Android: "thread exiting with uncaught exception (group=0x4001d800)"

I'm doing a lan chat app bewteen android (client) and pc (java_server) both running on eclipse.The problem is android very untable and very often crash, however, its running very well on my java version of client and server. please help!

there is my code:

package android.client;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.PriorityQueue;
import java.util.Queue;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
 import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class Chat_client extends Activity implements Runnable {

private Socket socket = null;
//private Thread thread = null;
private DataOutputStream requestOut;
private int clientID;
private String playerName;
private DataInputStream requestIn;
private EditText text;
private ListView msgView;
private ArrayAdapter<String> msgArrayAdapter;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    try {
        socket = new Socket("192.168.2.2", 5558);
        Toast.makeText(this,
                "Connected to " + this.socket.getInetAddress(),
                Toast.LENGTH_LONG + 10).show();
        this.playerName = "wei";
        this.clientID = socket.getLocalPort();
        requestOut = new DataOutputStream(socket.getOutputStream());
        requestIn = new DataInputStream(socket.getInputStream());
        text = (EditText) findViewById(R.id.editText1);// black textfield
        msgArrayAdapter = new ArrayAdapter<String>(this, R.layout.message);
        msgView = (ListView) findViewById(R.id.in);
        msgView.setAdapter(this.msgArrayAdapter);
        new Thread(this).start();
    } catch (UnknownHostException uke) {
        Toast.makeText(this, "Host unknown:" + uke.getMessage(),
                Toast.LENGTH_LONG).show();
    } catch (IOException ioe) {
        Toast.makeText(this, "Unexpected exception: " + ioe.getMessage(),
                Toast.LENGTH_LONG).show();
    }
}


// This method is called at button click because we assigned the name to the
// "On Click property" of the button
public void myClickHandler(View v) {
    Toast.makeText(this, "sending", Toast.LENGTH_LONG/2).show();
    TextView view = (TextView) findViewById(R.id.editText1);
    String message = view.getText().toString();
    text.setText("");
    Packet p;
    if (message.startsWith("#")) {
        p = new Packet(playerName, 1, clientID,message.substring(1,    message.length()));
    } 
    else 
        p = new Packet(playerName, -1, clientID,message);
    try {
        this.requestOut.writeUTF(p.convertToSendFormat());
        requestOut.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    msgArrayAdapter.add("Me: <" + message + ">");

}

public void run() {
    while (true) {
        String r;
        try {
            r = this.requestIn.readUTF();
            if (r != null) {
                Packet p = convert(r);
                if (p != null)
                    handle(p);
            }
        } catch (IOException ioe) {
            System.exit(0);
        }
    }
}
private synchronized Packet convert(String n) {
    String data = "";
    String[] p = n.split(" ", 4);
    if (p.length < 4)
        return null;
    data = p[3];
    return new Packet(p[0], Integer.parseInt(p[1]), Integer.parseInt(p[2]),
            data);
}
public synchronized void handle(Packet re) {
    if (re.getChannelID() == clientID){
        msgArrayAdapter.add("Me" + re.toString());}
    else{
        msgArrayAdapter.add(re.getSenderName() + re.toString());
        }
    }

}

package android.client;

import java.io.Serializable;
/**
 * This class handles the networking packet
 * @author Wei
 */
public class Packet implements Serializable {
    private static final long serialVersionUID = 1509287973845358190L;
    private String senderName;
    private int actionID;
    private long channelID;
    private int sent;
    private String data;

    public Packet(String name, int actionID,int cid, String action2) {
        this.senderName=name;
        this.channelID = cid;
        this.actionID = actionID;
        this.data = action2;
        this.sent = -1;
    }

    public String getSenderName(){
        return this.senderName;
    }
    public int getActionID(){
      return this.actionID;
    }
    public String getData(){
        return this.data;
    }

    protected void setChannelID(int id){
        this.channelID = id;
    }
    public long getChannelID(){
        return this.channelID;
    }

    protected void setSent(boolean b){
        if(b)
        this.sent = 1;
        else
            this.sent=-1;
    }
    protected int checkSent(){
        return this.sent;
    }

    public String toString(){
        return (" : "+this.data);
    }
    public void addTimeStamp(String time){
        this.data+=time;
    }
    public String convertToSendFormat(){
        return this.senderName+" "+this.actionID+" "+this.channelID+" "+this.data;
    }
    public int getFlag() {
        return 0;
    }

    public void setFlag(boolean response) {
    }


}

there is the Log:

