppost);
in = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
StringBuffer sb = new StringBuffer("");
String line = "";
while ((line = in.readLine()) != null)
{
sb.append(line);
}
serverResponse = sb.toString();
return serverResponse;
}
catch (Exception ex)
{
Log.d("Socket Server", "StackTrace : " + ex.getStackTrace().toString());
}
finally
{
try
{
if (in != null)
{
in.close();
}
}
catch (IOException e)
{
throw new RuntimeException(e);
}
}
return null;
}
#Override
protected void onPostExecute(String result)
{
if (progressDialog != null && progressDialog.isShowing())
{
progressDialog.dismiss();
}
infoip.setText(serverResponse);
Thread socketServerThread = new Thread(new SocketServerThread());
socketServerThread.start();
super.onPostExecute(result);
}
}
}
And from terminal I am hitting the mobile app:
telnet publicIpAddress 8080
Same process working in local network, but not working in mobile networks.

how to add runOnUiThread() in my Activity

I added the AsyncTask to offload network operations to a background thread.I need to make sure the UI operations are on the UI thread.So i want to Use runOnUiThread() in my Activity.
Thanks for your help
WifiApManager
public class WifiApManager {
private final WifiManager mWifiManager;
public WifiApManager(Context context) {
mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
}
public boolean setWifiApEnabled(WifiConfiguration wifiConfig, boolean enabled) {
try {
if (enabled) { // disable WiFi in any case
mWifiManager.setWifiEnabled(false);
}
Method method = mWifiManager.getClass().getMethod("setWifiApEnabled", WifiConfiguration.class, boolean.class);
return (Boolean) method.invoke(mWifiManager, wifiConfig, enabled);
} catch (Exception e) {
Log.e(this.getClass().toString(), "wifi", e);
return false;
}
}
public WIFI_AP_STATE getWifiApState() {
try {
Method method = mWifiManager.getClass().getMethod("getWifiApState");
int tmp = ((Integer)method.invoke(mWifiManager));
// Fix for Android 4
if (tmp > 10) {
tmp = tmp - 10;
}
return WIFI_AP_STATE.class.getEnumConstants()[tmp];
} catch (Exception e) {
Log.e(this.getClass().toString(), "wifi", e);
return WIFI_AP_STATE.WIFI_AP_STATE_FAILED;
}
}
public boolean isWifiApEnabled() {
return getWifiApState() == WIFI_AP_STATE.WIFI_AP_STATE_ENABLED;
}
public WifiConfiguration getWifiApConfiguration() {
try {
Method method = mWifiManager.getClass().getMethod("getWifiApConfiguration");
return (WifiConfiguration) method.invoke(mWifiManager);
} catch (Exception e) {
Log.e(this.getClass().toString(), "wifi", e);
return null;
}
}
public boolean setWifiApConfiguration(WifiConfiguration wifiConfig) {
try {
Method method = mWifiManager.getClass().getMethod("setWifiApConfiguration", WifiConfiguration.class);
return (Boolean) method.invoke(mWifiManager, wifiConfig);
} catch (Exception e) {
Log.e(this.getClass().toString(), "wifi", e);
return false;
}
}
public ArrayList<ClientScanResult> getClientList(boolean onlyReachables) {
return getClientList(onlyReachables, 10);
}
public ArrayList<ClientScanResult> getClientList(boolean onlyReachables, int reachableTimeout) {
BufferedReader br = null;
ArrayList<ClientScanResult> result = null;
try {
result = new ArrayList<ClientScanResult>();
br = new BufferedReader(new FileReader("/proc/net/arp"));
String line;
while ((line = br.readLine()) != null) {
String[] splitted = line.split(" +");
if ((splitted != null) && (splitted.length >= 4)) {
// Basic sanity check
String mac = splitted[3];
if (mac.matches("..:..:..:..:..:..")) {
boolean isReachable = InetAddress.getByName(splitted[0]).isReachable(reachableTimeout);
if (!onlyReachables || isReachable) {
result.add(new ClientScanResult(splitted[0], splitted[3], splitted[5], isReachable));
}
}
}
}
} catch (Exception e) {
Log.e(LOGTAG, e.toString());
} finally {
try {
br.close();
} catch (IOException e) {
Log.e(LOGTAG, e.toString());
}
}
return result;
}
}
connect.java
public class connect extends Activity{
WifiApManager wifiApManager;
TextView tv;
Button scan;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.connect);
tv =(TextView) findViewById(R.id.iptv);
new scan().execute();
}
public class scan extends AsyncTask<String, Integer, String> {
public Object WIFI_SERVICE;
#Override
protected void onProgressUpdate(Integer...integers) {
ArrayList<ClientScanResult> clients = wifiApManager.getClientList(false);
tv.setText("WifiApState: " + wifiApManager.getWifiApState() + "\n\n");
tv.append("Clients: \n");
for (ClientScanResult clientScanResult : clients) {
tv.append("####################\n");
tv.append("IpAddr: " + clientScanResult.getIpAddr() + "\n");
tv.append("Device: " + clientScanResult.getDevice() + "\n");
tv.append("HWAddr: " + clientScanResult.getHWAddr() + "\n");
tv.append("isReachable: " + clientScanResult.isReachable()+ "\n");
}
}
#Override
protected void onPostExecute(String result){
tv.setText(result);
}
#Override
protected String doInBackground(String... params) {
wifiApManager = new WifiApManager(this);
// the above line shows a Error
return null;
}
}
}
EDIT
I want to Display the processed text in a TextView
class scan extends AsyncTask<String, Void, Void> {
public Context context;
ArrayList<ClientScanResult> clients;
public scan(Context c) // constructor to take Context
{
context = c; // Initialize your Context variable
}
protected Void doInBackground(String... params) {
wifiApManager = new WifiApManager(context); // use the variable here
clients = wifiApManager.getClientList(false);
return null;
}
}
protected void onPostExecute(Void result){
ArrayList<ClientScanResult> clients;
tv.setText("WifiApState: " + wifiApManager.getWifiApState() + "\n\n");
tv.append("Clients: \n");
for (ClientScanResult clientScanResult : clients)//showin error in clients
{
tv.append("####################\n");
tv.append("IpAddr: " + clientScanResult.getIpAddr() + "\n");
tv.append("Device: " + clientScanResult.getDevice() + "\n");
tv.append("HWAddr: " + clientScanResult.getHWAddr() + "\n");
tv.append("isReachable: " + clientScanResult.isReachable()+ "\n");
}
}
}

