title: getActivity returning null from fragment
body: <p>For school I am making an android app. For this app I have a fragment, which shows a gridview with just strings, from a database. For this I need a fragment. When I call getActivity(), it returns null. The onAttach method, as suggested <a href="https://stackoverflow.com/questions/6215239/getactivity-returns-null-in-fragment-function">here</a> doesn't get called before the app crashes. How should I solve this?<br>
  weekFragmetn.xml:</p>
  
  <pre><code>package nl.siebeh.schoolmate;
  
  import java.util.ArrayList;
  
  import android.app.Activity;
  import android.content.Context;
  import android.os.Bundle;
  import android.support.v4.app.Fragment;
  import android.util.Log;
  import android.view.ContextMenu;
  import android.view.ContextMenu.ContextMenuInfo;
  import android.view.LayoutInflater;
  import android.view.MenuItem;
  import android.view.View;
  import android.view.ViewGroup;
  import android.widget.GridView;
  
  public class weekFragment extends Fragment {
      dbLayer db;
      Context mContext;
  
      @Override
      public void onAttach(Activity activity) {
          mContext = getActivity();
          Log.i("Schoolmate","onAttach called");
          super.onAttach(activity);
      }
  
      public weekFragment newInstance(String title) {
          Log.i("Schoolmate","newInstance called");
          db = new dbLayer(mContext);
          weekFragment fragment = new weekFragment();
          ArrayList&lt;ArrayList&lt;Object&gt;&gt; result = null;
  
          if(title == "leraren"){
              result = db.getAllRowsAsArrays("weekTeacher", null);
          }else if(title == "locatie"){
              result = db.getAllRowsAsArrays("weekLocation", null);
          }else if(title == "vakken"){
              result = db.getAllRowsAsArrays("weekSubjects", null);
          }
  
          String[] array = new String[60];
  
          for(int i = 0; i &lt; 60; i++){
              array[i] = "";
          }
  
          array[1] = getResources().getStringArray(R.array.days)[0];
          array[2] = getResources().getStringArray(R.array.days)[1];
          array[3] = getResources().getStringArray(R.array.days)[2];
          array[4] = getResources().getStringArray(R.array.days)[3];
          array[5] = getResources().getStringArray(R.array.days)[4];
  
          for(int i = 1; i &lt; 10; i++){
              array[i] = Integer.toString(i);
          }
  
          for(int position = 0; position &lt; result.size(); position++){
              ArrayList&lt;Object&gt; row = result.get(position);
              int hour = Integer.valueOf(row.get(1).toString()).intValue();
              int day =  Integer.valueOf(row.get(0).toString()).intValue();
              int pos = 6 * hour + day;
              array[pos] = row.get(position).toString();
          }
          fragment.mContent = array;
  
          return fragment;
      }
  
      private String[] mContent = {""};
  
      @Override
      public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
          if (container == null) {
              return null;
          }
          View v = inflater.inflate(R.layout.week_fragment, container, false);
          GridView gridview = (GridView) v.findViewById(R.id.gridview);
          gridview.setAdapter(new weekAdapter(mContext, mContent));
          return gridview;
      }
  
      @Override
      public boolean onContextItemSelected(MenuItem item) {
          return super.onContextItemSelected(item);
      }
  
      @Override
      public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {
          super.onCreateContextMenu(menu, v, menuInfo);
      }
  
  
  
  }
  </code></pre>
  
  <p>logcat: (since click on the item the item in a list that starts the activity, where the fragment is started/embedded)</p>
  
