NullPointerException

[sanjaykumarm]

I am using com.plattysoft.leonids:LeonidsLib:1.3.1 version of this library and getting the following crashes from google play store :

java.lang.NullPointerException
! 1 at com.plattysoft.leonids.ParticleSystem.onUpdate(ParticleSystem.java:556)
2 at com.plattysoft.leonids.ParticleSystem.access$100(ParticleSystem.java:35)
3 at com.plattysoft.leonids.ParticleSystem$1.run(ParticleSystem.java:363)
4 at java.util.Timer$TimerImpl.run(Timer.java:284)

So can you please check it and resolve it?

[plattysoft]

There is a lot of information missing here.
Is this a crash on the Demo app on Play Store? If so, on which example? And what are the steps to replicate. Is it 100% replicable?
I did re-check the examples right now and they seem to work fine.

If this is something you are getting on you own app, please post the code, you may be doing something wrong on the initialization of the Particle System.

[sanjaykumarm]

• Is this a crash on the Demo app on Play Store?
  Ans : It is on play store.
• It is not re-producible from my end but occasionally I am getting this error on google play store console and also getting this crash log on https://www.apteligent.com/

[plattysoft]

That was not my question. The question was if the crash was happening on the Demos, not if your app was on the Play Store.

Without steps to replicate, there's nothing I can do.

[raymondctc]

I have integrated the lib into my app and I have the same issue too. Not sure what's going on and here is the stacktrace from Crashlytics

Fatal Exception: java.lang.NullPointerException
       at com.plattysoft.leonids.ParticleSystem.onUpdate(ParticleSystem.java:556)
       at com.plattysoft.leonids.ParticleSystem.access$100(ParticleSystem.java:35)
       at com.plattysoft.leonids.ParticleSystem$2.onAnimationUpdate(ParticleSystem.java:445)
       at android.animation.ValueAnimator.animateValue(ValueAnimator.java:1251)
       at android.animation.ValueAnimator.animationFrame(ValueAnimator.java:1175)
       at android.animation.ValueAnimator.doAnimationFrame(ValueAnimator.java:1216)
       at android.animation.ValueAnimator$AnimationHandler.doAnimationFrame(ValueAnimator.java:637)
       at android.animation.ValueAnimator$AnimationHandler.run(ValueAnimator.java:660)
       at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
       at android.view.Choreographer.doCallbacks(Choreographer.java:574)
       at android.view.Choreographer.doFrame(Choreographer.java:543)
       at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
       at android.os.Handler.handleCallback(Handler.java:733)
       at android.os.Handler.dispatchMessage(Handler.java:95)
       at android.os.Looper.loop(Looper.java:136)
       at android.app.ActivityThread.main(ActivityThread.java:5372)
       at java.lang.reflect.Method.invokeNative(Method.java)
       at java.lang.reflect.Method.invoke(Method.java:515)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:970)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:786)
       at dalvik.system.NativeStart.main(NativeStart.java)

[raymondctc]

@smeet123 I probably figure out the reason for my case. I've been using a View.post() to force the animation to run on UI thread. I also have a destroy() call to .cancel() in ParticleSystem. It is very likely that the Runnable in my View.post() function executed after .cancel(), where mDrawingView will become null (check the code in onUpdate() and cancel()). See if that's your case too.

[sanjaykumarm]

@raymondctc Thank you so much for the solution, I will check it once I get time.

[smr99]

May not be the cause of the reported NPE, but I can see a data race in ParticleTimerTask.run():

    if(mPs.get() != null) {
        ParticleSystem ps = mPs.get();

The two lines should be inverted:

    ParticleSystem ps = mPs.get();
    if(ps != null) {

[renyuzhuo]

The same