Update and control multiple CountDownTimer in RecyclerView (pause, resume, delete)

Question

I've implemented to my Android app multiple countdown timers with Service. CountDownTimer is running with service, thus data to fragment is being passed with BroadcastReceiver.

I would like to add each timer as a separate item to the RecyclerView in the fragment and be able to update it as timer is ticking and also to control it - pause, resume, add 1 min and delete.

At the moment the problem is that each second that timer is running, new item is added to RecyclerView and I'm not able to control it - pause, resume and ect.

Service Class:

public int onStartCommand(Intent intent, int flags, int startId) {


        if (intent.getAction().equals(Constants.ACTION.START_FOREGROUND_ACTION)){

            HandlerThread thread = new HandlerThread("ServiceStartArguments",
                    android.os.Process.THREAD_PRIORITY_BACKGROUND);
            thread.setName(nameOfFood);
            thread.start();

            mServiceLooper = thread.getLooper();
            mServiceHandler = new ServiceHandler(mServiceLooper);
    }

     private final class ServiceHandler extends Handler {
        public ServiceHandler(Looper looper) {
            super(looper);

        }

        @Override
        public void handleMessage(Message msg) {
            // Normally we would do some work here, like download a file.

            Thread.currentThread().setName(nameOfFood);

            try {
                showCountDownTimer(enteredTimeFormatted);
            } catch (Exception e) {
                // Restore interrupt status.
                Thread.currentThread().interrupt();
            }

            stopSelf(msg.arg1);
        }

    private void showCountDownTimer(long number) {

        String normalStartTime = String.format(
                "%02d:%02d:%02d",
                TimeUnit.MILLISECONDS.toHours(number),
                TimeUnit.MILLISECONDS.toMinutes(number) -
                        TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS.toHours(number)),
                TimeUnit.MILLISECONDS.toSeconds(number) -
                        TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(number)));

        Intent timerStartInfoIntent = new Intent(TIMER_START_INFO);
        timerStartInfoIntent.putExtra("VALUE", normalStartTime);
        timerStartInfoIntent.putExtra("NAME_FOOD", nameOfFood);
        LocalBroadcastManager.getInstance(NotificationService.this).sendBroadcast(timerStartInfoIntent);


        CountDownTimer timer = new CountDownTimer(number, 1000) {

            @Override
            public void onTick(long millisUntilFinished) {
                timeLeft = millisUntilFinished;


                counter = millisUntilFinished / 1000;

                normalTime = String.format(
                        "%02d:%02d:%02d",
                        TimeUnit.MILLISECONDS.toHours(timeLeft),
                        TimeUnit.MILLISECONDS.toMinutes(timeLeft) -
                                TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS.toHours(timeLeft)),
                        TimeUnit.MILLISECONDS.toSeconds(timeLeft) -
                                TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(timeLeft)));

                Intent timerInfoIntent = new Intent(TIME_INFO);
                timerInfoIntent.putExtra("VALUE", normalTime);
                timerInfoIntent.putExtra("NAME_FOOD", nameOfFood);
                LocalBroadcastManager.getInstance(NotificationService.this).sendBroadcast(timerInfoIntent);

            }

            @Override
            public void onFinish() {
                counter = 0;

                Intent timerFinishInfoIntent = new Intent(TIMER_FINISH_INFO);
                LocalBroadcastManager.getInstance(NotificationService.this).sendBroadcast(timerFinishInfoIntent);
            }
        };

        timer.start();
    }

Adapter Class:

public class TimerRecyclerViewAdapter extends RecyclerView.Adapter<TimerRecyclerViewAdapter.MyViewHolder> {

final private Context mContext;
public List<ModelTimer> mModelTimerList;
private final List<MyViewHolder> listHolder;


public TimerRecyclerViewAdapter(List<ModelTimer> modelTimerList, Context context) {
    super();
    this.mContext = context;
    this.mModelTimerList = modelTimerList;
    listHolder = new ArrayList<>();
}


public class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
    public final TextView nameTextView;
    public final TextView timerTextView;
    public final Button pauseBtn;
    public final Button addMinBtn;
    public final Button deleteBtn;
    ModelTimer mModelTimer;


    public MyViewHolder(View itemView) {
        super(itemView);
        nameTextView = (TextView) itemView.findViewById(R.id.active_timer_name);
        timerTextView = (TextView) itemView.findViewById(R.id.active_timer_timeLeft);
        pauseBtn = (Button) itemView.findViewById(R.id.active_timer_btn_pause);
        pauseBtn.setOnClickListener(this);
        addMinBtn = (Button) itemView.findViewById(R.id.active_timer_btn_addMin);
        addMinBtn.setOnClickListener(this);
        deleteBtn = (Button) itemView.findViewById(R.id.active_timer_btn_delete);
        deleteBtn.setOnClickListener(this);
    }

    public void setData (ModelTimer modelTimer){
        this.mModelTimer = modelTimer;
        timerTextView.setText(modelTimer.expirationTime);
        nameTextView.setText(modelTimer.name);
    }

    @Override
    public void onClick(View v) {
      // TODO 
    }
}

@Override
public TimerRecyclerViewAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    if (parent instanceof RecyclerView) {
        View v = LayoutInflater.from(parent.getContext()).inflate(
                R.layout.item_active_timer,
                parent,
                false);
        v.setFocusable(true);
        return new MyViewHolder(v);
    } else {
        throw new RuntimeException("No bound to RecyclerViewSelection");
    }
}

@Override
public void onBindViewHolder(TimerRecyclerViewAdapter.MyViewHolder holder, int position) {
    holder.setData(mModelTimerList.get(position));
    synchronized (listHolder){
        listHolder.add(holder);
    }
}

