java.lang.NullPointerException: Attempt to invoke virtual method 'android.os.IBinder android.view.View.getWindowToken()' on a null object reference
	at com.entitcs.office_attendance.activities.MainActivity$10.onClick(MainActivity.java:391)
	at android.view.View.performClick(View.java:7503)
	at android.view.View.performClickInternal(View.java:7480)
	at android.view.View.access$3600(View.java:813)
	at android.view.View$PerformClick.run(View.java:28445)
	at android.os.Handler.handleCallback(Handler.java:938)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loop(Looper.java:223)
	at android.app.ActivityThread.main(ActivityThread.java:7948)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:603)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)