android-ImageView in listview not showing image when scroll up and down -

i'm getting images internet via universalimagedownloader , i'm using viewholder showing them :

public class listadapter2 extends baseadapter {     activity activity;     public arraylist<hashmap<string, string>> list;      public listadapter2(activity activity, arraylist<hashmap<string, string>> list) {         super();         this.activity = getactivity();         this.list = list;     }      public hashmap<string, string> geting(int position) {         return list.get(position);     }      public void addall(arraylist<hashmap<string, string>> result) {         if (this.list == null) {             this.list = result;         } else {             this.list.addall(result);         }         notifydatasetchanged();     }      public int getcount() {         return list.size();     }      public object getitem(int position) {         return list.get(position);     }      public long getitemid(int arg0) {         return 0;     }      private class viewholder {         imageview img;     }      public view getview(int position, view convertview, viewgroup parent) {         final viewholder holder;         layoutinflater inflater = activity.getlayoutinflater();         if (convertview == null) {             convertview = inflater.inflate(r.layout.row_grids, null);             holder = new viewholder();             holder.img = (imageview) convertview.findviewbyid(r.id.image);             convertview.settag(holder);         } else {             holder = (viewholder) convertview.gettag();         }          item = list.get(position);          if(item.get("img").length()>0)             imageloader.displayimage("http://website.com/img/" + item.get("img"), holder.img, options,                 imagelistener);         else             holder.img.setimagedrawable(getresources().getdrawable(r.drawable.fix));         }          return convertview;     }      public void clear() {         if (this.list.size() > 0)             this.list.clear();     } }  private static class imagedisplaylistener extends simpleimageloadinglistener {      static final list<string> displayedimages = collections.synchronizedlist(new linkedlist<string>());      @override     public void onloadingcomplete(string imageuri, view view, bitmap loadedimage) {         if (loadedimage != null) {             imageview imageview = (imageview) view;             boolean firstdisplay = !displayedimages.contains(imageuri);             if (firstdisplay) {                 fadeinbitmapdisplayer.animate(imageview, 500);                 displayedimages.add(imageuri);             }         }     } } 

i've tested 3 phones , works fine when test on friends't phone, times 1 of images not showing .

for example, when come activity , shows images , when scroll down last items not showing anymore , scroll up, 1 of images that's been showing before not showing anymore , shows default image .

is there wrong code ? way, i've 4 tabs , happens in tabs .

thanks

the problem displayimage method, not encode url cases ..the better approch should use picasso library

if using android studio add

compile 'com.squareup.picasso:picasso:2.5.2'

in build.gradle file , sync:

or else picasso site download jar file eclipse

after able use picasso library , replace lines

if(item.get("img").length()>0)         imageloader.displayimage("http://website.com/img/" + item.get("img"), holder.img, options,             imagelistener);     else         holder.img.setimagedrawable(getresources().getdrawable(r.drawable.fix));     }   string imgurl = "http://website.com/img/" + item.get("img");     if (!imgurl.equals(""))         picasso.with(activity).load(imgurl).into(holder.img);     else         picasso.with(activity).load(r.drawable.fix).into(holder.img );