Crash detected in onUpdate(long miliseconds) function

[PratikPsb99]

private void onUpdate(long miliseconds) { ............. mDrawingView.postInvalidate(); }

this mDrawingView.postInvalidate(); causing crash sometimes.

This issue is detected in firebase crashlytics. Here I am attaching the error also which is detected by firebase.

Fatal Exception: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.view.View.postInvalidate()' on a null object reference at com.plattysoft.leonids.ParticleSystem.onUpdate(:89) at com.plattysoft.leonids.ParticleSystem.access$100() at com.plattysoft.leonids.ParticleSystem$ParticleTimerTask.run(:20) at java.util.TimerThread.mainLoop(Timer.java:563) at java.util.TimerThread.run(Timer.java:513)