Sample app crashes on Android N

[drommk]

Hi @yongjhih, faced that issue while testing your sample app :

Steps to reproduce :

• log out of your fb app
• run the retrofacebook sample app
• login with your account
• accept FB-required permissions

=> crash

09-21 14:51:19.196 25885-25885/retrofacebook.app E/AndroidRuntime: FATAL EXCEPTION: main
                                                                   Process: retrofacebook.app, PID: 25885
                                                                   java.lang.NullPointerException: Attempt to invoke virtual method 'rx.Observable rx.Observable.observeOn(rx.Scheduler)' on a null object reference
                                                                       at rx.android.app.AppObservable.bindFragment(AppObservable.java:98)
                                                                       at retrofacebook.app.RxCardsFragment.load(RxCardsFragment.java:109)
                                                                       at retrofacebook.app.RxCardsFragment.setUserVisibleHint(RxCardsFragment.java:102)
                                                                       at android.support.v4.app.FragmentPagerAdapter.setPrimaryItem(FragmentPagerAdapter.java:130)
                                                                       at android.support.v4.view.ViewPager.populate(ViewPager.java:1104)
                                                                       at android.support.v4.view.ViewPager.populate(ViewPager.java:952)
                                                                       at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1474)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:610)
                                                                       at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:677)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:940)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
                                                                       at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:135)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
                                                                       at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
                                                                       at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
                                                                       at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
                                                                       at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6120)
                                                                       at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
                                                                       at com.android.internal.policy.DecorView.onMeasure(DecorView.java:687)
                                                                       at android.view.View.measure(View.java:19730)
                                                                       at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2271)
                                                                       at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1358)
                                                                       at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1607)
                                                                       at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1246)
                                                                       at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6301)
                                                                       at android.view.Choreographer$CallbackRecord.run(Choreographer.java:871)
                                                                       at android.view.Choreographer.doCallbacks(Choreographer.java:683)
                                                                       at android.view.Choreographer.doFrame(Choreographer.java:619)
                                                                       at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:857)
                                                                       at android.os.Handler.handleCallback(Handler.java:751)
                                                                       at android.os.Handler.dispatchMessage(Handler.java:95)
                                                                       at android.os.Looper.loop(Looper.java:154)
                                                                       at android.app.ActivityThread.main(ActivityThread.java:6077)
                                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
                                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
09-21 14:51:19.198 4751-5157/? W/ActivityManager:   Force finishing activity retrofacebook.app/.MainActivity
09-21 14:51:19.284 4751-6312/? I/OpenGLRenderer: Initialized EGL, version 1.4
09-21 14:51:19.284 4751-6312/? D/OpenGLRenderer: Swap behavior 1
09-21 14:51:19.363 26221-26298/? W/VideoCapabilities: Unrecognized profile 2130706433 for video/avc
09-21 14:51:19.394 4751-4800/? I/WindowManager: Destroying surface Surface(name=Starting retrofacebook.app) called by com.android.server.wm.WindowStateAnimator.destroySurface:2014 com.android.server.wm.WindowStateAnimator.destroySurfaceLocked:881 com.android.server.wm.WindowState.removeLocked:1449 com.android.server.wm.WindowManagerService.removeWindowInnerLocked:2478 com.android.server.wm.AppWindowToken.destroySurfaces:365 com.android.server.wm.WindowStateAnimator.finishExit:565 com.android.server.wm.AppWindowAnimator.stepAnimationLocked:427 com.android.server.wm.WindowAnimator.updateAppWindowsLocked:176 

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