Fragment not loaded in Android < 6.0 -


i replacing fragments this:

   @override    public void onnavigationdraweritemselected(int position) {         fragmentmanager = getsupportfragmentmanager();         android.support.v4.app.fragmenttransaction fragmenttransaction = fragmentmanager.begintransaction();         fragment newfragment = null;         string tag = "";         switch (position) {             case 0:                 newfragment = new myfragment();                 tag = "termine";                 break;             case 1:                 newfragment = new mymapfragment();                 tag = "map";                 break;             case 2:                 newfragment = new searchfragment();                 tag = "search";                 break;             case 3:                 break;             case 4:                 newfragment = new settingsfragment();                 tag = "settings";                 break;             case 5:                 newfragment = new aboutfragment();                 tag = "about";                 break;         }          if (newfragment != null) {             getsupportfragmentmanager().begintransaction()                     .replace(r.id.container, newfragment, tag)                     .addtobackstack(null)                     .commit();         }     } 

my gradle file:

buildscript {     repositories {         maven { url 'https://maven.fabric.io/public' }     }      dependencies {         classpath 'io.fabric.tools:gradle:1.+'     } } apply plugin: 'com.android.application' apply plugin: 'io.fabric'  repositories {     maven { url 'https://maven.fabric.io/public' } }  android {     compilesdkversion 23     buildtoolsversion '23.0.3' //    uselibrary 'org.apache.http.legacy'      defaultconfig {         applicationid "com.myapp.coolapp"         minsdkversion 16         targetsdkversion 23         multidexenabled true         vectordrawables.usesupportlibrary = true     }     buildtypes {         release {             minifyenabled false             proguardfiles getdefaultproguardfile('proguard-android.txt'), 'proguard-rules.txt'             zipalignenabled true             shrinkresources true         }     }     dexoptions {         javamaxheapsize "4g"     } }  dependencies {     compile filetree(dir: 'libs', include: ['*.jar'])     compile 'com.android.support:appcompat-v7:23.4.0'     compile 'com.android.support:support-v4:23.4.0'     compile 'com.android.support:multidex:1.0.1'     compile 'com.android.support:recyclerview-v7:23.4.0'     compile 'com.android.support:cardview-v7:23.4.0'     compile 'com.google.android.gms:play-services:8.4.0'     compile 'com.github.paolorotolo:appintro:3.4.0'     compile 'com.prolificinteractive:material-calendarview:1.3.0'     compile 'me.grantland:autofittextview:0.2.+'     compile 'com.squareup.picasso:picasso:2.5.2'     compile 'com.sothree.slidinguppanel:library:3.3.0'     compile 'com.plattysoft.leonids:leonidslib:1.3.1'     compile 'com.github.halysongoncalves:pugnotification:1.8.1'     compile 'com.squareup.okhttp3:okhttp:3.2.0'     compile 'com.github.amlcurran.showcaseview:library:5.4.3'     compile 'it.sephiroth.android.library.targettooltip:target-tooltip-library:+'     compile 'com.mikepenz:iconics-core:2.2.0@aar'     compile 'com.mikepenz:fontawesome-typeface:4.4.0.1@aar'     compile 'se.emilsjolander:stickylistheaders:2.7.0'     compile('com.crashlytics.sdk.android:crashlytics:2.5.6@aar') {         transitive = true;     }     compile('com.mikepenz:aboutlibraries:5.6.6@aar') {         transitive = true     }     compile('com.crashlytics.sdk.android:answers:1.3.7@aar') {         transitive = true;     } } 

activity_main.xml

<android.support.v4.widget.drawerlayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:app="http://schemas.android.com/apk/res-auto"     android:id="@+id/drawer"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:background="@color/myprimarycolor"     android:fitssystemwindows="true">      <linearlayout         android:layout_width="match_parent"         android:layout_height="match_parent"         android:orientation="vertical">          <android.support.v7.widget.toolbar             android:id="@+id/toolbar_actionbar"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:minheight="?attr/actionbarsize"             app:theme="@style/toolbarstyle" />          <framelayout             android:id="@+id/container"             android:layout_width="match_parent"             android:layout_height="match_parent"             android:clickable="true">          </framelayout>      </linearlayout>       <fragment         android:id="@+id/fragment_drawer"         android:name="com.myapp.coolapp.navigationdrawer.navigationdrawerfragment"         android:layout_width="@dimen/navigation_drawer_width"         android:layout_height="match_parent"         android:layout_gravity="start"         app:layout="@layout/fragment_navigation_drawer" />  </android.support.v4.widget.drawerlayout> 