@Override
public int getItemCount() {
    return mModelTimerList.size();
}

Here I tried to create a method that will be upgrading each second a timer on specific position instead of adding new item to RecyclerView each time that timer is ticking.

public void swap(List<ModelTimer> modelTimerList){
    mModelTimerList.clear();
    mModelTimerList.addAll(modelTimerList);
    notifyItemChanged(???);
}

public void delete() {
    mModelTimerList.clear();
    notifyDataSetChanged();
}
}

Fragment with RecyclerView:

public class ActiveTimersFragment extends Fragment {

private RecyclerView mRecyclerView;
private TimerRecyclerViewAdapter mAdapter;
private ArrayList<ModelTimer> listOfTimers;
private TimerStatusReceiver mTimerStatusReceiver;

private static final String ARG_SECTION_NUMBER = "section_number";

public ActiveTimersFragment() {
}

public static ActiveTimersFragment newInstance(int sectionNumber) {
    ActiveTimersFragment activeTimersFragment = new ActiveTimersFragment();
    Bundle args = new Bundle();
    args.putInt(ARG_SECTION_NUMBER, sectionNumber);
    activeTimersFragment.setArguments(args);
    return activeTimersFragment;
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_active_timers, container, false);

    mRecyclerView = (RecyclerView) view.findViewById(R.id.fragment_active_timers_recycler_view);
    mTimerStatusReceiver = new TimerStatusReceiver();

    listOfTimers = new ArrayList<>();

    return view;
}

@Override
public void onResume() {
    super.onResume();
    LocalBroadcastManager.getInstance(getActivity()).registerReceiver(
            mTimerStatusReceiver, new IntentFilter(NotificationService.TIME_INFO));
    LocalBroadcastManager.getInstance(getActivity()).registerReceiver(
            mTimerStatusReceiver, new IntentFilter(NotificationService.TIMER_START_INFO));
    LocalBroadcastManager.getInstance(getActivity()).registerReceiver(
            mTimerStatusReceiver, new IntentFilter(NotificationService.TIMER_FINISH_INFO));

}

@Override
public void onPause() {
    super.onPause();
    LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(mTimerStatusReceiver);

}

private class TimerStatusReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {

        if (intent != null && intent.getAction().equals(NotificationService.TIME_INFO)) {

            ModelTimer modelTimer = new ModelTimer();

            if (intent.hasExtra("VALUE")) {
                modelTimer.setexpirationTime(intent.getStringExtra("VALUE"));
            }
            if (intent.hasExtra("NAME_FOOD")) {
                modelTimer.setName(intent.getStringExtra("NAME_FOOD"));
            }

            listOfTimers.add(modelTimer);
            mAdapter = new TimerRecyclerViewAdapter(listOfTimers, getActivity());
            mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
            // Not working
            // mAdapter.swap(listOfTimers);
            mRecyclerView.setAdapter(mAdapter);

        }

        if (intent != null && intent.getAction().equals(NotificationService.TIMER_FINISH_INFO)) {
            mAdapter.delete();
        }

    }
}
}

Answer 1

Your whole implementation of recyclerview adapter is wrong. In onBindViewHolder() you are adding new item. onBindViewHolder is called when RecyclerView tries to show new item. So it keeps on iterating, if you add new item in onBindViewHolder. Also, you should use the onBindViewHolder to set the views values in ViewHolder class. Check the whole adapter implementation.

   public class TimerRecyclerViewAdapter extends RecyclerView.Adapter<TimerRecyclerViewAdapter.MyViewHolder> {

    final private Context mContext;
    public List<ModelTimer> mModelTimerList;


    public TimerRecyclerViewAdapter(List<ModelTimer> modelTimerList, Context context) {
        super();
        this.mContext = context;
        this.mModelTimerList = modelTimerList;

    }


    public class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
        public final TextView nameTextView;
        public final TextView timerTextView;
        public final Button pauseBtn;
        public final Button addMinBtn;
        public final Button deleteBtn;



        public MyViewHolder(View itemView) {
            super(itemView);
            nameTextView = (TextView) itemView.findViewById(R.id.active_timer_name);
            timerTextView = (TextView) itemView.findViewById(R.id.active_timer_timeLeft);
            pauseBtn = (Button) itemView.findViewById(R.id.active_timer_btn_pause);
            pauseBtn.setOnClickListener(this);
            addMinBtn = (Button) itemView.findViewById(R.id.active_timer_btn_addMin);
            addMinBtn.setOnClickListener(this);
            deleteBtn = (Button) itemView.findViewById(R.id.active_timer_btn_delete);
            deleteBtn.setOnClickListener(this);
        }


        @Override
        public void onClick(View v) {
            // TODO
        }
    }


    @Override
    public TimerRecyclerViewAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        if (parent instanceof RecyclerView) {
            View v = LayoutInflater.from(parent.getContext()).inflate(
                    R.layout.item_active_timer,
                    parent,
                    false);
            v.setFocusable(true);
            return new MyViewHolder(v);
        } else {
            throw new RuntimeException("No bound to RecyclerViewSelection");
        }
    }

    @Override
    public void onBindViewHolder(TimerRecyclerViewAdapter.MyViewHolder holder, int position) {

        ModelTimer modelTimer=mModelTimerList.get(position);
        holder.timerTextView.setText(modelTimer.expirationTime);
        holder.nameTextView.setText(modelTimer.name);
    }

    @Override
    public int getItemCount() {
        return mModelTimerList.size();
    }