SharedPreferences: extends Activity crashes App

[simone giusti]

I would like to use SharedPrefs but when I extend the class App crashes.

package it.rockopera.SCSremote;

/**
 * Created by Simone on 04/12/2015.
 */

import android.content.Context;
import android.content.SharedPreferences;

import android.util.Log;
import java.io.*;
import java.net.InetAddress;
import java.net.Socket;
import android.app.Activity;
import android.os.Bundle;



public class TcpClient extends Activity{

    public String T_IP = "1";
  //  public int T_PORT = 2;



    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);


            SharedPreferences userDetails = this.getSharedPreferences("MyPrefs", Context.MODE_PRIVATE);
            T_IP = userDetails.getString("IPkey", "192.168.1.100");  // (key, default)
          //  T_PORT = Integer.parseInt(userDetails.getString("PORTkey", "23"));





    }



    public final String SERVER_IP = T_IP ; //computer IP address

    public final int SERVER_PORT = 20;
    // message to send to the server
    private String mServerMessage;
    // sends message received notifications
    private OnMessageReceived mMessageListener = null;
    // while this is true, the server will continue running
    private boolean mRun = false;
    // used to send messages
    private PrintWriter mBufferOut;
    // used to read messages from the server
    private BufferedReader mBufferIn;

    /**
     * Constructor of the class. OnMessagedReceived listens for the messages received from server
     */
    public TcpClient(OnMessageReceived listener) {
        mMessageListener = listener;
    }

    /**
     * Sends the message entered by client to the server
     *
     * @param message text entered by client
     */
    public void sendMessage(String message) {
        if (mBufferOut != null && !mBufferOut.checkError()) {
            mBufferOut.println(message);
            mBufferOut.flush();
        }
    }

    /**
     * Close the connection and release the members
     */
    public void stopClient() {

        // send mesage that we are closing the connection
        sendMessage(Constants.CLOSED_CONNECTION+"Kazy");

        mRun = false;

        if (mBufferOut != null) {
            mBufferOut.flush();
            mBufferOut.close();
        }

        mMessageListener = null;
        mBufferIn = null;
        mBufferOut = null;
        mServerMessage = null;
    }

    public void run() {

        mRun = true;

        try {
            //here you must put your computer's IP address.
            InetAddress serverAddr = InetAddress.getByName(SERVER_IP);

            Log.e("TCP Client", "C: Connecting..." + SERVER_IP);

            //create a socket to make the connection with the server
            Socket socket = new Socket(serverAddr, SERVER_PORT);

            try {

                //sends the message to the server
                mBufferOut = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())), true);

                //receives the message which the server sends back
                mBufferIn = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                // send login name
                sendMessage(Constants.LOGIN_NAME+"Kazy");

                //in this while the client listens for the messages sent by the server
                while (mRun) {

                    mServerMessage = mBufferIn.readLine();

                    if (mServerMessage != null && mMessageListener != null) {
                        //call the method messageReceived from MyActivity class
                        mMessageListener.messageReceived(mServerMessage);
                    }

                }

                Log.e("RESPONSE FROM SERVER", "S: Received Message: '" + mServerMessage + "'");

            } catch (Exception e) {

                Log.e("TCP", "S: Error", e);

            } finally {
                //the socket must be closed. It is not possible to reconnect to this socket
                // after it is closed, which means a new socket instance has to be created.
                socket.close();
            }

        } catch (Exception e) {

            Log.e("TCP", "C: Error", e);

        }

    }

    //Declare the interface. The method messageReceived(String message) will must be implemented in the MyActivity
    //class at on asynckTask doInBackground
    public interface OnMessageReceived {
        public void messageReceived(String message);
    }





}

this is logCat:

