android listview asynctask for textview and imageview -

i trying generate android listview google books api call, google books api call return json data 1 of these properties url book thumbnail thought running first asynctask call json google books api , onpostexecute run second asynctask fetch thumbnails , set them imageview behavior not correct , thumbnails not associated correct row in listview while fetching thumbnails imageview in first row being updated , when download completes order messed up.

below extract code:

private class booksearchlistadapter extends baseadapter {     private arraylist<book> mbooks = new arraylist<>();     private layoutinflater mlayoutinflater;      public booksearchlistadapter(context c, arraylist<book> books) {         mlayoutinflater = layoutinflater.from(c);         this.mbooks = books;     }      @override     public view getview(int position, view convertview, viewgroup parent) {         viewholder holder;         if (convertview == null) {             convertview = mlayoutinflater.inflate(r.layout.view_book_search_row, null);             holder = new viewholder();             holder.mimageview = (imageview) convertview.findviewbyid(r.id.book_cover_thumbnail);             holder.mtitletextview = (textview) convertview.findviewbyid(r.id.book_title);             holder.mauthortextview = (textview) convertview.findviewbyid(r.id.book_author);             convertview.settag(holder);         } else {             holder = (viewholder) convertview.gettag();         }         book b = mbooks.get(position);         holder.mauthortextview.settext(textutils.join(", ", b.getauthors()));         holder.mtitletextview.settext(b.gettitle());         if (!b.getthumbnail().equalsignorecase("")) {             new thumbnaildownloadertask(holder.mimageview).execute(b.getthumbnail());         }          return convertview;     }      @override     public int getcount() {         return mbooks.size();     }      @override     public object getitem(int position) {         return mbooks.get(position);     }      @override     public long getitemid(int position) {         return position;     } }  private static class viewholder {     imageview mimageview;     textview mtitletextview;     textview mauthortextview; }  private class searchbooktask extends asynctask<string, void, string> {      private final string tag = "searchbooktask";      private arraylist<book> mbooks = new arraylist<>();      private final static string book_items_key = "items";     private final static string book_volumeinfo_key = "volumeinfo";     private final static string book_imagelinks_key = "imagelinks";     private final static string book_id_key = "id";     private final static string book_title_key = "title";     private final static string book_authors_key = "authors";     private final static string book_description_key = "description";     private final static string book_thumbnail_key = "thumbnail";      @override     protected string doinbackground(string... params) {         string bookquery = params[0];         string url = uri.parse(endpoint).buildupon()                 .appendqueryparameter("q", bookquery)                 .appendqueryparameter("maxresults", "10")                 .appendqueryparameter("key", api_key)                 .build().tostring();         string result = new googlefetcher().geturl(url);         return result;     }      @override     protected void onpreexecute() {         memptytextview.setvisibility(view.gone);         mprogressbar.setvisibility(view.visible);     }      @override     protected void onpostexecute(string s) {         if (s != null) {             mprogressbar.setvisibility(view.gone);             constructbooksfromjsonresponse(s);             msearchresultlistview.setadapter(new booksearchlistadapter(getactivity(), mbooks));         }     }      @override     protected void oncancelled() {         mprogressbar.setvisibility(view.gone);     }      private void constructbooksfromjsonresponse(string jsonresponse) {         try {             jsonobject obj = new jsonobject(new jsontokener(jsonresponse));             jsonarray jsonarray = obj.getjsonarray(book_items_key);             (int = 0; < jsonarray.length(); i++) {                 jsonobject currentobj = jsonarray.getjsonobject(i);                  string bookid = "";                 if (currentobj.has(book_id_key)) {                     bookid = currentobj.getstring(book_id_key);                 }                  jsonobject volumeinfo = currentobj.getjsonobject(book_volumeinfo_key);                 string booktitle = "";                 if (volumeinfo.has(book_title_key)) {                     booktitle = volumeinfo.getstring(book_title_key);                 }                  jsonarray bookauthors = new jsonarray();                 if (volumeinfo.has(book_authors_key)) {                     bookauthors = volumeinfo.getjsonarray(book_authors_key);                 }                 arraylist<string> authors = new arraylist<>();                 if (bookauthors != null) {                     (int j = 0; j < bookauthors.length(); j++) {                         authors.add(bookauthors.getstring(j));                     }                 }                  string bookdescription = "";                 if (volumeinfo.has(book_description_key)) {                     bookdescription = volumeinfo.getstring(book_description_key);                 }                  jsonobject imagelinks = volumeinfo.getjsonobject(book_imagelinks_key);                 string bookthumbnail = "";                 if (imagelinks.has(book_thumbnail_key)) {                     bookthumbnail = imagelinks.getstring(book_thumbnail_key);                 }                  book b = new book(bookid, authors, booktitle, bookdescription, bookthumbnail);                 mbooks.add(b);             }         } catch (jsonexception e) {             mbooks.clear();         }     } }  private class thumbnaildownloadertask extends asynctask<string, void, bitmap> {      private final weakreference<imageview> imageviewreference;      private thumbnaildownloadertask(imageview imageview) {         imageviewreference = new weakreference<imageview>(imageview);     }      @override     protected bitmap doinbackground(string... params) {         return downloadbitmap(params[0]);     }      private bitmap downloadbitmap(string param) {         httpurlconnection urlconnection = null;         try {             url url = new url(param);             urlconnection = (httpurlconnection) url.openconnection();             int statuscode = urlconnection.getresponsecode();             if (statuscode != httpurlconnection.http_ok) {                 return null;             }             inputstream in = urlconnection.getinputstream();             if (in != null) {                 bitmap bitmap = bitmapfactory.decodestream(in);                 return bitmap;             }         } catch (ioexception e) {             if (urlconnection != null) {                 urlconnection.disconnect();             }         } {             if (urlconnection != null) {                 urlconnection.disconnect();             }         }         return null;     }      @override     protected void onpostexecute(bitmap bitmap) {         if (iscancelled()) {             bitmap = null;         }          if (imageviewreference != null) {             imageview imageview = imageviewreference.get();             if (imageview != null) {                 if (bitmap != null) {                     imageview.setvisibility(view.visible);                     imageview.setimagebitmap(bitmap);                 }             }         }     } } 

and search button triggers search follows:

 @override public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) {     view v = inflater.inflate(r.layout.fragment_addbook, container, false);      msearchedittext = (edittext) v.findviewbyid(r.id.book_title_search_field);     msearchbutton = (button) v.findviewbyid(r.id.search_button);     msearchbutton.setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view v) {             string bookquery = msearchedittext.gettext().tostring();             new searchbooktask().execute(bookquery);         }     }); return v; } 

you try using networkimageview of volley library. more info on image cache. find decent tutorial here , here. should make listview images load correctly.