NotifyDataSetChanged does not work in the fragment after popBackStack ()

After returning a fragment from the previous screen, the adapter update does not work, and the toast in onPostExecute() works fine.

What could be the reason?

I noticed such a thing: if you completely reassign the adapter in onCreateView to else , everything works, although it becomes empty, but everything works.

 @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); activity = getActivity(); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { super.onCreateView(inflater, container, savedInstanceState); View rootView = inflater.inflate(R.layout.screen_two, container, false); mImageLoader = ImageLoader.getInstance(); mImageLoader.init(new UILsettings().getConf(this.getActivity())); // footer footer = inflater.inflate(R.layout.footer, null); btnLoadMore = (Button) footer.findViewById(R.id.loadMore); btnLoadMore.setOnClickListener(LoadMore); categories = (ListView) rootView.findViewById(R.id.lvCategories); categories.addFooterView(footer); if (categoryAdapter == null) { new LoadAllProducts("1").execute(); categoryAdapter = new CategoryAdapter(getActivity(), list, mImageLoader); categories.setAdapter(categoryAdapter); } else { categories.setAdapter(categoryAdapter); categories.onRestoreInstanceState(state); } return rootView; } View.OnClickListener LoadMore = new View.OnClickListener() { @Override public void onClick(View v) { new LoadAllProducts("1").execute(); } }; @Override public void onPause() { state = categories.onSaveInstanceState(); super.onPause(); categories.removeFooterView(footer); } class LoadAllProducts extends AsyncTask<String, String, String> { private String getParams; private JSONArray products; private JSONObject json; private JSON jParser = new JSON(); public LoadAllProducts(String string) { getParams = string; } protected String doInBackground(String... strings) { json = jParser.makeHttpRequest("http://url.getallcats.php", getParams); return null; } protected void onPostExecute(String string) { try { products = json.getJSONArray("category"); for (int i = 0; i < products.length(); i++) { JSONObject c = products.getJSONObject(i); list.add(new Construct( c.getString("name"), c.getString("count"), c.getInt("have"), "http://url.ru/img/" + c.getString("image"))); } } catch (JSONException e) { e.printStackTrace(); } categoryAdapter.notifyDataSetChanged(); Toast.makeText(getActivity(), "Ok", Toast.LENGTH_SHORT).show(); // срабатывает } } 

Implementing a CategoryAdapter adapter

 public class CategoryAdapter extends BaseAdapter { private List<Construct> list; private LayoutInflater inflater; private ImageLoader mImageLoader; public CategoryAdapter(Context context, List<Construct> list, ImageLoader mImageLoader) { this.list = list; this.inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); this.mImageLoader = mImageLoader; } @Override public int getCount() { return list.size(); } @Override public Object getItem(int position) { return list.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder; if (convertView == null) { convertView = inflater.inflate(R.layout.item_category, null); holder = new ViewHolder(); convertView.setTag(holder); holder.ImageProductView = (ImageView) convertView.findViewById(R.id.ImageProductView); holder.tvPost = (TextView) convertView.findViewById(R.id.tvPost); holder.productId = (TextView) convertView.findViewById(R.id.textView); } else { holder = (ViewHolder) convertView.getTag(); } holder.tvPost.setText(list.get(position).getCategoryTitle()); holder.productId.setText(list.get(position).getProductId()); // IMAGE LOADER mImageLoader.displayImage(list.get(position).getProductImage(), holder.ImageProductView, null, new ImageLoadingListener() { 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) { displayedImages.add(imageUri); } else { FadeInBitmapDisplayer.animate(imageView, 200); } } } @Override public void onLoadingCancelled(String uri, View view) { } @Override public void onLoadingStarted(String uri, View view) { FadeInBitmapDisplayer.animate(view, 0); } @Override public void onLoadingFailed(String uri, View view, FailReason fail) { } }); return convertView; } private class ViewHolder { public ImageView ImageProductView; public TextView tvPost; public TextView productId; } } 

And also Construct

 public class Construct { // товар private String productTitle; private String productId; private String productImage; private int productRating; // категория private String categoryTitle; public Construct(String title, String id, int rate, String image) { this.productTitle = title; this.productId = id; this.productImage = image; this.productRating = rate; this.categoryTitle = title; } // товар public String getProductTitle() { return productTitle; } public String getProductId() { return productId; } public String getProductImage() { return productImage; } public int getProductRating() { return productRating; } // категория public String getCategoryTitle() { return categoryTitle; } }