12-07 10:52:31.942 1287-4996/? I/ActivityManager: START u0 {act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10200000 cmp=it.rockopera.SCSremote/.SplashActivity (has extras)} from uid 10008 on display 0
12-07 10:52:32.238 1287-1736/? I/ActivityManager: Start proc 10104:it.rockopera.SCSremote/u0a59 for activity it.rockopera.SCSremote/.SplashActivity
12-07 10:52:32.255 10104-10104/? I/art: Not late-enabling -Xcheck:jni (already on)
12-07 10:52:32.256 10104-10104/? I/art: Late-enabling JIT
12-07 10:52:32.341 10104-10104/? I/art: JIT created with code_cache_capacity=2MB compile_threshold=1000
12-07 10:52:32.537 10104-10104/? W/System: ClassLoader referenced unknown path: /data/app/it.rockopera.SCSremote-1/lib/x86
12-07 10:52:33.322 10104-10115/? I/art: Background sticky concurrent mark sweep GC freed 12860(551KB) AllocSpace objects, 0(0B) LOS objects, 0% free, 5MB/5MB, paused 78.761ms total 437.276ms
12-07 10:52:33.656 941-1005/? E/SurfaceFlinger: ro.sf.lcd_density must be defined as a build property
12-07 10:52:33.661 10104-10118/? D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
12-07 10:52:33.775 10104-10115/? I/art: Background partial concurrent mark sweep GC freed 37(1776B) AllocSpace objects, 0(0B) LOS objects, 39% free, 5MB/9MB, paused 126.134ms total 379.222ms
12-07 10:52:33.903 10104-10118/? I/OpenGLRenderer: Initialized EGL, version 1.4
12-07 10:52:34.082 10104-10118/? W/EGL_emulation: eglSurfaceAttrib not implemented
12-07 10:52:34.082 10104-10118/? W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xad7a00a0, error=EGL_SUCCESS
12-07 10:52:34.535 2355-2385/? E/Surface: getSlotFromBufferLocked: unknown buffer: 0xab81b270
12-07 10:52:35.532 1287-1324/? I/ActivityManager: Displayed it.rockopera.SCSremote/.SplashActivity: +3s320ms (total +34s936ms)
12-07 10:52:38.452 1287-1734/? I/ActivityManager: START u0 {cmp=it.rockopera.SCSremote/.ClientActivity} from uid 10059 on display 0
12-07 10:52:38.678 10104-10118/? W/EGL_emulation: eglSurfaceAttrib not implemented
12-07 10:52:38.679 10104-10118/? W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xad7a5d00, error=EGL_SUCCESS
12-07 10:52:39.361 10104-10104/? I/Choreographer: Skipped 31 frames!  The application may be doing too much work on its main thread.
12-07 10:52:39.395 10104-10126/? E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
                                                   Process: it.rockopera.SCSremote, PID: 10104
                                                   java.lang.RuntimeException: An error occurred while executing doInBackground()
                                                       at android.os.AsyncTask$3.done(AsyncTask.java:309)
                                                       at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
                                                       at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
                                                       at java.util.concurrent.FutureTask.run(FutureTask.java:242)
                                                       at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
                                                       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
                                                       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
                                                       at java.lang.Thread.run(Thread.java:818)
                                                    Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
                                                       at android.os.Handler.<init>(Handler.java:200)
                                                       at android.os.Handler.<init>(Handler.java:114)
                                                       at android.app.Activity.<init>(Activity.java:754)
                                                       at it.rockopera.SCSremote.TcpClient.<init>(TcpClient.java:60)
                                                       at it.rockopera.SCSremote.ClientActivity$ConnectTask.doInBackground(ClientActivity.java:237)
                                                       at it.rockopera.SCSremote.ClientActivity$ConnectTask.doInBackground(ClientActivity.java:231)
                                                       at android.os.AsyncTask$2.call(AsyncTask.java:295)
                                                       at java.util.concurrent.FutureTask.run(FutureTask.java:237)
                                                       at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
                                                       at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
                                                       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
                                                       at java.lang.Thread.run(Thread.java:818)
12-07 10:52:39.442 1287-1749/? W/ActivityManager:   Force finishing activity it.rockopera.SCSremote/.ClientActivity
12-07 10:52:39.564 941-941/? E/EGL_emulation: tid 941: eglCreateSyncKHR(1243): error 0x3004 (EGL_BAD_ATTRIBUTE)
12-07 10:52:39.722 1287-1733/? W/art: Long monitor contention event with owner method=android.graphics.Bitmap com.android.server.wm.WindowManagerService.screenshotApplicationsInner(android.os.IBinder, int, int, int, boolean) from WindowManagerService.java:6223 waiters=0 for 178ms
12-07 10:52:39.765 10104-10118/? E/Surface: getSlotFromBufferLocked: unknown buffer: 0xab818720
12-07 10:52:39.787 10104-10104/? D/AndroidRuntime: Shutting down VM
12-07 10:52:39.788 10104-10104/? I/Process: Sending signal. PID: 10104 SIG: 9
12-07 10:52:39.798 1287-1287/? W/art: Long monitor contention event with owner method=void com.android.server.am.ActivityManagerService.crashApplication(com.android.server.am.ProcessRecord, android.app.ApplicationErrorReport$CrashInfo) from ActivityManagerService.java:12502 waiters=0 for 370ms
