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
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
Obtaining the Context in the constructor has (at least) three advantages: You only do it once, not every time, getView() is called. You can use it for other purposes too, when needed. It also works, when parent is null. However, if you don’t have any problems with your solution, you might as well stick to … Read more
The recyclerview:1.2.0-alpha02 introduced the MergeAdapter that has been renamed to ConcatAdapter with recyclerview:1.2.0-alpha04. This RecyclerView Adapter can combine multiple adapters linearly. Something like: FirstAdapter adapter1 = …; SecondAdapter adapter2 = …; ConcatAdapter merged = new ConcatAdapter(adapter1, adapter2); recyclerView.setAdapter(mergedAdapter); As part of this change the method getAdapterPosition() was deprecated because the name is confusing when adapters … Read more
Changed means the data set changed. Individual items updated, or items were added or removed. Invalidated means the data source is no longer available.
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
Use this : public View getViewByPosition(int pos, ListView listView) { final int firstListItemPosition = listView.getFirstVisiblePosition(); final int lastListItemPosition = firstListItemPosition + listView.getChildCount() – 1; if (pos < firstListItemPosition || pos > lastListItemPosition ) { return listView.getAdapter().getView(pos, null, listView); } else { final int childIndex = pos – firstListItemPosition; return listView.getChildAt(childIndex); } }
There’s actually a specific method that callsback with the RecyclerView that attaches to the adapter. Just override the onAttachedToRecylerView(RecyclerView recyclerView) method. public class Adapter_RV extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ RecyclerView mRecyclerView; @Override public void onAttachedToRecyclerView(RecyclerView recyclerView) { super.onAttachedToRecyclerView(recyclerView); mRecyclerView = recyclerView; } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { return null; } @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, … Read more
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.
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