android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@8523de6 is not valid; is your activity running?
	at android.view.ViewRootImpl.setView(ViewRootImpl.java:1023)
	at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:408)
	at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:96)
	at android.app.Dialog.show(Dialog.java:346)
	at com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity.showProgressDialog(FaceRecognitionActivity.java:547)
	at com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity.saveTrainImagesIntoDB(FaceRecognitionActivity.java:249)
	at com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity.access$100(FaceRecognitionActivity.java:92)
	at com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity$3.onPostExecute(FaceRecognitionActivity.java:582)
	at com.entitcs.office_attendance.FaceRecognitionRelated.object.FaceRecognitionActivity$3.onPostExecute(FaceRecognitionActivity.java:562)
	at android.os.AsyncTask.finish(AsyncTask.java:755)
	at android.os.AsyncTask.access$900(AsyncTask.java:192)
	at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:772)
	at android.os.Handler.dispatchMessage(Handler.java:107)
	at android.os.Looper.loop(Looper.java:238)
	at android.app.ActivityThread.main(ActivityThread.java:7824)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:981)