java - GridviewLayoutManager with headers -

i working on app

i have implemented working recycler view receives jsonarray, passes data string array.

i want add section headers layout manager.

i have read 2 schools of thought on this: - change spansize of view match total columns of grid - create custom adapter loads different view if item section header.

im not sure way go , starting confuse me

i have list of data in array includes both headers , grid data (mydataset), have created array mapping dataset in (mydatamap). in mydatamap have list of field types (1 header , 0 griddata. hoping pass both arrays adaptor , decide if header or griditem , load appropriate view.

i leaning more towards loading different view header items, allowing me customise layout of header easier.

here adaptor code

package com.example.alex.recyclerview2;  import java.util.arraylist; import android.content.context; import android.support.v7.widget.recyclerview; import android.view.layoutinflater; import android.view.view; import android.view.view.onclicklistener; import android.view.viewgroup; import android.widget.imageview; import android.widget.textview;  import com.squareup.picasso.picasso;  public class myadapter extends recyclerview.adapter<myadapter.viewholder> {     private arraylist<string> mdataset;     private arraylist<integer> mdatamap;      private context context;     // provide reference views each data item     // complex data items may need more 1 view per item, ,     // provide access views data item in view holder     public class viewholder extends recyclerview.viewholder {         // each data item string in case         public textview txtheader;         public textview txtfooter;         public imageview imgimage;          public viewholder(view v) {             super(v);             txtheader = (textview) v.findviewbyid(r.id.firstline);             txtfooter = (textview) v.findviewbyid(r.id.secondline);             imgimage = (imageview) v.findviewbyid(r.id.icon);         }     }      public void add(int position, string item) {         mdataset.add(position, item);         notifyiteminserted(position);     }      public void remove(string item) {         int position = mdataset.indexof(item);         mdataset.remove(position);         notifyitemremoved(position);     }      // provide suitable constructor (depends on kind of dataset)     public myadapter(arraylist<string> mydataset, arraylist<integer> mydatamap) {mdataset = mydataset;mydatamap=mdatamap; }      // create new views (invoked layout manager)     @override     public myadapter.viewholder oncreateviewholder(viewgroup parent,                                                    int viewtype) {         // create new view         view v = layoutinflater.from(parent.getcontext()).inflate(r.layout.sub_layout, parent, false);          context = v.getcontext();          // set view's size, margins, paddings , layout parameters         viewholder vh = new viewholder(v);         return vh;     }      // replace contents of view (invoked layout manager)     @override     public void onbindviewholder(viewholder holder, int position) {         // - element dataset @ position         // - replace contents of view element         final string name = mdataset.get(position);          picasso.with(context).load("http://www.500kgiveaway.co.uk/" + name).resize(200,200).into(holder.imgimage);  //        holder.txtheader.settext(mdataset.get(position));         holder.txtheader.settext(name);          holder.txtheader.setonclicklistener(new onclicklistener() {             @override             public void onclick(view v) {                 remove(name);             }         });          holder.txtfooter.settext("footer: " + mdataset.get(position));      }      // return size of dataset (invoked layout manager)     @override     public int getitemcount() {         return mdataset.size();     }  } 

ive not had interest in post here answer

i hope else

what have done implemented custom view adaptor manage item types

import android.content.context; import android.support.v7.widget.recyclerview; import android.view.layoutinflater; import android.view.view; import android.view.viewgroup; import android.widget.imageview; import android.widget.textview;  import com.squareup.picasso.picasso;  import java.util.arraylist;  public class elementsadapter extends recyclerview.adapter<elementsadapter.viewholder> {     private arraylist<string> mdataset;     private arraylist<integer> mdatamap;      public context context;      private static final int view_header = 0;     private static final int view_normal = 1;      private view headerview;     private int datasetsize;      public class viewholder extends recyclerview.viewholder {         // each data item string in case         public textview txtheader;         public textview txtfooter;         public imageview imgimage;           //header         public textview headertext;          public viewholder(view v, int viewtype) {             super(v);             switch (viewtype){                 case 1:                     txtheader = (textview) v.findviewbyid(r.id.firstline);                     txtfooter = (textview) v.findviewbyid(r.id.secondline);                     imgimage = (imageview) v.findviewbyid(r.id.icon);                case 0:                     headertext = (textview) v.findviewbyid(r.id.headertext);            }         }      }      public elementsadapter(arraylist<string> mydataset, arraylist<integer> mydatamap) {         mdataset = mydataset;         mdatamap = mydatamap;     }        @override     public int getitemviewtype(int position) {         return isheader(position) == 1 ? view_header : view_normal;     }      @override     public int getitemcount() {         return mdataset.size();     }      @override     public viewholder oncreateviewholder(viewgroup parent, int viewtype) {         if (viewtype == view_header) {             // create new view             view sub_view = layoutinflater.from(parent.getcontext()).inflate(r.layout.header, parent, false);              context context = sub_view.getcontext();              // set view's size, margins, paddings , layout parameters             viewholder vh = new viewholder(sub_view,viewtype);              return vh;   //            return new headerviewholder(headerview);          } else {             // create new view             view sub_view = layoutinflater.from(parent.getcontext()).inflate(r.layout.sub_layout, parent, false);              context = sub_view.getcontext();              // set view's size, margins, paddings , layout parameters             viewholder vh = new viewholder(sub_view, viewtype);              return vh;           }     }      @override     public void onbindviewholder(viewholder viewholder, int position) {         if (isheader(position) == 1) {              // - element dataset @ position             // - replace contents of view element             final string name = mdataset.get(position);  //        holder.txtheader.settext(mdataset.get(position));             viewholder.headertext.settext(name);          } else {      // - element dataset @ position     // - replace contents of view element     final string name = mdataset.get(position);      picasso.with(context).load("http://www.500kgiveaway.co.uk/"+name).resize(200,200).into(viewholder.imgimage);  //        holder.txtheader.settext(mdataset.get(position));     viewholder.txtheader.settext(name);      viewholder.txtheader.setonclicklistener(new view.onclicklistener()      {         @override         public void onclick (view v){         //remove(name);     }     }      );      viewholder.txtfooter.settext("footer: "+mdataset.get(position)); }          //viewholder holder = (viewholder) viewholder;         //holder.textview.settext("position " + (position - 1));     }      public int isheader(int position) {         return mdatamap.get(position) ==1 ? 1:0;} }