HourAdapter Error "Attempt to invoke method '...' on a null object reference"

package me.johnweland.tempest.ui;

import android.content.Intent;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.View;

import java.util.Arrays;

import butterknife.BindView;
import butterknife.ButterKnife;
import me.johnweland.tempest.R;
import me.johnweland.tempest.adapter.HourAdapter;
import me.johnweland.tempest.weather.Hour;

public class HourlyActivity extends AppCompatActivity {

    private Hour[] mHours;

    @BindView(R.id.recyclerView) RecyclerView mRecyclerView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_hourly);
        ButterKnife.bind(this);

        Intent intent = getIntent();
        Parcelable[] parcelables = intent.getParcelableArrayExtra(MainActivity.HOURLY_FORECAST);

        mHours = Arrays.copyOf(parcelables, parcelables.length, Hour[].class);

        HourAdapter adapter = new HourAdapter(mHours);
        mRecyclerView.setAdapter(adapter);

        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
        mRecyclerView.setLayoutManager(layoutManager);

        mRecyclerView.setHasFixedSize(true);
    }

}

package me.johnweland.tempest.weather;

import android.os.Parcel;
import android.os.Parcelable;

import java.text.SimpleDateFormat;
import java.util.Date;

public class Hour implements Parcelable{
    private long mTime;
    private String mSummary;
    private double mTemperature;
    private String mIcon;
    private String mTimezone;

    public Hour() {
    }

    public long getTime() {
        return mTime;
    }

    public void setTime(long time) {
        mTime = time;
    }

    public String getTimezone() {
        return mTimezone;
    }

    public void setTimezone(String timezone) {
        mTimezone = timezone;
    }

    public String getIcon() {
        return mIcon;
    }

    public int getIconId() {
        return Forecast.getIconId(mIcon);
    }

    public void setIcon(String icon) {
        mIcon = icon;
    }

    public int getTemperature() {
        return (int) Math.round(mTemperature);
    }

    public void setTemperature(double temperature) {
        mTemperature = temperature;
    }

    public String getSummary() {
        return mSummary;
    }

    public void setSummary(String summary) {
        mSummary = summary;
    }

    public String getHour() {
        SimpleDateFormat formatter = new SimpleDateFormat("h a");
        Date date = new Date(mTime * 1000);
        return formatter.format(date);
    }

    @Override
    public int describeContents() {
        return 0; // ignore
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeLong(mTime);
        dest.writeDouble(mTemperature);
        dest.writeString(mSummary);
        dest.writeString(mIcon);
        dest.writeString(mTimezone);
    }
    private Hour(Parcel in) {
        mTime = in.readLong();
        mTemperature = in.readDouble();
        mSummary = in.readString();
        mIcon = in.readString();
        mTimezone = in.readString();
    }

    public static final Creator<Hour> CREATOR = new Creator<Hour>() {
        @Override
        public Hour createFromParcel(Parcel source) {
            return new Hour(source);
        }

        @Override
        public Hour[] newArray(int size) {
            return new Hour[size];
        }
    };
}

package me.johnweland.tempest.adapter;

import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;

import me.johnweland.tempest.R;
import me.johnweland.tempest.weather.Hour;

public class HourAdapter extends RecyclerView.Adapter<HourAdapter.HourViewHolder> {

    private Hour[] mHours;

    public HourAdapter(Hour[] hours) {
        mHours = hours;
    }

    @Override
    public HourViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.hourly_list_item, parent, false);
        HourViewHolder viewHolder = new HourViewHolder(view);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(HourViewHolder holder, int position) {
        holder.bindHour(mHours[position]);
    }

