<FrameLayout
          android:id="@+id/content_frame"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
          >

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:background="@color/viewBg"
     app:layout_behavior="@string/appbar_scrolling_view_behavior"
     tools:context="com.ss.bhagwanchalisa.MainActivity"
     tools:showIn="@layout/activity_main">

     <android.support.v7.widget.RecyclerView
         android:id="@+id/recycler_view"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:clipToPadding="false"
         android:scrollbars="vertical" />

 </RelativeLayout>
 </FrameLayout>
 </RelativeLayout>

public class FirstFragment extends Fragment {
  View view;
  @Nullable
  @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    view=inflater.inflate(R.layout.firstlayout,container,false);
    return view;

}
}

public boolean onNavigationItemSelected(MenuItem item) {

    // Handle navigation view item clicks here.
    int id = item.getItemId();
    android.app.FragmentManager fragmentManager=getFragmentManager();
   Fragment f= new FirstFragment();
   FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
    if (id == R.id.nav_camera) {

        fragmentTransaction.replace(R.id.content_frame, f);

        fragmentTransaction.commit();

      Snackbar s=Snackbar.make(c ,"Hey",Snackbar.LENGTH_SHORT);
        s.show();
    } else if (id == R.id.nav_gallery) {
        fragmentManager.beginTransaction().replace(R.id.content_frame,new SecondFragment()).commit();

    } else if (id == R.id.nav_slideshow) {
        fragmentManager.beginTransaction().replace(R.id.content_frame,new ThirdFragment()).commit();
    } else if (id == R.id.nav_share) {

    } else if (id == R.id.nav_send) {

    }

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    drawer.closeDrawer(GravityCompat.START);
    return true;
}

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="First"
    android:id="@+id/textView2"
    android:layout_gravity="center_horizontal"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="198dp" />
<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/b1"
    android:text="Click" />

 </RelativeLayout>