12-07 10:52:39.807 1287-1307/? W/art: Long monitor contention event with owner method=void com.android.server.am.ActivityManagerService.crashApplication(com.android.server.am.ProcessRecord, android.app.ApplicationErrorReport$CrashInfo) from ActivityManagerService.java:12502 waiters=2 for 295ms
12-07 10:52:40.161 1287-1845/? I/OpenGLRenderer: Initialized EGL, version 1.4
12-07 10:52:40.311 1287-1307/? W/ActivityManager: Activity pause timeout for ActivityRecord{9419f6 u0 it.rockopera.SCSremote/.ClientActivity t159 f}
12-07 10:52:40.312 1287-1845/? W/EGL_emulation: eglSurfaceAttrib not implemented
12-07 10:52:40.313 1287-1845/? W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x9b9fe060, error=EGL_SUCCESS
12-07 10:52:40.316 1287-1293/? I/art: Background partial concurrent mark sweep GC freed 10893(817KB) AllocSpace objects, 3(60KB) LOS objects, 33% free, 7MB/11MB, paused 18.552ms total 566.721ms
12-07 10:52:40.453 939-939/? E/lowmemorykiller: Error writing /proc/10104/oom_score_adj; errno=22
12-07 10:52:40.611 2355-2385/? W/EGL_emulation: eglSurfaceAttrib not implemented
12-07 10:52:40.611 2355-2385/? W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xa1562c60, error=EGL_SUCCESS
12-07 10:52:40.638 1287-1734/? D/GraphicsStats: Buffer count: 4
12-07 10:52:40.647 1287-1341/? W/InputDispatcher: channel '41c4e15 it.rockopera.SCSremote/it.rockopera.SCSremote.SplashActivity (server)' ~ Consumer closed input channel or an error occurred.  events=0x9
12-07 10:52:40.647 1287-1341/? E/InputDispatcher: channel '41c4e15 it.rockopera.SCSremote/it.rockopera.SCSremote.SplashActivity (server)' ~ Channel is unrecoverably broken and will be disposed!
12-07 10:52:40.652 1287-1341/? W/InputDispatcher: channel '8dfdf82 it.rockopera.SCSremote/it.rockopera.SCSremote.ClientActivity (server)' ~ Consumer closed input channel or an error occurred.  events=0x9
12-07 10:52:40.653 1287-1341/? E/InputDispatcher: channel '8dfdf82 it.rockopera.SCSremote/it.rockopera.SCSremote.ClientActivity (server)' ~ Channel is unrecoverably broken and will be disposed!
12-07 10:52:40.675 1287-1642/? I/ActivityManager: Process it.rockopera.SCSremote (pid 10104) has died
12-07 10:52:40.751 1287-1734/? I/WindowState: WIN DEATH: Window{41c4e15 u0 it.rockopera.SCSremote/it.rockopera.SCSremote.SplashActivity}
12-07 10:52:40.752 1287-1734/? W/InputDispatcher: Attempted to unregister already unregistered input channel '41c4e15 it.rockopera.SCSremote/it.rockopera.SCSremote.SplashActivity (server)'
12-07 10:52:40.766 1287-4996/? W/art: Long monitor contention event with owner method=void com.android.server.wm.WindowAnimator$1.doFrame(long) from WindowAnimator.java:121 waiters=2 for 127ms
12-07 10:52:40.769 1287-4996/? I/WindowState: WIN DEATH: Window{8dfdf82 u0 it.rockopera.SCSremote/it.rockopera.SCSremote.ClientActivity}
12-07 10:52:40.769 1287-4996/? W/InputDispatcher: Attempted to unregister already unregistered input channel '8dfdf82 it.rockopera.SCSremote/it.rockopera.SCSremote.ClientActivity (server)'
12-07 10:52:40.808 1287-1642/? W/art: Long monitor contention event with owner method=void com.android.server.wm.WindowAnimator$1.doFrame(long) from WindowAnimator.java:121 waiters=3 for 111ms
12-07 10:52:40.823 1287-1749/? W/art: Long monitor contention event with owner method=void com.android.server.am.ActivityManagerService$AppDeathRecipient.binderDied() from ActivityManagerService.java:1305 waiters=0 for 136ms
12-07 10:52:41.005 1287-1308/? I/Choreographer: Skipped 36 frames!  The application may be doing too much work on its main thread.
12-07 10:52:41.055 1287-1845/? E/Surface: getSlotFromBufferLocked: unknown buffer: 0xa15fc870
12-07 10:52:41.237 1287-4996/? W/InputMethodManagerService: Got RemoteException sending setActive(false) notification to pid 10104 uid 10059
12-07 10:52:41.416 1287-1324/? W/AppOps: Finishing op nesting under-run: uid 1000 pkg android code 24 time=0 duration=0 nesting=0
12-07 10:52:41.609 1287-1324/? W/WindowAnimator: Failed to dispatch window animation state change.
                                                 android.os.DeadObjectException
                                                     at android.os.BinderProxy.transactNative(Native Method)
                                                     at android.os.BinderProxy.transact(Binder.java:503)
                                                     at android.view.IWindow$Stub$Proxy.onAnimationStopped(IWindow.java:534)
                                                     at com.android.server.wm.WindowAnimator.updateWindowsLocked(WindowAnimator.java:286)
                                                     at com.android.server.wm.WindowAnimator.animateLocked(WindowAnimator.java:678)
                                                     at com.android.server.wm.WindowAnimator.-wrap0(WindowAnimator.java)
                                                     at com.android.server.wm.WindowAnimator$1.doFrame(WindowAnimator.java:123)
                                                     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:856)
                                                     at android.view.Choreographer.doCallbacks(Choreographer.java:670)
                                                     at android.view.Choreographer.doFrame(Choreographer.java:603)
                                                     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
                                                     at android.os.Handler.handleCallback(Handler.java:739)
                                                     at android.os.Handler.dispatchMessage(Handler.java:95)
                                                     at android.os.Looper.loop(Looper.java:148)
                                                     at android.os.HandlerThread.run(HandlerThread.java:61)
                                                     at com.android.server.ServiceThread.run(ServiceThread.java:46)