I added the AsyncTask to offload network operations to a background thread.I need to make sure the UI operations are on the UI thread.So i want to Use runOnUiThread() in my Activity.
Ugh! No!!! Every method of AsyncTask runs on the UI Thread except for doInBackground(). So do your network operations in doInBackground() and update the UI in onPostExecute() or in onProgressUpdate() by calling publishProgress() from doInBackground().
Do not use runOnUiThread() with AsyncTask. There is no reason, at least known to me, to use that with AsyncTask since it has methods that already run on the UI Thread. I have never seen it do anything but cause trouble.
You can either call publishProgress() from your loop and update your TextView in onProgressUpdate() or add the values to an ArrayList and update in onProgressUpdate().
Please read the docs several times. AsyncTask is a bit tricky at first but once you learn what it does then it can be a beautiful thing.
Edit
Create an instance of your AsyncTask and pass your Activity Context to it
Scan myScan = new scan(this); // pass the context to the constructor
myScan.execute();
Then create a constructor in your AsyncTask and have it accept a Context.
public class scan extends AsyncTask<String, Integer, String>
{
public Object WIFI_SERVICE;
public Context context; // Context variable
public scan(Context c) // constructor to take Context
{
context = c; // intialize your Context variable
}
Now use that variable
#Override
protected String doInBackground(String... params)
{
wifiApManager = new WifiApManager(context); // use the variable here
return null;
}
Another Edit
class scan extends AsyncTask<String, Void, Void> {
ArrayList<ClientScanResult> clients;
Context context;
...
then initialize your `clients` in `doInBackground()`
clients = wifiApManager.getClientList(false);
change onPostExecute() to not accept anything
protected void onPostExecute(Void result){
and put your code that updates the TextView in there.

You should not be accessing any UI elements within doInBackground, This method runs in background thread. What you should do is override onPostExecute() method and access your TextView there. onPostExecute runs in UI thread, so you don't need to call runOnUiThread()

ANR force close when running this code

This code is causing ANR force close any idea how to improve this code? i try with asynctask and i cant make it work in this code :
What i try to do here is updater activity will check for latest version and if got new version it will pop up alertdialog to ask user to update in the market
public class Updater extends Activity {
private int newVerCode = 0;
private String newVerName = "";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
if (getServerVerCode()) {
int vercode = Config.getVerCode(this);
if (newVerCode > vercode) {
doNewVersionUpdate();
} else {
notNewVersionShow();
}
}
}
//check version using json
private boolean getServerVerCode() {
try {
String verjson = NetworkTool.getContent(Config.UPDATE_SERVER
+ Config.UPDATE_VERJSON);
JSONArray array = new JSONArray(verjson);
if (array.length() > 0) {
JSONObject obj = array.getJSONObject(0);
try {
newVerCode = Integer.parseInt(obj.getString("verCode"));
newVerName = obj.getString("verName");
} catch (Exception e) {
newVerCode = -1;
newVerName = "";
return false;
}
}
} catch (Exception e) {
return false;
}
return true;
}
//Found No new version
private void notNewVersionShow() {
Updater.this.finish(); // End updater activity
}
//Found New version
private void doNewVersionUpdate() {
//Display alertdialog
}
}

You can use an AsyncTask - yes. In doInBackground you can add the code from getServerVerCode() and in onPostExecute everything in the if (getServerVerCode()).
doInBackground can return boolean so you know in onPostExecute what the result is.
Something like this:
private class GetServerVerCode extends AsyncTask<Void, Void, Boolean> {
#Override
protected Boolean doInBackground(Void... params) {
try {
String verjson = NetworkTool.getContent(Config.UPDATE_SERVER
+ Config.UPDATE_VERJSON);
JSONArray array = new JSONArray(verjson);
if (array.length() > 0) {
JSONObject obj = array.getJSONObject(0);
try {
newVerCode = Integer.parseInt(obj.getString("verCode"));
newVerName = obj.getString("verName");
} catch (Exception e) {
newVerCode = -1;
newVerName = "";
return false;
}
}
} catch (Exception e) {
return false;
}
return true;
}
#Override
protected void onPostExecute(Boolean result) {
if (result) {
int vercode = Config.getVerCode(this);
if (newVerCode > vercode) {
doNewVersionUpdate();
} else {
notNewVersionShow();
}
}
}
}