java.lang.RuntimeException: Unable to destroy activity

09-22 11:48:21.953 12955-12955/com.moreunion.zhenghao E/AndroidRuntime: FATAL EXCEPTION: main

Process: com.moreunion.zhenghao, PID: 12955

java.lang.RuntimeException: Unable to destroy activity {com.moreunion.zhenghao/com.moreunion.zhenghao.ui.register.setpwd.SetPassword}: java.lang.NullPointerException: Attempt to invoke
interface method 'boolean rx.Subscription.isUnsubscribed()' on a null object reference

at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:4398)

at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:4417)

at android.app.ActivityThread.-wrap6(ActivityThread.java)

at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1629)

at android.os.Handler.dispatchMessage(Handler.java:102)

at android.os.Looper.loop(Looper.java:156)

at android.app.ActivityThread.main(ActivityThread.java:6524)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)

Caused by: java.lang.NullPointerException: Attempt to invoke interface method 'boolean rx.Subscription.isUnsubscribed()' on a null object reference

at com.moreunion.zhenghao.ui.register.setpwd.SetPasswordPresenter.closeSubScription(SetPasswordPresenter.java:40)

at com.moreunion.zhenghao.ui.register.setpwd.SetPassword.onDestroy(SetPassword.java:110)

at android.app.Activity.performDestroy(Activity.java:7136)

at android.app.Instrumentation.callActivityOnDestroy(Instrumentation.java:1158)

at android.app.ActivityThread.performDestroyActivity(ActivityThread.java:4385)

at android.app.ActivityThread.handleDestroyActivity(ActivityThread.java:4417)

at android.app.ActivityThread.-wrap6(ActivityThread.java)

at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1629)

at android.os.Handler.dispatchMessage(Handler.java:102)

at android.os.Looper.loop(Looper.java:156)

at android.app.ActivityThread.main(ActivityThread.java:6524)

at java.lang.reflect.Method.invoke(Native Method)

at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)

at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)