[Swastik Dey]

Your exception is raised from a different class ClientActivity method doInBackground

Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:200)
at android.os.Handler.<init>(Handler.java:114)
at android.app.Activity.<init>(Activity.java:754)
at it.rockopera.SCSremote.TcpClient.<init>(TcpClient.java:60)
at it.rockopera.SCSremote.ClientActivity$ConnectTask.doInBackground(ClientActivity.java:237)
at it.rockopera.SCSremote.ClientActivity$ConnectTask.doInBackground(ClientActivity.java:231)

[simone giusti]

thanks .. but ...
how can I solve it ??
do have I to extend "ClientActivity"? it crashes !!
without extending I can't have sharedpreferences available !

thanks ...

[Swastik Dey]

Show us code of ClientActivity class.

[simone giusti]

package it.rockopera.SCSremote;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.app.AlertDialog;
import android.content.Intent;
import android.widget.Toast;


import java.util.ArrayList;

public class ClientActivity extends Activity {

    private ListView mList;
    private ArrayList<String> arrayList;
    private ClientListAdapter mAdapter;
    private TcpClient mTcpClient;

    /** Called when the user clicks the SETTINGS in menu
    public void CallSettingsfromMenu(View view) {
        // Do something in response to button
     }  */



     /**   startActivity(new Intent(ClientActivity.this, settings.class));*/


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        arrayList = new ArrayList<String>();

        //final EditText editText = (EditText) findViewById(R.id.editText);
        Button GO = (Button) findViewById(R.id.GO_button);
        Button ESC = (Button) findViewById(R.id.ESC_button);
        Button RW = (Button) findViewById(R.id.RW_button);
        Button FF = (Button) findViewById(R.id.FF_button);



        //relate the listView from java to the one created in xml
        mList = (ListView) findViewById(R.id.list);
        mAdapter = new ClientListAdapter(this, arrayList);
        mList.setAdapter(mAdapter);

