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Start your free trialJoe Goodall
3,483 PointsNull 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)
Abhishek Amte
3,679 PointsI 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
3,679 PointsI 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);
James Simshaw
28,738 PointsJames Simshaw
28,738 PointsHello,
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.