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POException occurs in Async task
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10476727
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2012-05-07T04:40:32.567
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I am getting this exception. When, i'm trying to run my program. In my program i am executing an <code>AsyncTask</code> For each download and upload tasks, I have created new <code>AsyncTask</code> object and tried to run it in background. I tried to find my mistake. But i can't find where i am going wrong. Below are my stack trace and code of my program - <pre><code>05-07 10:00:44.899: E/AndroidRuntime(367): FATAL EXCEPTION: AsyncTask #1 05-07 10:00:44.899: E/AndroidRuntime(367): java.lang.RuntimeException: An error occured while executing doInBackground() 05-07 10:00:44.899: E/AndroidRuntime(367): at android.os.AsyncTask$3.done(AsyncTask.java:200) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:274) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.FutureTask.setException(FutureTask.java:125) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:308) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.FutureTask.run(FutureTask.java:138) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.lang.Thread.run(Thread.java:1019) 05-07 10:00:44.899: E/AndroidRuntime(367): Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare() 05-07 10:00:44.899: E/AndroidRuntime(367): at android.os.Handler.<init>(Handler.java:121) 05-07 10:00:44.899: E/AndroidRuntime(367): at android.widget.Toast.<init>(Toast.java:68) 05-07 10:00:44.899: E/AndroidRuntime(367): at android.widget.Toast.makeText(Toast.java:231) 05-07 10:00:44.899: E/AndroidRuntime(367): at com.android.test.Helper.downloadTask(t.java:269) 05-07 10:00:44.899: E/AndroidRuntime(367): at com.android.test.Helper.doInBackground(t.java:132) 05-07 10:00:44.899: E/AndroidRuntime(367): at com.android.test.Helper.doInBackground(t.java:1) 05-07 10:00:44.899: E/AndroidRuntime(367): at android.os.AsyncTask$2.call(AsyncTask.java:185) 05-07 10:00:44.899: E/AndroidRuntime(367): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:306) 05-07 10:00:44.899: E/AndroidRuntime(367): ... 4 more </code></pre> This is my AsynTask Helper <pre><code>class Helper extends AsyncTask<Integer, Void, Void> { private SmbFile dfile; private String dfilepath; private SmbFile dfolder; private String dfolderpath; private File ufolder; private SmbFile ufoldersmb; private NtlmPasswordAuthentication auth; private int upstate=0; private int downstate=0; private Context context; private ArrayList<SmbFile> smbArray=new ArrayList<SmbFile>(); private String ext; private int tasknumber; private String taskname; public Context getcontext() { return context; } public int gettasknumber() { return tasknumber; } public String gettaskname() { return taskname; } public int getupstate() { return upstate; } public int getdownstate() { return downstate; } public void setdfile(SmbFile a) { this.dfile = a; } public void setdfilepath(String b) { this.dfilepath = b; } public void setdfolder(SmbFile c) { this.dfolder = c; } public void setdfolderpath(String d) { this.dfolderpath = d; } public void setufolder(File g) { this.ufolder = g; } public void setufoldersmb(SmbFile h) { this.ufoldersmb = h; } public void setauthentication(NtlmPasswordAuthentication i) { this.auth = i; } public void setupstate(int j) { upstate = j; } public void setdownstate(int k) { downstate = k; } public void setcontext(Context l) { context = l; } public void setarraysmb(SmbFile m) { this.smbArray.add(m); } public void setextstorage(String n) { this.ext=n; } public void settasknumber(int o) { this.tasknumber=o; } public void settaskname(String p) { this.taskname=p; } @Override protected Void doInBackground(Integer... params) { //check flag to execute exactly method switch (params[0]) { case 0: downloadTask(); break; case 1: Toast.makeText(context, "AccessPC Upload task "+tasknumber+" Started", Toast.LENGTH_LONG).show(); uploadFolder(ufolder,ufoldersmb); break; default:break; } return null; } void downloadFile(SmbFile dfile,String dpath) { StatFs statFs = new StatFs(Environment.getExternalStorageDirectory().getAbsolutePath()); long blockSize = statFs.getBlockSize(); long freeSize = statFs.getFreeBlocks()*blockSize; try { if(!