android.support.v4.app.Fragment.mFragmentManager' on a null object reference -

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i have follow lines of code using create navigationview load fragments , android application. getting error: android.support.v4.app.fragment.mfragmentmanager' on null object reference. created fragments , navigationview works.

public void selectdraweritem(menuitem menuitem){      fragment fragment = null;     class fragmentclass = null;      switch(menuitem.getitemid()){         case r.id.nav_show_all_events_activity:             fragmentclass = alleventsfragment.class;             break;         case r.id.nav_whats_hot_today_activity:             fragmentclass = whatshotfragment.class;             break;     }      try {         fragment = (fragment) fragmentclass.newinstance();     } catch (exception e) {         e.printstacktrace();     }      fragmentmanager fragmentmanager = getsupportfragmentmanager();     fragmentmanager.begintransaction().replace(r.id.flcontent, fragment).commit();      menuitem.setchecked(true);     settitle(menuitem.gettitle());     mdrawer.closedrawers(); }

are sure have 2 menuitems in menu ? if there more, end null fragment. add 'default' case switch statement:

switch(menuitem.getitemid()){     case r.id.nav_show_all_events_activity:         fragmentclass = alleventsfragment.class;         break;     case r.id.nav_whats_hot_today_activity:         fragmentclass = whatshotfragment.class;         break;     default:         return; }

that should ensure fragment not null.


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