    @Override
    public int getItemCount() {
        return mHours.length;
    }

    public class HourViewHolder extends RecyclerView.ViewHolder {
        public TextView mTimeLabel;
        public TextView mSummaryLabel;
        public TextView mTemperatureLabel;
        public ImageView mIconImageView;

        public HourViewHolder(View itemView) {
            super(itemView);
            mTimeLabel = (TextView) itemView.findViewById(R.id.timeLabel);
            mSummaryLabel = (TextView) itemView.findViewById(R.id.summaryLabel);
            mTemperatureLabel = (TextView) itemView.findViewById(R.id.temperatureLabel);
            mIconImageView = (ImageView) itemView.findViewById(R.id.iconImageView);
        }

        public void bindHour(Hour hour){
            mTimeLabel.setText(hour.getHour());
            mSummaryLabel.setText(hour.getSummary());
            mTemperatureLabel.setText(hour.getTemperature() + "");
            mIconImageView.setImageResource(hour.getIconId());
        }

    }
}

package me.johnweland.tempest.ui;

import android.app.Activity;

import android.content.Context;
import android.content.Intent;
import android.graphics.drawable.Drawable;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import me.johnweland.tempest.R;
import me.johnweland.tempest.ui.AlertDialogFragment;
import me.johnweland.tempest.weather.Current;
import me.johnweland.tempest.weather.Day;
import me.johnweland.tempest.weather.Forecast;
import me.johnweland.tempest.weather.Hour;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class MainActivity extends Activity {
    public static final String TAG = MainActivity.class.getSimpleName();
    public static final String DAILY_FORECAST = "DAILY_FORECAST";
    public static final String HOURLY_FORECAST = "HOURLY_FORECAST";
    private Forecast mForecast;

    @BindView(R.id.timeLabel) TextView mTimeLabel;
    @BindView(R.id.temperatureLabel) TextView mTemperatureLabel;
    @BindView(R.id.humidityValue) TextView mHumidityValue;
    @BindView(R.id.precipValue) TextView mPrecipValue;
    @BindView(R.id.summaryLabel) TextView mSummaryLabel;
    @BindView(R.id.iconImageView) ImageView mIconImageView;
    @BindView(R.id.refreshImageView) ImageView mRefreshImageView;
    @BindView(R.id.progressBar) ProgressBar mProgressBar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        mProgressBar.setVisibility(View.INVISIBLE);

        final double latitude = 37.8267;
        final double longitude = -122.423;

        mRefreshImageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                getForecast(latitude, longitude);
            }
        });

        getForecast(latitude, longitude);
    }

    private void getForecast(double latitude, double longitude) {
        String apiKey = " APIKEY ";
        String forecastURL = "https://api.forecast.io/forecast/" +
                apiKey +
                "/" +
                latitude +
                "," +
                longitude;
        if(isNetworkAvailable()) {

            toggleRefresh();
            OkHttpClient client = new OkHttpClient();
            Request request = new Request.Builder()
                    .url(forecastURL)
                    .build();

            Call call = client.newCall(request);
            call.enqueue(new Callback() {
                @Override
                public void onFailure(Call call, IOException e) {
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            toggleRefresh();
                        }
                    });

                    alertUserAboutError();
                }

                @Override
                public void onResponse(Call call, Response response) throws IOException {
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            toggleRefresh();
                        }
                    });
                    try {
                        String jsonData = response.body().string();
                        if (response.isSuccessful()) {
                            mForecast = parseForecastDetails(jsonData);
                            runOnUiThread(new Runnable() {
                                @Override
                                public void run() {
                                    updateDisplay();
                                }
                            });
                        } else {
                            alertUserAboutError();
                        }
                    }
                    catch (IOException e) {
                        Log.e(TAG, "Exception caught: ",e);
                    }
                    catch (JSONException e) {
                        Log.e(TAG, "Exception caught: ",e);
                    }
                }
            });

        } else {
            Toast.makeText(this, R.string.network_unavailable_message, Toast.LENGTH_LONG).show();
        }
    }

    private void toggleRefresh() {
        if (mProgressBar.getVisibility() == View.INVISIBLE) {
            mProgressBar.setVisibility(View.VISIBLE);
            mRefreshImageView.setVisibility(View.INVISIBLE);
        } else {
            mProgressBar.setVisibility(View.INVISIBLE);
            mRefreshImageView.setVisibility(View.VISIBLE);
        }
    }

