I'm in a fragment trying to updated my recycler view, after querying Parse for some data. In the done method of the query I call notifyDataSetChagned, but the list is never displayed
package com.garciaericn.t2d.fragments; public class DevicesCardViewFragment extends Fragment implements View.OnClickListener { private OnFragmentInteractionListener mListener; private BatteryHelper mBatteryHelper; Intent mBatteryStatus; private RecyclerView mRecyclerView; private DeviceAdapter mAdapter; private RecyclerView.LayoutManager mLayoutManager; private List<Device> mDevices; public DevicesCardViewFragment() { // Required empty public constructor mDevices = new ArrayList<Device>(); } public static DevicesCardViewFragment newInstance() { // Bundle parameters is necessary return new DevicesCardViewFragment(); } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Get arguments getDevices(); mBatteryHelper = new BatteryHelper(getActivity()); IntentFilter intentFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED); mBatteryStatus = getActivity().registerReceiver(null, intentFilter); // Update stats of current device. Toast.makeText(getActivity(), "Battery level: " + mBatteryHelper.getCurrentBatteryLevel() + "%", Toast.LENGTH_LONG).show(); // Update device stats } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_devices_list, container, false); mListener.showAd(); // Obtain recycler view mRecyclerView = (RecyclerView) view.findViewById(R.id.devices_recycler_view); mRecyclerView.setHasFixedSize(true); mAdapter = new DeviceAdapter(getActivity(), mDevices); // Set adapter mRecyclerView.setAdapter(mAdapter); // Set layout manager mLayoutManager = new LinearLayoutManager(getActivity()); mRecyclerView.setLayoutManager(mLayoutManager); return view; } @Override public void onAttach(Activity activity) { super.onAttach(activity); try { mListener = (OnFragmentInteractionListener) activity; } catch (ClassCastException e) { throw new ClassCastException(activity.toString() + " must implement OnFragmentInteractionListener"); } } @Override public void onDetach() { super.onDetach(); mListener = null; } public List<Device> getDevices() { ParseQuery<Device> query = ParseQuery.getQuery(Device.DEVICES); // new ParseQuery<Device>(Device.DEVICES); query.whereEqualTo("deviceUser", ParseUser.getCurrentUser()); query.findInBackground(new FindCallback<Device>() { @Override public void done(List<Device> devices, ParseException e) { if (e == null) { // Loop through return devices for (Device device : devices) { Device currentDevice = new Device(); currentDevice.setDeviceName(device.getDeviceName()); currentDevice.setBatteryLevel(device.getBatteryLevel()); currentDevice.setIsCharging(device.isCharging()); mDevices.add(currentDevice); } mAdapter.notifyDataSetChanged(); } else { // Something went wrong Toast.makeText(getActivity(), "Error: " + e.toString(), Toast.LENGTH_LONG).show(); } } }); return mDevices; } @Override public void onClick(View v) { // Click events go here } public static DevicesCardViewFragment newInstance(List<Device> mDevices) { DevicesCardViewFragment fragment = new DevicesCardViewFragment(); Bundle args = new Bundle(); return fragment; } public interface OnFragmentInteractionListener { public void showAd(); } } My recyclerViewAdapter looks like this:
package com.garciaericn.t2d.data; public class DeviceAdapter extends RecyclerView.Adapter<DeviceAdapter.MyViewHolder> { private final LayoutInflater inflater; List<Device> data = Collections.emptyList(); public DeviceAdapter(Context context, List<Device> data) { inflater = LayoutInflater.from(context); this.data = data; } @Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = inflater.inflate(R.layout.card_layout, parent, false); MyViewHolder holder = new MyViewHolder(view); return holder; } @Override public void onBindViewHolder(MyViewHolder holder, int position) { Device device = data.get(position); holder.deviceNameTV.setText(device.getDeviceName()); holder.batteryLevelTV.setText(device.getBatteryLevel()); } @Override public int getItemCount() { return 0; } public static class MyViewHolder extends RecyclerView.ViewHolder { // Temp data set private String[] mDataset; TextView deviceNameTV; TextView batteryLevelTV; public MyViewHolder(View itemView) { super(itemView); deviceNameTV = (TextView) itemView.findViewById(R.id.device_name_tv); batteryLevelTV = (TextView) itemView.findViewById(R.id.battery_level_tv); } } } 
