setViewPager is throwing NullPointerException

[rodly]

mTabsAdapter = new TabsAdapter(getActivity().getSupportFragmentManager());
mViewPager = (ViewPager) view.findViewById(R.id.pager);
mViewPager.setAdapter(mTabsAdapter);

mPagerSlidingTabStrip = (PagerSlidingTabStrip) view.findViewById(R.id.tabs);
mPagerSlidingTabStrip.setViewPager(mViewPager); <-- fails here

<com.astuetz.PagerSlidingTabStrip
    android:id="@+id/tabs"
    android:layout_width="match_parent"
    android:layout_height="48dip" />

  <android.support.v4.view.ViewPager
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="0px"
    android:layout_weight="1">
  </android.support.v4.view.ViewPager>

Any reason that might be happening? Debugging shows that the ViewPager and PagerSlidingTabStrip are getting properly instantiated. The stack trace shows that it's occurring in the notifyDataSetChanged method.

java.lang.NullPointerException
            at com.astuetz.PagerSlidingTabStrip.notifyDataSetChanged(PagerSlidingTabStrip.java:200)
            at com.astuetz.PagerSlidingTabStrip.setViewPager(PagerSlidingTabStrip.java:182)
            at com.farmlogs.app.activities.MapFragment.onCreateView(MapFragment.java:64)
            at android.support.v4.app.Fragment.performCreateView(Fragment.java:1500)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:938)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1115)
            at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
            at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1478)
            at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:446)
            at android.os.Handler.handleCallback(Handler.java:733)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5001)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
            at dalvik.system.NativeStart.main(Native Method)

[armandsar]

You should override your adapters getPageTitle method because it is returning null

[RemiNV]

The documentation for getPageTitle states "This method may return null indicating no title for this page. The default implementation returns null.", so returning null from getPageTitle() is a valid usage, and this is a bug in the library. Default (or empty) page titles could be used to avoid this.