Please find a solution to this problem

[saeedalaloul]

idRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.alansar.center, PID: 4513
java.lang.NullPointerException: Attempt to invoke interface method 'com.stepstone.stepper.Step com.stepstone.stepper.adapter.StepAdapter.findStep(int)' on a null object reference
at com.stepstone.stepper.StepperLayout.findCurrentStep(StepperLayout.java:937)
at com.stepstone.stepper.StepperLayout.onNext(StepperLayout.java:946)
at com.stepstone.stepper.StepperLayout.access$700(StepperLayout.java:70)
at com.stepstone.stepper.StepperLayout$OnNextClickListener.onClick(StepperLayout.java:185)
at android.view.View.performClick(View.java:4780)