android - error: Only the original thread that created a view hierarchy can touch its views -

hi , thank looking @ question. intermediate programmer in c android newbie. have been trying chat programming working. assuming else in code below works perfectly. 1 question ask when try settext() thread running, exception above. looked @ many many websites , here too. found many things, not understand. please explain me in simple way or offer me simple fix if possible.

thank much!!

public class chatter extends activity {  private string name = "unknown user";  /** called when activity first created. */ @override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.main);        final edittext msgtoserver = (edittext) findviewbyid(r.id.msgbox);     final edittext chatfromserver = (edittext) findviewbyid(r.id.chatbox);       final button msgtoserver = (button) findviewbyid(r.id.sendbutton);      socket socket = null;     string ipaddress = "192.168.1.103";     try {         inetaddress serveraddr = inetaddress.getbyname(ipaddress);         socket socketmain = new socket(serveraddr, 4444);         socket = socketmain;     } catch (ioexception e) {         // todo auto-generated catch block         log.e("tcp", "error", e);     }      final outmsg outmsg = new outmsg(socket);     thread msgsenderthread = new thread(outmsg);     msgsenderthread.start();      //chatfromserver.post(new inmsg(socket, chatfromserver));     thread msgreceiverthread = new thread(new inmsg(socket, chatfromserver));     msgreceiverthread.start();      msgtoserver.setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view v) {             string msgtoserverstring;              msgtoserverstring = msgtoserver.gettext().tostring();             outmsg.message = name + ": " + msgtoserverstring;             outmsg.readytosend = true;             msgtoserver.settext("");         }     }); }  public void updateresultsinui (string msg) {     final edittext chatfromserver = (edittext) findviewbyid(r.id.chatbox);      chatfromserver.settext(msg);  }  public class inmsg implements runnable {      socket socket;     edittext chatfromserver;     public inmsg(socket socket, edittext chatfromserver)     {         this.socket = socket;         this.chatfromserver = chatfromserver;     }      public void run(){         try {         bufferedreader in = new bufferedreader(new inputstreamreader(socket.getinputstream()));         string str = "firstmessagefromserver";             while (true)             {                 if (str.equals("firstmessagefromserver"))                     str = in.readline();                 else                     str = str + "\n" + in.readline();                 log.e("tcp", "got message: " + str);      //here went wrong******************                 chatfromserver.settext(str);      //******************************************             }         } catch (ioexception e) {             // todo auto-generated catch block             log.e("tcp", "error in receiving", e);         }     }  }  @override public boolean oncreateoptionsmenu(menu menu) {     menuinflater inflater = getmenuinflater();     inflater.inflate(r.menu.menu, menu);     return true; }  @override public boolean onoptionsitemselected(menuitem item) {     // handle item selection     switch (item.getitemid()) {     case r.id.setnamemenu:         setname();         return true;     default:         return super.onoptionsitemselected(item);     } }  public void populatechatbox (string msgfroms) {     log.e("tcp", "going in popc");     final edittext textnameinput = (edittext) findviewbyid(r.id.namebox);     log.e("tcp", " popc");     textnameinput.settext(msgfroms);     log.e("tcp", "going out popc"); }  public void setname() {     setcontentview(r.layout.custom_dialog);     final edittext textnameinput = (edittext) findviewbyid(r.id.namebox);     button submitnamebutton = (button) findviewbyid(r.id.submitnamebutton);     submitnamebutton.setonclicklistener(new onclicklistener() {     @override         public void onclick(view v) {         string nameinput = textnameinput.gettext().tostring();             if (!name.equals(""))                 name = nameinput;             setcontentview(r.layout.main);         }     }); } } 

in run() method:

message msg = new message(); string texttochange = "text"; msg.obj = texttochange; mhandler.sendmessage(msg); 

create mhandler in ui thread;

handler mhandler = new handler() {         @override         public void handlemessage(message msg) {             string text = (string)msg.obj;             //call settext here         } };