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Start your free trialKyle Derrick
7,746 Pointsjava.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)'
Hello,
Thank you in advance for any help given.
I am getting this error when I attempt to run my weather app. I realize it is due to the "iconString" object on Forecast.Java being null, but I cannot locate where I made an error that is causing it to be null.
Here is the error log:
FATAL EXCEPTION: main Process: com.epicodus.theweatherapp, PID: 2980 java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
at com.epicodus.theweatherapp.weather.Forecast.getIconId(Forecast.java:47)
at com.epicodus.theweatherapp.weather.Day.getIconId(Day.java:62)
at com.epicodus.theweatherapp.Adapters.DayAdapter.getView(DayAdapter.java:58)
at android.widget.AbsListView.obtainView(AbsListView.java:2346)
at android.widget.ListView.makeAndAddView(ListView.java:1875)
at android.widget.ListView.fillDown(ListView.java:702)
at android.widget.ListView.fillFromTop(ListView.java:763)
at android.widget.ListView.layoutChildren(ListView.java:1684)
at android.widget.AbsListView.onLayout(AbsListView.java:2148)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1079)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at com.android.internal.policy.PhoneWindow$DecorView.onLayout(PhoneWindow.java:2678)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2171)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1931)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1107)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6013)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:606)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
I will also post my Forecast.Java, Day.Java and DayAdapter.Java (as I believe one of those is where the error lies).
public class Forecast {
public static final String TAG = Forecast.class.getSimpleName();
private Current mCurrent;
private Hour[] mHourlyForecast;
private Day[] mDailyForecast;
public Current getCurrent() {
return mCurrent;
}
public void setCurrent(Current mCurrent) {
this.mCurrent = mCurrent;
}
public Hour[] getHourlyForecast() {
return mHourlyForecast;
}
public void setHourlyForecast(Hour[] mHourlyForecast) {
this.mHourlyForecast = mHourlyForecast;
}
public Day[] getDailyForecast() {
return mDailyForecast;
}
public void setDailyForecast(Day[] mDailyForecast) {
this.mDailyForecast = mDailyForecast;
}
public static int getIconId(String iconString) {
int iconId = R.mipmap.clear_day;
if (iconString.equals("clear-day")) {
iconId = R.mipmap.clear_day;
}
else if (iconString.equals("clear-night")) {
iconId = R.mipmap.clear_night;
}
else if (iconString.equals("rain")) {
iconId = R.mipmap.rain;
}
else if (iconString.equals("snow")) {
iconId = R.mipmap.snow;
}
else if (iconString.equals("sleet")) {
iconId = R.mipmap.sleet;
}
else if (iconString.equals("wind")) {
iconId = R.mipmap.wind;
}
else if (iconString.equals("fog")) {
iconId = R.mipmap.fog;
}
else if (iconString.equals("cloudy")) {
iconId = R.mipmap.cloudy;
}
else if (iconString.equals("partly-cloudy-day")) {
iconId = R.mipmap.partly_cloudy;
}
else if (iconString.equals("partly-cloudy-night")) {
iconId = R.mipmap.cloudy_night;
}
Log.d(TAG, iconId + ": THIS SHOULD NOT BE NULL BUT IT MAY BE" );
return iconId;
}
}
public class Day implements Parcelable {
private long mTime;
private String mSummary;
private double mTemperatureMax;
private String mIcon;
private String mTimezone;
public static final String TAG = Day.class.getSimpleName();
public long getTime() {
return mTime;
}
public void setTime(long mTime) {
this.mTime = mTime;
}
public String getSummary() {
return mSummary;
}
public void setSummary(String mSummary) {
this.mSummary = mSummary;
}
public int getTemperatureMax() {
return (int)Math.round(mTemperatureMax);
}
public void setTemperatureMax(double mTemperatureMax) {
this.mTemperatureMax = mTemperatureMax;
}
public String getIcon() {
return mIcon;
}
public void setIcon(String mIcon) {
this.mIcon = mIcon;
}
public String getTimezone() {
return mTimezone;
}
public void setTimezone(String mTimezone) {
this.mTimezone = mTimezone;
}
public int getIconId() {
Log.d(TAG, Forecast.getIconId(mIcon) + "");
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];
}
};
}
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; //Will not be used. Can be used to 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.temperatureLabelTextView = (TextView) convertView.findViewById(R.id.temperatureLabelTextView);
holder.dayLabelTextView = (TextView) convertView.findViewById(R.id.dayNameLabelTextView);
convertView.setTag(holder);
}
else {
holder = (ViewHolder) convertView.getTag();
}
Day day = mDays[position];
holder.iconImageView.setImageResource(day.getIconId());
holder.temperatureLabelTextView.setText(day.getTemperatureMax() + "");
holder.dayLabelTextView.setText(day.getDayOfTheWeek());
return convertView;
}
private static class ViewHolder {
ImageView iconImageView;
TextView temperatureLabelTextView;
TextView dayLabelTextView;
}
}
Thank you again and please let me know if any additional info is needed to provide advice.
3 Answers
Kyle Derrick
7,746 PointsLucas,
For me, it was an issue on MainActivity. When creating the day object, I had neglected to get the icon String. Once I added: "day.setIcon(jsonDay.getString("icon"));" it worked as desired.
Hope this helps
Kyle Derrick
7,746 PointsNevermind.
I have figured it out. Sorry if anyone wasted time looking at this.
Lucas Assalti
3,459 PointsHey, i have this error too, what do you did to resolve?
Joseph Ngo
10,020 PointsI am having the same problem and it arises because the daily forecast array is empty when it gets parced to DailyForecastActivity. I don't know how to fix this so any help would be appreciated.
Lucas Assalti
3,459 PointsLucas Assalti
3,459 PointsThis worked for me. Thank u Kyle :)