Well adapters in Android are basically a bridge between the UI components and the data source that fill data into the UI Component For example, Lists (UI Component) get populated by using a list adapter, from a data source array.
Implement the getItemViewType() and getViewTypeCount() for your adapter: @Override public int getViewTypeCount() { return 2; //return 2, you have two types that the getView() method will return, normal(0) and for the last row(1) } and: @Override public int getItemViewType(int position) { return (position == this.getCount() – 1) ? 1 : 0; //if we are at … Read more
Here are the key ideas when a RadioButton is checked we must call notifyDataSetChanged(), so that all views get updated. when a RadioButton is checked we must set a selectedPosition, to keep track of which RadioButton is selected Views are recycled inside ListViews. Therefore, their absolute position changes in the ListView. Therefore, inside ListAdapter#getView(), we … Read more
You can use the notifyItemChanged(int position) method from the RecyclerView.Adapter class. From the documentation: Notify any registered observers that the item at position has changed. Equivalent to calling notifyItemChanged(position, null);. This is an item change event, not a structural change event. It indicates that any reflection of the data at position is out of date … Read more
You didn’t attach the adapter because you create it after you try to attach it: mRecyclerView.setAdapter(mAdapter); // Here, mAdapter is null mAdapter = new CountryAdapter(CountryManager.getInstance().getCountries(), R.layout.card_layout, getActivity());
RecyclerView’s Adapter doesn’t come with many methods otherwise available in ListView’s adapter. But your swap can be implemented quite simply as: class MyRecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { List<Data> data; … public void swap(ArrayList<Data> datas) { data.clear(); data.addAll(datas); notifyDataSetChanged(); } } Also there is a difference between list.clear(); list.add(data); and list = newList; The first is reusing … Read more
To those still having problems, I solved it this way: List<Item> newItems = databaseHandler.getItems(); ListArrayAdapter.clear(); ListArrayAdapter.addAll(newItems); ListArrayAdapter.notifyDataSetChanged(); databaseHandler.close(); I first cleared the data from the adapter, then added the new collection of items, and only then set notifyDataSetChanged(); This was not clear for me at first, so I wanted to point this out. Take note … Read more
You can send in the ImageView to the task constructor and keep a reference to the image path there. Now at onPostExecute, check if the current tag of the ImageView is the same as the one that you started with. If yes, then set the image. If no, don’t do anything. However, this means that … Read more
Can anyone explain why findViewById is so slow? And why View Holder Pattern is faster? When you are not using Holder so getView() method will call findViewById() as many times as you row(s) will be out of View. So if you have 1000 rows in List and 990 rows will be out of View then … Read more
in your adapter add new function for update the list public void updateList(List<DataHolder> list){ displayedList = list; notifyDataSetChanged(); } add textWatcher for search lets say you are using Edittext as search field searchField.addTextChangedListener(new TextWatcher() { @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // TODO Auto-generated method stub } @Override public … Read more