  <pre><code>    09-29 19:10:56.611: INFO/ActivityManager(70): Starting: Intent { cmp=nl.siebeh.schoolmate/.overviewWeek } from pid 536
  09-29 19:10:56.970: INFO/Schoolmate(536): newInstance called
  09-29 19:11:06.631: WARN/ActivityManager(70): Launch timeout has expired, giving up wake lock!
  09-29 19:11:06.671: WARN/ActivityManager(70): Activity idle timeout for HistoryRecord{40770188 nl.siebeh.schoolmate/.overviewWeek}
  09-29 19:12:20.661: DEBUG/SntpClient(70): request time failed: java.net.SocketException: Address family not supported by protocol
  09-29 19:14:11.811: DEBUG/dalvikvm(536): Debugger has detached; object registry had 413 entries
  09-29 19:14:11.811: ERROR/SchoolMate(536): java.lang.NullPointerException
  09-29 19:14:11.811: INFO/SchoolMate(536): Context is null
  09-29 19:14:11.820: WARN/System.err(536): java.lang.NullPointerException
  09-29 19:14:11.820: WARN/System.err(536):     at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:118)
  09-29 19:14:11.820: WARN/System.err(536):     at nl.siebeh.schoolmate.dbLayer.&lt;init&gt;(dbLayer.java:50)
  09-29 19:14:11.820: WARN/System.err(536):     at nl.siebeh.schoolmate.weekFragment.newInstance(weekFragment.java:31)
  09-29 19:14:11.820: WARN/System.err(536):     at nl.siebeh.schoolmate.fragmentAdapter.getItem(fragmentAdaptar.java:21)
  09-29 19:14:11.820: WARN/System.err(536):     at nl.siebeh.schoolmate.titleFragmentAdapter.getItem(titleFragmentAdapter.java:1)
  09-29 19:14:11.820: WARN/System.err(536):     at android.support.v4.app.FragmentPagerAdapter.instantiateItem(FragmentPagerAdapter.java:62)
  09-29 19:14:11.820: WARN/System.err(536):     at android.support.v4.view.ViewPager.addNewItem(ViewPager.java:321)
  09-29 19:14:11.820: WARN/System.err(536):     at android.support.v4.view.ViewPager.populate(ViewPager.java:441)
  09-29 19:14:11.820: WARN/System.err(536):     at android.support.v4.view.ViewPager.onAttachedToWindow(ViewPager.java:563)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.View.dispatchAttachedToWindow(View.java:6156)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1122)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.820: WARN/System.err(536):     at android.view.ViewRoot.performTraversals(ViewRoot.java:765)
  09-29 19:14:11.830: WARN/System.err(536):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1859)
  09-29 19:14:11.840: WARN/System.err(536):     at android.os.Handler.dispatchMessage(Handler.java:99)
  09-29 19:14:11.840: WARN/System.err(536):     at android.os.Looper.loop(Looper.java:123)
  09-29 19:14:11.840: WARN/System.err(536):     at android.app.ActivityThread.main(ActivityThread.java:3683)
  09-29 19:14:11.840: WARN/System.err(536):     at java.lang.reflect.Method.invokeNative(Native Method)
  09-29 19:14:11.840: WARN/System.err(536):     at java.lang.reflect.Method.invoke(Method.java:507)
  09-29 19:14:11.850: WARN/System.err(536):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
  09-29 19:14:11.850: WARN/System.err(536):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
  09-29 19:14:11.850: WARN/System.err(536):     at dalvik.system.NativeStart.main(Native Method)
  09-29 19:14:11.850: DEBUG/AndroidRuntime(536): Shutting down VM
  09-29 19:14:11.850: WARN/dalvikvm(536): threadid=1: thread exiting with uncaught exception (group=0x40015560)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536): FATAL EXCEPTION: main
  09-29 19:14:11.870: ERROR/AndroidRuntime(536): java.lang.NullPointerException
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at nl.siebeh.schoolmate.weekFragment.newInstance(weekFragment.java:49)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at nl.siebeh.schoolmate.fragmentAdapter.getItem(fragmentAdaptar.java:21)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at nl.siebeh.schoolmate.titleFragmentAdapter.getItem(titleFragmentAdapter.java:1)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.support.v4.app.FragmentPagerAdapter.instantiateItem(FragmentPagerAdapter.java:62)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.support.v4.view.ViewPager.addNewItem(ViewPager.java:321)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.support.v4.view.ViewPager.populate(ViewPager.java:441)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.support.v4.view.ViewPager.onAttachedToWindow(ViewPager.java:563)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.View.dispatchAttachedToWindow(View.java:6156)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1122)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewGroup.dispatchAttachedToWindow(ViewGroup.java:1127)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewRoot.performTraversals(ViewRoot.java:765)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1859)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.os.Handler.dispatchMessage(Handler.java:99)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.os.Looper.loop(Looper.java:123)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at android.app.ActivityThread.main(ActivityThread.java:3683)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at java.lang.reflect.Method.invokeNative(Native Method)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at java.lang.reflect.Method.invoke(Method.java:507)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
  09-29 19:14:11.870: ERROR/AndroidRuntime(536):     at dalvik.system.NativeStart.main(Native Method)
  09-29 19:14:11.890: WARN/ActivityManager(70):   Force finishing activity nl.siebeh.schoolmate/.overviewWeek
  09-29 19:14:12.413: WARN/ActivityManager(70): Activity pause timeout for HistoryRecord{40770188 nl.siebeh.schoolmate/.overviewWeek}
  09-29 19:14:21.910: WARN/ActivityManager(70): Launch timeout has expired, giving up wake lock!
  09-29 19:14:22.441: WARN/ActivityManager(70): Activity idle timeout for HistoryRecord{4070c7a0 nl.siebeh.schoolmate/.schoolmate}
  09-29 19:14:32.451: WARN/ActivityManager(70): Activity destroy timeout for HistoryRecord{40770188 nl.siebeh.schoolmate/.overviewWeek}
  </code></pre>