java - Android, Using an Async task to grab text from url -

right think far goes should consider me complete noob, in way on head.

i have attempted cobble understand several partial tutorials each dealing different aspect want do.

long , short of it, want text read url display in text view, understanding need asynctask since 3.0 update.

any on going wrong great don't understand what's causing error , how fix.

i know code contained within try , catch of doinbackground works on own before 3.0 update. whether needs modified work async don't know.

i imagine other issues arise once 1 sorted, if spots glaringly obvious grateful if point out.

string event; textview eventtext; textview titletext;  string html;  public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.newevent);      titletext = (textview) findviewbyid(r.id.title);     eventtext = (textview) findviewbyid(r.id.event);      new eventupdate().execute();   }  public class eventupdate extends asynctask<string, void, void> {      @override     protected void doinbackground(string... url) {          try {              thread.sleep(4000);                               httpclient httpclient = new defaulthttpclient();             httpcontext localcontext = new basichttpcontext();             httpget httpget = new httpget(                     "http://masterzangetsu.eu/apps/rocksoctest"); // url!             httpresponse response = httpclient.execute(httpget,                     localcontext);             string result = "";              bufferedreader reader = new bufferedreader(                     new inputstreamreader(response.getentity().getcontent()));              string line = null;             while ((line = reader.readline()) != null) {                 result += line + "\n";                 html = result;             }          } catch (interruptedexception e) {              e.printstacktrace();           } catch (clientprotocolexception e) {             // todo auto-generated catch block             e.printstacktrace();         } catch (ioexception e) {             // todo auto-generated catch block             e.printstacktrace();         }          eventtext.settext("" + html);          // todo auto-generated method stub         return null;     }   } 

and logcat error is:

w/dalvikvm(394): threadid=9: thread exiting uncaught exception (group=0x40015560) e/androidruntime(394): fatal exception: asynctask #1 e/androidruntime(394): java.lang.runtimeexception: error occured while executing doinbackground() e/androidruntime(394):  @ android.os.asynctask$3.done(asynctask.java:200) e/androidruntime(394):  @ java.util.concurrent.futuretask$sync.innersetexception(futuretask.java:274) e/androidruntime(394):  @ java.util.concurrent.futuretask.setexception(futuretask.java:125) e/androidruntime(394):  @ java.util.concurrent.futuretask$sync.innerrun(futuretask.java:308) e/androidruntime(394):  @ java.util.concurrent.futuretask.run(futuretask.java:138) e/androidruntime(394):  @ java.util.concurrent.threadpoolexecutor.runworker(threadpoolexecutor.java:1088) e/androidruntime(394):  @ java.util.concurrent.threadpoolexecutor$worker.run(threadpoolexecutor.java:581) e/androidruntime(394):  @ java.lang.thread.run(thread.java:1019)  e/androidruntime(394): caused by: android.view.viewroot$calledfromwrongthreadexception: original thread created view hierarchy can touch views.  e/androidruntime(394):  @ android.view.viewroot.checkthread(viewroot.java:2932) e/androidruntime(394):  @ android.view.viewroot.requestlayout(viewroot.java:629) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.widget.scrollview.requestlayout(scrollview.java:1291) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.widget.relativelayout.requestlayout(relativelayout.java:257) e/androidruntime(394):  @ android.view.view.requestlayout(view.java:8267) e/androidruntime(394):  @ android.widget.textview.checkforrelayout(textview.java:5521) e/androidruntime(394):  @ android.widget.textview.settext(textview.java:2724) e/androidruntime(394):  @ android.widget.textview.settext(textview.java:2592) e/androidruntime(394):  @ android.widget.textview.settext(textview.java:2567) e/androidruntime(394):  @ com.masterzangetsu.kentrocksoc.nextevent$eventupdate.doinbackground(nextevent.java:81) e/androidruntime(394):  @ com.masterzangetsu.kentrocksoc.nextevent$eventupdate.doinbackground(nextevent.java:1) e/androidruntime(394):  @ android.os.asynctask$2.call(asynctask.java:185) e/androidruntime(394):  @ java.util.concurrent.futuretask$sync.innerrun(futuretask.java:306) 

this line here

 eventtext.settext("" + html); 

is causing problem. can't update ui doinbackground(). has done in 1 of other methods or sent main activity method. here in onpostexecute()

read through aynctask docs

there different ways of accomplishing change asynctask return result onpostexecute()

public class eventupdate extends asynctask<string, void, string> // change last param 

then add onpostexecute() method , change return statement in doinbackground()

public class eventupdate extends asynctask<string, void, string>   @override  protected void onpostexecute(string result) {         super.onpostexecute(result);          eventtext.settext("" + result); }   @override     protected string doinbackground(string... url) {    // work    return html;