Why App ceashes when I try to check socket connection status?

Question

I am building a Remote PC control app. my code I want to start new activity only when socket connection is active or notify the user it is not active

class MyActivity extends Activity {
   static Boolean connect; 
   Socket client;
SendMessage send;
   //other codes
   bSend.setOnclickListener (new View.OnClikcListener () {
send=new SendMessage ();
send.execute ();
      if (connect==true){
         Intent I=new Intent (MyActivity.this, SubActivity.class);
         startActivity (I);
      } else {
         tStatus.setText ("Failed");
      }
   });
  }



class Send messages extends AsyncTask <  >{

protected void doInBackground (.....){
   client=new Socket("192.168.237.1", 6666);
   if(client.isConnected==true){
      connect=true;
       } else {
  connect=false;
    }
   }
}

but when I click button the app crashes Where is actual problem in code??

And here is my Log

12-08 21:13:47.930: E SensorManager(11323): thread start
12-08 21:13:47.935: D SensorManager(11323) registerListener :: handle = 0  name= LSM330DLC 3-axis Accelerometer delay= 200000 Listener= android.view.OrientationEventListener$SensorEventListenerImpl@41db1a58
12-08 21:13:47.945: D/SensorManager(11323): unregisterListener::  Listener= android.view.OrientationEventListener$SensorEventListenerImpl@41db1a58
12-08 21:13:47.945: D/Sensors(11323): Remain listener = Sending .. normal delay 200ms
12-08 21:13:47.945: I/Sensors(11323): sendDelay --- 200000000
12-08 21:13:47.945: D/SensorManager(11323): JNI - sendDelay
12-08 21:13:47.945: I/SensorManager(11323): Set normal delay = true
12-08 21:13:47.985: D/SensorManager(11323): registerListener :: handle = 0  name= LSM330DLC 3-axis Accelerometer delay= 200000 Listener= android.view.OrientationEventListener$SensorEventListenerImpl@41db1a58
12-08 21:13:48.030: D/libEGL(11323): loaded /system/lib/egl/libEGL_mali.so
12-08 21:13:48.040: D/libEGL(11323): loaded /system/lib/egl/libGLESv1_CM_mali.so
12-08 21:13:48.045: D/libEGL(11323): loaded /system/lib/egl/libGLESv2_mali.so
12-08 21:13:48.050: D/(11323): Device driver API match
12-08 21:13:48.050: D/(11323): Device driver API version: 10
12-08 21:13:48.050: D/(11323): User space API version: 10 
12-08 21:13:48.050: D/(11323): mali: REVISION=Linux-r2p4-02rel0 BUILD_DATE=Tue Oct 16 15:37:13 KST 2012 
12-08 21:13:48.090: D/OpenGLRenderer(11323): Enabling debug mode 0
12-08 21:13:50.020: D/AndroidRuntime(11323): Shutting down VM
12-08 21:13:50.020: W/dalvikvm(11323): threadid=1: thread exiting with uncaught exception (group=0x411302a0)
12-08 21:13:50.040: E/AndroidRuntime(11323): FATAL EXCEPTION: main
12-08 21:13:50.040: E/AndroidRuntime(11323): java.lang.NullPointerException
12-08 21:13:50.040: E/AndroidRuntime(11323):    at com.example.workarea.MainActivity$1.onClick(MainActivity.java:49)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.view.View.performClick(View.java:4211)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.view.View$PerformClick.run(View.java:17267)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.os.Handler.handleCallback(Handler.java:615)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.os.Handler.dispatchMessage(Handler.java:92)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.os.Looper.loop(Looper.java:137)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at android.app.ActivityThread.main(ActivityThread.java:4898)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at java.lang.reflect.Method.invokeNative(Native Method)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at java.lang.reflect.Method.invoke(Method.java:511)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
12-08 21:13:50.040: E/AndroidRuntime(11323):    at dalvik.system.NativeStart.main(Native Method)
12-08 21:14:07.425: I/Process(11323): Sending signal. PID: 11323 SIG: 9

Answer 1

if (connect==true){
     Intent I=new Intent (MyActivity.this, SubActivity.class);
     startActivity (I);
  } else {
     tStatus.setText ("Failed");
  }

you must add this code in onPostExecute method of the async task.