    private void updateDisplay() {
        Current current = mForecast.getCurrently();
        mTemperatureLabel.setText(current.getTemperature() + "");
        mTimeLabel.setText("At " + current.getFormattedTime() + " it will be");
        mHumidityValue.setText(current.getHumidity() + "");
        mPrecipValue.setText(current.getPrecipChance() + "%");
        mSummaryLabel.setText((current.getSummary()));
        Drawable drawable = getResources().getDrawable(current.getIconId());
        mIconImageView.setImageDrawable(drawable);
    }

    private Forecast parseForecastDetails(String jsonData) throws JSONException {
        Forecast forecast = new Forecast();
        forecast.setCurrently(getCurrentDetails(jsonData));
        forecast.setHourly(getHourlyDetails(jsonData));
        forecast.setDaily(getDailyDetails(jsonData));
        return forecast;
    }

    private Day[] getDailyDetails(String jsonData) throws JSONException {
        JSONObject forecast = new JSONObject(jsonData);
        String timezone = forecast.getString("timezone");

        JSONObject daily = forecast.getJSONObject("daily");
        JSONArray data = daily.getJSONArray("data");

        Day[] days = new Day[data.length()];
        for ( int i = 0; i < data.length(); i++ ) {
            JSONObject jsonDay = data.getJSONObject(i);
            Day day = new Day();
            day.setSummary(jsonDay.getString("summary"));
            day.setTempMax(jsonDay.getDouble("temperatureMax"));
            day.setTempMin(jsonDay.getDouble("temperatureMin"));
            day.setIcon(jsonDay.getString("icon"));
            day.setTime(jsonDay.getLong("time"));
            day.setTimezone(timezone);

            days[i] = day;
        }
        return days;
    }

    private Hour[] getHourlyDetails(String jsonData) throws JSONException {
        JSONObject forecast = new JSONObject(jsonData);
        String timezone = forecast.getString("timezone");

        JSONObject hourly = forecast.getJSONObject("hourly");
        JSONArray data = hourly.getJSONArray("data");

        Hour[] hours = new Hour[data.length()];
        for ( int i = 0; i < data.length(); i++ ) {
            JSONObject jsonHour = data.getJSONObject(i);
            Hour hour = new Hour();
            hour.setSummary(jsonHour.getString("summary"));
            hour.setTemperature(jsonHour.getDouble("temperature"));
            hour.setIcon(jsonHour.getString("icon"));
            hour.setTime(jsonHour.getLong("time"));
            hour.setTimezone(timezone);

            hours[i] = hour;
        }
        return hours;
    }

    private Current getCurrentDetails(String jsonData) throws JSONException {
        JSONObject forecast = new JSONObject(jsonData);
        String timezone = forecast.getString("timezone");

        JSONObject currently = forecast.getJSONObject("currently");
        Current current = new Current();
        current.setHumidity(currently.getDouble("humidity"));
        current.setTime(currently.getLong("time"));
        current.setIcon(currently.getString("icon"));
        current.setPrecipChance(currently.getDouble("precipProbability"));
        current.setSummary(currently.getString("summary"));
        current.setTemperature(currently.getDouble("temperature"));
        current.setTimezone(timezone);

        return current;
    }

    private boolean isNetworkAvailable() {
        ConnectivityManager manager = (ConnectivityManager)
                getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkinfo = manager.getActiveNetworkInfo();

        boolean isAvalable = false;
        if(networkinfo != null && networkinfo.isConnected()) {
            isAvalable = true;
        }

        return isAvalable;
    }

    private void alertUserAboutError() {
        AlertDialogFragment dialog = new AlertDialogFragment();
        dialog.show(getFragmentManager(), "error_dialog");
    }

    @OnClick (R.id.dailyButton)
    public void startDailyActivity (View view) {
        Intent intent = new Intent(this, DailyActivity.class);
        intent.putExtra(DAILY_FORECAST, mForecast.getDaily());
        startActivity(intent);
    }

    @OnClick (R.id.hourlyButton)
    public void startHourlyActivity (View view) {
        Intent intent = new Intent(this, HourlyActivity.class);
        intent.putExtra(HOURLY_FORECAST, mForecast.getHourly());
        startActivity(intent);
    }
}