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Android Android Lists and Adapters (2015) Using Parcelable Data Retrieving Parcelable Data

Joe Goodall
Joe Goodall
3,483 Points

Null pointer exception when pressing 7 days button?

Getting a null pointer exception.

Anybody can give me some pointers why?

Thanks in advance.

04-29 17:44:51.095 21179-21179/com.getstrength.stormy E/AndroidRuntime﹕ FATAL EXCEPTION: main Process: com.getstrength.stormy, PID: 21179 java.lang.NullPointerException: id == null at java.util.TimeZone.getTimeZone(TimeZone.java:349) at com.getstrength.stormy.weather.Day.getDayOfTheWeek(Day.java:66) at com.getstrength.stormy.adapters.DayAdapter.getView(DayAdapter.java:72) at android.widget.AbsListView.obtainView(AbsListView.java:2344) at android.widget.ListView.makeAndAddView(ListView.java:1864) at android.widget.ListView.fillDown(ListView.java:698) at android.widget.ListView.fillFromTop(ListView.java:759) at android.widget.ListView.layoutChildren(ListView.java:1673) at android.widget.AbsListView.onLayout(AbsListView.java:2148) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1076) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15596) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2072) at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1829) at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1054) at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5779) at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767) at android.view.Choreographer.doCallbacks(Choreographer.java:580) at android.view.Choreographer.doFrame(Choreographer.java:550) at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753) at android.os.Handler.handleCallback(Handler.java:739) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:135) at android.app.ActivityThread.main(ActivityThread.java:5239) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

Hello,

Could you also post your java files for your Days Activity, as well as your DayAdapter.java and Day.java files? Being able to see these would help us to assist you in debugging this error.

Abhishek Amte
Abhishek Amte
3,679 Points

I too am getting a Null pointer exception for parcelables.length

Here is my code

Day.java

package com.example.abhishek.stormy.weather;

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

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

/**
 * Created by Abhishek on 11-05-2015.
 */
public class Day implements Parcelable {
    private long mTime;
    private String mSummary;
    private double mTemperatureMax;
    private String mIcon;
    private String mTimezone;

    public long getTime() {
        return mTime;
    }

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

    public String getSummary() {
        return mSummary;
    }

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

    public int getTemperatureMax() {
        return (int)Math.round(mTemperatureMax);
    }

    public void setTemperatureMax(double temperatureMax) {
        mTemperatureMax = temperatureMax;
    }

    public String getIcon() {
        return mIcon;
    }

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

    public String getTimezone() {
        return mTimezone;
    }

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

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

    public String getDayOfTheWeek() {
        SimpleDateFormat formatter = new SimpleDateFormat("EEEE");
        formatter.setTimeZone(TimeZone.getTimeZone(mTimezone));
        Date dateTime = new Date(mTime * 1000);
        return formatter.format(dateTime);
    }

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

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeLong(mTime);
        dest.writeString(mSummary);
        dest.writeDouble(mTemperatureMax);
        dest.writeString(mIcon);
        dest.writeString(mTimezone);
    }

    private Day(Parcel in) {
        mTime = in.readLong();
        mSummary = in.readString();
        mTemperatureMax = in.readDouble();
        mIcon = in.readString();
        mTimezone = in.readString();
    }

    public Day() { }

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

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

DailyForecastActivity.java

package com.example.abhishek.stormy.ui;

import android.app.ListActivity;
import android.content.Intent;
import android.os.Parcelable;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;

import com.example.abhishek.stormy.R;
import com.example.abhishek.stormy.adapters.DayAdapter;
import com.example.abhishek.stormy.weather.Day;

import java.util.Arrays;

public class DailyForecastActivity extends ListActivity {

    private Day[] mDays;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_daily_forecast);

        Intent intent = getIntent();
        Parcelable[] parcelables = intent.getParcelableArrayExtra(MainActivity.DAILY_FORECAST);
        mDays = Arrays.copyOf(parcelables, parcelables.length, Day[].class);

        DayAdapter adapter = new DayAdapter(this, mDays);
        setListAdapter(adapter);
    }
}

DayAdapter.java

package com.example.abhishek.stormy.adapters;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.abhishek.stormy.R;
import com.example.abhishek.stormy.weather.Day;

/**
 * Created by Abhishek on 16-05-2015.
 */
public class DayAdapter extends BaseAdapter {

    private Context mContext;
    private Day[] mDays;

    public DayAdapter(Context context, Day[] days){
        mContext = context;
        mDays =days;
    }

    @Override
    public int getCount() {
        return mDays.length;
    }

    @Override
    public Object getItem(int position) {
        return mDays[position];
    }

    @Override
    public long getItemId(int position) {
        return 0; // we arent going to use this. Tag items for easy reference
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;

        if(convertView == null){
            //brand new
            convertView = LayoutInflater.from(mContext).inflate(R.layout.daily_list_item,null);
            holder = new ViewHolder();
            holder.iconImageView = (ImageView)convertView.findViewById(R.id.iconImageView);
            holder.temperatureLabel = (TextView)convertView.findViewById(R.id.temperatureLabel);
            holder.dayLabel = (TextView) convertView.findViewById(R.id.dayNameLabel);

            convertView.setTag(holder);
        }else{
            holder = (ViewHolder)convertView.getTag();
        }

        Day day = mDays[position];

        holder.iconImageView.setImageResource(day.getIconId());
        holder.temperatureLabel.setText(day.getTemperatureMax() + "");
        holder.dayLabel.setText(day.getDayOfTheWeek());

        return convertView;
    }

    private static class ViewHolder{
        ImageView iconImageView; //public by default
        TextView temperatureLabel;
        TextView dayLabel;
    }
}

1 Answer

Abhishek Amte
Abhishek Amte
3,679 Points

I solved my issue. I had to call startActivity after calling the put extra

Intent intent = new Intent(this,DailyForecastActivity.class);
intent.putExtra(DAILY_FORECAST, mForecast.getDailyForecast());
startActivity(intent);