((freeSize-dfile.length())<0)) { SmbFileInputStream din=new SmbFileInputStream(dfile); FileOutputStream dout=new FileOutputStream(dpath); int c; while((c=din.read())!=-1) { dout.write(c); } if (din != null) { din.close(); } if (dout != null) { dout.close(); } } else { Toast.makeText(context, "AccessPC Download Task failed ",Toast.LENGTH_LONG).show(); } } catch(Exception e) { Toast.makeText(context, "AccessPC Download Task failed "+e,Toast.LENGTH_LONG).show(); } } void downloadFolder(SmbFile dfolder,String dfolderpath) { try { dfolderpath=dfolderpath+dfolder.getName(); if(!(new File(dfolderpath)).exists()) { (new File(dfolderpath)).mkdir(); } SmbFile[] temp=dfolder.listFiles(); if(temp.length==0) { Toast.makeText(context, "df,downstate="+downstate,Toast.LENGTH_LONG).show(); return; } for(SmbFile m:temp) { if(m.isFile()) { downloadFile(m,dfolderpath+m.getName()); } else { downloadFolder(m,dfolderpath); } } } catch (Exception e) { Toast.makeText(context, "AccessPC Download Task failed "+e,Toast.LENGTH_LONG).show(); } } void uploadFile(File ufile,SmbFile ufilesmb) { try { FileInputStream uin=new FileInputStream(ufile); SmbFile tempSmb=new SmbFile(ufilesmb.getPath()+ufile.getName(),auth); SmbFileOutputStream uout=new SmbFileOutputStream(tempSmb); int c; while((c=uin.read())!=-1) { uout.write(c); } if (uin != null) { uin.close(); } if (uout != null) { uout.close(); } } catch(Exception e) { Toast.makeText(context, "AccessPC Upload Task failed "+e, Toast.LENGTH_LONG).show(); } } void uploadFolder(File ufolder,SmbFile ufoldersmb) { try { SmbFile tempSmb=new SmbFile(ufoldersmb.getPath()+ufolder.getName()+"/",auth); if(!tempSmb.exists()) { tempSmb.mkdir(); } File[] ftemp=ufolder.listFiles(); if(ftemp.length==0) { setupstate(2); return; } for(File m:ftemp) { if(m.isFile()) { uploadFile(m,tempSmb); } else { uploadFolder(m,tempSmb); } } } catch (Exception e) { Toast.makeText(context, "AccessPC Upload Task failed "+e,Toast.LENGTH_LONG).show(); } } void downloadTask() { Toast.makeText(context, "AccessPC download task "+tasknumber+" Started", Toast.LENGTH_LONG).show(); try { for(SmbFile m:smbArray) { if(m.isFile()) { setdfile(m); setdfilepath(ext+m.getName()); downloadFile(dfile,dfilepath); } else { setdfolder(m); setdfolderpath(ext); downloadFolder(dfolder,dfolderpath); } } setdownstate(2); } catch (Exception e) { Toast.makeText(context,"Download error "+e,Toast.LENGTH_LONG).show(); } } @Override protected void onPostExecute(Void result) { if(upstate==2) { setupstate(0); Toast.makeText(context, "AccessPC "+taskname+" task "+tasknumber+" Finished", Toast.LENGTH_LONG).show(); } if(downstate==2) { setdownstate(0); Toast.makeText(context, "AccessPC "+taskname+" task "+tasknumber+" Finished", Toast.LENGTH_LONG).show(); } } } </code></pre> This is my options menu. I ve used this to do my asyn task variable i have used in my main activity which helps this task: <pre><code>String extStorage=Environment.getExternalStorageDirectory()+"/t/"; ArrayList<Helper> helpobject=new ArrayList<Helper>(); int uptask=0; int downtask=0; public boolean onOptionsItemSelected(MenuItem item) { switch(item.getItemId()) { case DOWNLOAD1: MENU_STATE=MENU_DOWNLOAD; map=display_check(current); return true; case UPLOAD: if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { if(current.getShare()==null) { Toast.makeText(this,"UPLOAD FAILED",Toast.LENGTH_LONG).show(); } else { File f=new File(extStorage); Helper help=new Helper(); help.setufolder(f); help.setufoldersmb(current); help.setauthentication(auth); help.setupstate(1); help.settasknumber(uptask); uptask++; help.settaskname("Upload"); help.setcontext(this.getApplicationContext()); help.execute(1); } } else { Toast.makeText(this,"UPLOAD FAILED--NO SD CARD FOUND",Toast.LENGTH_LONG).show(); } return true; case DELETE1: MENU_STATE=MENU_DELETE; map=display_check(current); return true; case QUIT: int x=0; for(Helper k:helpobject) { if(k.getStatus().equals(AsyncTask.Status.RUNNING)||k.getStatus().equals(AsyncTask.Status.RUNNING)) { Toast.makeText(k.getcontext(), "AccessPC "+k.gettaskname()+" "+k.gettasknumber()+" Cancelled", Toast.LENGTH_SHORT).show(); k.cancel(true); } helpobject.remove(x); x++; } return true; case DOWNLOAD2: if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { int