My application closes when i turn off my screen and turn it back on.
Logcat tells me that the cause of this error is pointing to java line 60 in my CourseFragment.class which extends Fragment.
mViewPager.setAdapter(infoTechPageAdapter);
I am implementing a ViewPager in my CourseFragment.class which extends Fragment.
Here's my code:
public class CourseFragment extends Fragment {
public static final String ARG_POSITION_NUMBER = "course_number";
private int position;
public CourseFragment() {
// Empty constructor required for fragment subclasses
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView;
position = getArguments().getInt("position");
String course = getResources().getStringArray(
R.array.array_navigation_drawer)[position];
getActivity().setTitle(course);
rootView = inflater.inflate(R.layout.activity_drawer_fragment,
container, false);
return rootView;
}// end onCreateView
@Override
public void onStart() {
super.onStart();
ViewPager mViewPager = (ViewPager) getActivity().findViewById(
R.id.pagerYear);
Log.i("posit", String.valueOf(position));
switch (position) {
case 0:
InfoTechPageAdapter infoTechPageAdapter = new InfoTechPageAdapter(
getActivity().getSupportFragmentManager());
mViewPager.setAdapter(infoTechPageAdapter);
break;
case 1:
ComSciPageAdapter comSciPageAdapter = new ComSciPageAdapter(
getActivity().getSupportFragmentManager());
mViewPager.setAdapter(comSciPageAdapter);
break;
case 2:
ProfilePageAdapter profilePageAdapter = new ProfilePageAdapter(
getActivity().getSupportFragmentManager());
mViewPager.setAdapter(profilePageAdapter);
break;
}
}// end onStart
}
Logcat
09-22 10:54:03.830: E/AndroidRuntime(2917): FATAL EXCEPTION: main
09-22 10:54:03.830: E/AndroidRuntime(2917): java.lang.IllegalStateException: Observer android.support.v4.view.ViewPager$PagerObserver@4239b3e8 was not registered.
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.database.Observable.unregisterObserver(Observable.java:69)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.view.PagerAdapter.unregisterDataSetObserver(PagerAdapter.java:294)
09-22 10:54:03.830: E/AndroidRuntime(2917): at com.usjr.sss.adapter.InfoTechPageAdapter.unregisterDataSetObserver(InfoTechPageAdapter.java:21)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.view.ViewPager.setAdapter(ViewPager.java:409)
09-22 10:54:03.830: E/AndroidRuntime(2917): at com.usjr.sss.fragment.CourseFragment.onStart(CourseFragment.java:60)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.Fragment.performStart(Fragment.java:1502)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:957)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1460)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:472)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.view.ViewPager.setAdapter(ViewPager.java:415)
09-22 10:54:03.830: E/AndroidRuntime(2917): at com.usjr.sss.fragment.CourseFragment.onStart(CourseFragment.java:60)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.Fragment.performStart(Fragment.java:1502)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:957)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1086)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentManagerImpl.dispatchStart(FragmentManager.java:1882)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:573)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1164)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.Activity.performStart(Activity.java:5114)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.Activity.performRestart(Activity.java:5169)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.ActivityThread.handleSleeping(ActivityThread.java:3408)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.ActivityThread.access$2700(ActivityThread.java:153)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1426)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.os.Handler.dispatchMessage(Handler.java:99)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.os.Looper.loop(Looper.java:137)
09-22 10:54:03.830: E/AndroidRuntime(2917): at android.app.ActivityThread.main(ActivityThread.java:5227)
09-22 10:54:03.830: E/AndroidRuntime(2917): at java.lang.reflect.Method.invokeNative(Native Method)
09-22 10:54:03.830: E/AndroidRuntime(2917): at java.lang.reflect.Method.invoke(Method.java:511)
09-22 10:54:03.830: E/AndroidRuntime(2917): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
09-22 10:54:03.830: E/AndroidRuntime(2917): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:562)
09-22 10:54:03.830: E/AndroidRuntime(2917): at dalvik.system.NativeStart.main(Native Method)