navigationdrawerfragment.java

public class navigationdrawerfragment extends fragment implements navigationdrawercallbacks {      /**      * remember position of selected item.      */     private static final string state_selected_position = "selected_navigation_drawer_position";      /**      * per design guidelines, should show drawer on launch until user manually      * expands it. shared preference tracks this.      */     private static final string pref_user_learned_drawer = "navigation_drawer_learned";      /**      * pointer current callbacks instance (the activity).      */     private navigationdrawercallbacks mcallbacks;      /**      * helper component ties action bar navigation drawer.      */     public actionbardrawertoggle mactionbardrawertoggle;      private drawerlayout mdrawerlayout;     private recyclerview mdrawerlist;     private view mfragmentcontainerview;      private int mcurrentselectedposition = 0;     private boolean mfromsavedinstancestate;     private boolean muserlearneddrawer;      @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);          // read in flag indicating whether or not user has demonstrated awareness of         // drawer. see pref_user_learned_drawer details.         sharedpreferences sp = preferencemanager.getdefaultsharedpreferences(getactivity());         muserlearneddrawer = sp.getboolean(pref_user_learned_drawer, false);          if (savedinstancestate != null) {             mcurrentselectedposition = savedinstancestate.getint(state_selected_position);             mfromsavedinstancestate = true;         }     }      @override     public view oncreateview(layoutinflater inflater, viewgroup container,                              bundle savedinstancestate) {         view view = inflater.inflate(r.layout.fragment_navigation_drawer, container, false);         mdrawerlist = (recyclerview) view.findviewbyid(r.id.drawerlist);         linearlayoutmanager layoutmanager = new linearlayoutmanager(getactivity());         layoutmanager.setorientation(linearlayoutmanager.vertical);         mdrawerlist.setlayoutmanager(layoutmanager);         mdrawerlist.sethasfixedsize(true);          final list<navigationitem> navigationitems = getmenu();         navigationdraweradapter adapter = new navigationdraweradapter(navigationitems);         adapter.setnavigationdrawercallbacks(this);         mdrawerlist.setadapter(adapter);         selectitem(mcurrentselectedposition);         return view;     }      public boolean isdraweropen() {         return mdrawerlayout != null && mdrawerlayout.isdraweropen(mfragmentcontainerview);     }      public actionbardrawertoggle getactionbardrawertoggle() {         return mactionbardrawertoggle;     }      public drawerlayout getdrawerlayout() {         return mdrawerlayout;     }      @override     public void onnavigationdraweritemselected(int position) {         if (position != 3) {             selectitem(position);         }     }      public list<navigationitem> getmenu() {         list<navigationitem> items = new arraylist<navigationitem>();         items.add(new navigationitem(getresources().getstring(r.string.nav_title1)));         items.add(new navigationitem(getresources().getstring(r.string.nav_title2)));         items.add(new navigationitem(getresources().getstring(r.string.nav_title3)));         items.add(new navigationitem(""));         items.add(new navigationitem(getresources().getstring(r.string.nav_title4)));         items.add(new navigationitem(getresources().getstring(r.string.nav_title5)));         return items;     }      /**      * users of fragment must call method set navigation drawer interactions.      *      * @param fragmentid   android:id of fragment in activity's layout.      * @param drawerlayout drawerlayout containing fragment's ui.      * @param toolbar      toolbar of activity.      */     public void setup(int fragmentid, drawerlayout drawerlayout, toolbar toolbar) {         mfragmentcontainerview = getactivity().findviewbyid(fragmentid);         mdrawerlayout = drawerlayout;          mdrawerlayout.setstatusbarbackgroundcolor(getresources().getcolor(r.color.myprimarydarkcolor));          mactionbardrawertoggle = new actionbardrawertoggle(getactivity(), mdrawerlayout, toolbar, r.string.drawer_open, r.string.drawer_close) {             @override             public void ondrawerclosed(view drawerview) {                 super.ondrawerclosed(drawerview);                 if (!isadded()) return;                  getactivity().invalidateoptionsmenu();             }              @override             public void ondraweropened(view drawerview) {                 super.ondraweropened(drawerview);                 if (!isadded()) return;                 if (!muserlearneddrawer) {                     muserlearneddrawer = true;                     sharedpreferences sp = preferencemanager                             .getdefaultsharedpreferences(getactivity());                     sp.edit().putboolean(pref_user_learned_drawer, true).apply();                 }                 getactivity().invalidateoptionsmenu(); // calls onprepareoptionsmenu()             }         };         mdrawerlayout.post(new runnable() {             @override             public void run() {                 mactionbardrawertoggle.syncstate();             }         });         mdrawerlayout.setdrawerlistener(mactionbardrawertoggle);     }      private void selectitem(int position) {         mcurrentselectedposition = position;         if (mdrawerlayout != null) {             mdrawerlayout.closedrawer(mfragmentcontainerview);         }         if (mcallbacks != null) {             mcallbacks.onnavigationdraweritemselected(position);         }     }      public void opendrawer() {         mdrawerlayout.opendrawer(mfragmentcontainerview);     }      public void closedrawer() {         mdrawerlayout.closedrawer(mfragmentcontainerview);     }      @override     public void onattach(context context) {         super.onattach(context);         try {             mcallbacks = (navigationdrawercallbacks) context;         } catch (classcastexception e) {             throw new classcastexception("activity must implement navigationdrawercallbacks.");         }     }      @override     public void ondetach() {         super.ondetach();         mcallbacks = null;     }      @override     public void onsaveinstancestate(bundle outstate) {         super.onsaveinstancestate(outstate);         outstate.putint(state_selected_position, mcurrentselectedposition);     }      @override     public void onconfigurationchanged(configuration newconfig) {         super.onconfigurationchanged(newconfig);         // forward new configuration drawer toggle component.         mactionbardrawertoggle.onconfigurationchanged(newconfig);     }  } 

on devices android 6.0 works perfect, way should on devices < 6.0 app starts without problems content of fragment isn't replaced. fragments don't think fragment layout's problem.

what wrong configuration?