        GO.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                String message = "scsGO(\"0\")";


                //add the text in the arrayList
                arrayList.add("c: " + message);

                //sends the message to the server
                if (mTcpClient != null) {
                    mTcpClient.sendMessage(message);
                }

                //refresh the list
                mAdapter.notifyDataSetChanged();
                //editText.setText("");
            }
        });



        ESC.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                String message = "scsStopAll";


                //add the text in the arrayList
                arrayList.add("c: " + message);

                //sends the message to the server
                if (mTcpClient != null) {
                    mTcpClient.sendMessage(message);
                }

                //refresh the list
                mAdapter.notifyDataSetChanged();
                //editText.setText("");
            }
        });





        RW.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                String message = "scsGoBack";


                //add the text in the arrayList
                arrayList.add("c: " + message);

                //sends the message to the server
                if (mTcpClient != null) {
                    mTcpClient.sendMessage(message);
                }

                //refresh the list
                mAdapter.notifyDataSetChanged();
                //editText.setText("");
            }
        });


        FF.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                String message = "scsGoToNext";


                //add the text in the arrayList
                arrayList.add("c: " + message);

                //sends the message to the server
                if (mTcpClient != null) {
                    mTcpClient.sendMessage(message);
                }

                //refresh the list
                mAdapter.notifyDataSetChanged();
                //editText.setText("");
            }
        });




    }




    @Override
    protected void onPause() {
        super.onPause();

        // disconnect
        mTcpClient.stopClient();
        mTcpClient = null;

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.main_menu, menu);
        return true;
    }

    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {

        if (mTcpClient != null) {
            // if the client is connected, enable the connect button and disable the disconnect one
            menu.getItem(1).setEnabled(true);
            menu.getItem(0).setEnabled(false);
        } else {
            // if the client is disconnected, enable the disconnect button and disable the connect one
            menu.getItem(1).setEnabled(false);
            menu.getItem(0).setEnabled(true);
            new ConnectTask().execute("");

            return true;
        }

        return super.onPrepareOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle item selection
        switch (item.getItemId()) {
            case R.id.connect:
                // connect to the server
                new ConnectTask().execute("");
                return true;
            case R.id.disconnect:
                // disconnect
                mTcpClient.stopClient();
                mTcpClient = null;
                // clear the data set
                arrayList.clear();
                // notify the adapter that the data set has changed.
                mAdapter.notifyDataSetChanged();
                return true;


            case R.id.settings:
                // open preferences





                startActivity(new Intent(ClientActivity.this, preferences.class));



                return true;


            default:
                return super.onOptionsItemSelected(item);
        }

    }

    public class ConnectTask extends AsyncTask<String, String, TcpClient> {

        @Override
        protected TcpClient doInBackground(String... message) {

            //we create a TCPClient object and
            mTcpClient = new TcpClient(new TcpClient.OnMessageReceived() {
                @Override
                //here the messageReceived method is implemented
                public void messageReceived(String message) {
                    //this method calls the onProgressUpdate
                    publishProgress(message);
                }
            });
            mTcpClient.run();

            return null;
        }

        @Override
        protected void onProgressUpdate(String... values) {
            super.onProgressUpdate(values);

            //in the arrayList we add the messaged received from server
            arrayList.add(values[0]);
            // notify the adapter that the data set has changed. This means that new message received
            // from server was added to the list
            mAdapter.notifyDataSetChanged();
        }
    }
}

[Swastik Dey]

Change the doinbackground method like this and see if you get any difference

@Override
        protected TcpClient doInBackground(String... message) {
 
            //we create a TCPClient object and
			
			
			ClientActivity.this.runOnUiThread(new Runnable(){

				@Override
				public void run() {
					// TODO Auto-generated method stub
					mTcpClient = new TcpClient(new TcpClient.OnMessageReceived() {
					@Override
                //here the messageReceived method is implemented
					public void messageReceived(String message) {
                    //this method calls the onProgressUpdate
						publishProgress(message);
					}
				});
					mTcpClient.run();
				}
				
			});
			
			
            
 
            return null;
        }

[simone giusti]

Thanks for your help.
With this code it stops crashing but the app does not work anymore.

The app was build for connecting to telnet server and sending some commands. It stopped connecting.

Can you help me ??