tempcount=0; for(int i=0;i<object.getCount();i++) { if(object.getter(i)==true) { tempcount++; } } if(tempcount==0) { Toast.makeText(this,"Please choose atleast one item for download!!",Toast.LENGTH_LONG).show(); } else { Helper help=new Helper(); helpobject.add(help); help.settasknumber(downtask); downtask++; help.settaskname("Download"); help.setcontext(this.getApplicationContext()); help.setextstorage(extStorage); help.setdownstate(1); for(int i=0;i<object.getCount();i++) { if(object.getter(i)==true) { help.setarraysmb(map.get(object.getItem(i))); } } help.execute(0); } } else { Toast.makeText(this,"DOWNLOAD FAILED--NO SD CARD FOUND",Toast.LENGTH_LONG).show(); } return true; case DELETE2: for(int i=0;i<object.getCount();i++) { if(object.getter(i)==true) { try { map.get(object.getItem(i)).delete(); } catch (Exception e) { Toast.makeText(this,"cannot be deleted "+e,Toast.LENGTH_LONG).show(); } } } return true; case CANCEL: MENU_STATE=MENU_GENERAL; map=display(current); return true; case FINISH: finish(); default: return super.onOptionsItemSelected(item); } } </code></pre> hi,when i tried to display the toast, as mentioned in one of the below comments, ive got the same exception .please see the code below whih i ve used to dispaly Toast in my async task: <pre><code>(new Activity()).runOnUiThread(new Runnable(){@Override public void run() {//Your Toast Toast.makeText(context, "AccessPC Download Task failed ",Toast.LENGTH_LONG).show(); }}); </code></pre> Do i need to make any changes to my async task code or options menu code? I ve used handler like this: <pre><code>public Handler handler = new Handler() { public void handleMessage(Message msg) { Bundle b = msg.getData(); String key = b.getString(null); Toast.makeText(getApplicationContext(),key, Toast.LENGTH_SHORT).show(); } }; </code></pre> and i am calling handler like this: <pre><code>Message msg = new Message(); Bundle b = new Bundle(); b.putString(null, "AccessPC "+taskname+" task "+tasknumber+" Finished"); msg.setData(b); //this is error t.handler.sendMessage(msg); </code></pre> But how can i call a non-static method?do i need to create an object for my main class(class t extends list activity)? Hi, please see another exception that ive got when i select 'QUIT' operation from options menu for the above async task and menu ive posted. how to avoid this exception: <pre><code>05-07 16:24:07.573: E/AndroidRuntime(13466): FATAL EXCEPTION: main 05-07 16:24:07.573: E/AndroidRuntime(13466): java.util.ConcurrentModificationException 05-07 16:24:07.573: E/AndroidRuntime(13466): at java.util.ArrayList$ArrayListIterator.next(ArrayList.java:576) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.test.t.onOptionsItemSelected(t.java:622) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.app.Activity.onMenuItemSelected(Activity.java:2205) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:748) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:143) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:855) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.view.menu.IconMenuView.invokeItem(IconMenuView.java:532) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.view.menu.IconMenuItemView.performClick(IconMenuItemView.java:122) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.view.View$PerformClick.run(View.java:9080) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.os.Handler.handleCallback(Handler.java:587) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.os.Handler.dispatchMessage(Handler.java:92) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.os.Looper.loop(Looper.java:123) 05-07 16:24:07.573: E/AndroidRuntime(13466): at android.app.ActivityThread.main(ActivityThread.java:3683) 05-07 16:24:07.573: E/AndroidRuntime(13466): at java.lang.reflect.Method.invokeNative(Native Method) 05-07 16:24:07.573: E/AndroidRuntime(13466): at java.lang.reflect.Method.invoke(Method.java:507) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 05-07 16:24:07.573: E/AndroidRuntime(13466): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 05-07 16:24:07.573: E/AndroidRuntime(13466): at dalvik.system.NativeStart.main(Native Method) </code></pre>
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Exception occurs in Async task
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