  10-12 12:54:22.763: DEBUG/AndroidRuntime(360): >>>>>>>>>>>>>> AndroidRuntime START <<<<<<<<<<<<<<
10-12 12:54:22.763: DEBUG/AndroidRuntime(360): CheckJNI is ON
10-12 12:54:22.895: DEBUG/AndroidRuntime(360): --- registering native functions ---
10-12 12:54:23.513: INFO/ActivityManager(59): Force stopping package android.client uid=10033
10-12 12:54:23.513: INFO/ActivityManager(59): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=android.client/.Chat_client }
10-12 12:54:23.633: DEBUG/AndroidRuntime(360): Shutting down VM
10-12 12:54:23.645: INFO/ActivityManager(59): Start proc android.client for activity android.client/.Chat_client: pid=366 uid=10033 gids={3003}
10-12 12:54:23.664: DEBUG/jdwp(360): Got wake-up signal, bailing out of select
10-12 12:54:23.664: DEBUG/dalvikvm(360): Debugger has detached; object registry had 1 entries
10-12 12:54:24.024: WARN/ActivityThread(366): Application android.client is waiting for the debugger on port 8100...
10-12 12:54:24.044: INFO/System.out(366): Sending WAIT chunk
10-12 12:54:24.054: INFO/dalvikvm(366): Debugger is active
10-12 12:54:24.244: INFO/System.out(366):开发者_如何学C Debugger has connected
10-12 12:54:24.244: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:24.444: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:24.644: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:24.843: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:25.053: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:25.254: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:25.454: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:25.654: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:25.866: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:26.075: INFO/System.out(366): waiting for debugger to settle...
10-12 12:54:26.284: INFO/System.out(366): debugger has settled (1322)
10-12 12:54:27.544: INFO/ActivityManager(59): Displayed activity android.client/.Chat_client: 3912 ms (total 3912 ms)
10-12 12:54:33.313: DEBUG/dalvikvm(124): GC_EXPLICIT freed 642 objects / 35976 bytes in 203ms
10-12 12:54:38.335: DEBUG/dalvikvm(225): GC_EXPLICIT freed 152 objects / 11144 bytes in 177ms
10-12 12:54:43.384: DEBUG/dalvikvm(261): GC_EXPLICIT freed 249 objects / 11840 bytes in 205ms
10-12 12:55:14.583: WARN/KeyCharacterMap(108): No keyboard for id 0
10-12 12:55:14.583: WARN/KeyCharacterMap(108): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
10-12 12:55:37.295: WARN/dalvikvm(366): threadid=7: thread exiting with uncaught exception (group=0x4001d800)

I have solved the prolbem by adding a handler method:

private Handler myHandler = new Handler(){
    @Override
    public void handleMessage(Message msg){
        String  str= (String) msg.obj;
        if(msg.what==1){
            msgArrayAdapter.add(str);
        }
    }
};`

and of course I have no idea why this works, but its just works.lol, thanks again for the help @Knickedi

Here would be the clean way to do this (I don't know whether this solves your actual problem). But updating the adapter array from another thread is not a good idea anyway. And if your device is rotating than you would create another thread instead using the already running one. And don't forget to refresh your list by calling msgArrayAdapter.notifyDataSetChanged() when you changed the array (the messages). Here's the blueprint and idea...

Your activity. It will react on configuration changes and the actual destroy the right way:

private MessagePollThread thread;

public void onCreate(Bundle b) {
    super.onCreate(b);

    thread = (MessagePollThread) getLastNonConfigurationInstance();

    if (thread == null) {
        // activity runs for first time - create thread
        thread = new MessagePollThread();
        thread.activity = this;
        thread.start();
    } else {
        // just update the thread with the new activity - it's started already
        thread.activity = this;
    }
}

public Object onRetainNonConfigurationInstance() {
    // retain the thread for configuration changes e.g. orientation change (see onCreate)
    return thread;

    // you could also retain your old received messages here
    // just return new Object [] {thread, messageArray} and handle that in onCreate
}

public void onDestroy() {
    super.onDestroy();

    if (isFinishing()) {
        // activity is about to destroy itself
        // shutdown the running thread
        thread.run = false;
        thread.interrupt(); // break the sleep
    }
}

The actual thread which handles requests (as inner static class of your activity):

private static class MessagePollThread extends Thread {

    public volatile boolean run = true;
    public volatile Chat_client activity;
    private Handler handler = new Handler();

    public void run() {

        // setup socket connection here

        while (run) {
            try {
                // you should / could also process send requests here
                // just use a synchronized list to check in your
                // activity (e.g. activity.messages) for new messages in queue
                // http://developer.android.com/reference/java/util/Collections.html#synchronizedList%28java.util.List%3CT%3E%29

                final String r = this.requestIn.readUTF();

                if (!run) {
                    // the thread could be shut down meanwhile
                    continue;
                }

                handler.post(new Runnable() {
                    public void run() {
                        activity.handleResult(r);
                    }
                }
            } catch (IOException e) {
                handler.post(new Runnable() {
                    public void run() {
                        activity.finish();
                    }
                }
            }

            try {
                // sleep for a while
                // non stop polling will drain your battery very fast
                sleep(1000);
            } catch (InterruptException e) {
                // do nothing, just proceed
            }
        }

        // destroy socket connection here
    }
}