java.lang.NullPointerException while setting time

Question

TimePicker shows up, but when i try to select time. It throws me the exception below.

TimeFragment Class.

import java.util.Calendar;
import com.actionbarsherlock.app.SherlockDialogFragment;
import android.app.Dialog;
import android.app.TimePickerDialog;
import android.content.Context;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.widget.TimePicker;

public class TimePickerFragment extends SherlockDialogFragment implements TimePickerDialog.OnTimeSetListener
{
    private TimePickedListener mListener;
    static int hour;
    static int minute;
    static Context mContext;

    public static TimePickerFragment newInstance(Context context, TimePickedListener listener, Calendar now)
    {
        TimePickerFragment dialog = new TimePickerFragment();
        mContext = context;
        hour = now.get(Calendar.HOUR_OF_DAY);
        minute = now.get(Calendar.MINUTE);

        return dialog;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        return new TimePickerDialog(mContext, this, hour, minute, DateFormat.is24HourFormat(getActivity()));
    }

    @Override
    public void onTimeSet(TimePicker view, int hourOfDay, int minute)
    {
        // when the time is selected, send it to the activity via its callback
        // interface method
        Calendar c = Calendar.getInstance();
        c.set(Calendar.HOUR_OF_DAY, hourOfDay);
        c.set(Calendar.MINUTE, minute);

        mListener.onTimePicked(c);
    }

    public static interface TimePickedListener
    {
        public void onTimePicked(Calendar time);
    }
}

Selecting time inside Main Fragment

public void selectTime(final TextView lblTime, final int position) {
    hideRight();
    timeFrag = TimePickerFragment.newInstance(getActivity(), new TimePickedListener() {@
        Override
        public void onTimePicked(Calendar time) {
            lblTime.setText(DateFormat.format("h:mm a", time));
        }
    }, now);
    timeFrag.show(getActivity().getSupportFragmentManager(), "timePicker");
}

07-02 17:28:04.214: E/XXX(10341): Uncaught exception is: 07-02 17:28:04.214: E/XXX(10341): java.lang.NullPointerException 07-02 17:28:04.214: E/XXX(10341): at com.common.TimePickerFragment.onTimeSet(TimePickerFragment.java:47) 07-02 17:28:04.214: E/XXX(10341): at android.app.TimePickerDialog.tryNotifyTimeSet(TimePickerDialog.java:130) 07-02 17:28:04.214: E/XXX(10341): at android.app.TimePickerDialog.onClick(TimePickerDialog.java:115) 07-02 17:28:04.214: E/XXX(10341): at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:166) 07-02 17:28:04.214: E/XXX(10341): at android.os.Handler.dispatchMessage(Handler.java:99) 07-02 17:28:04.214: E/XXX(10341): at android.os.Looper.loop(Looper.java:137) 07-02 17:28:04.214: E/XXX(10341): at android.app.ActivityThread.main(ActivityThread.java:4928) 07-02 17:28:04.214: E/XXX(10341): at java.lang.reflect.Method.invokeNative(Native Method) 07-02 17:28:04.214: E/XXX(10341): at java.lang.reflect.Method.invoke(Method.jav a:511) 07-02 17:28:04.214: E/XXX(10341): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791) 07-02 17:28:04.214: E/XXX(10341): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:558) 07-02 17:28:04.214: E/XXX(10341): at dalvik.system.NativeStart.main(Native Method)

Answer 1

You forget to initialize private TimePickedListener mListener;

Change your newInstance method with :

public static TimePickerFragment newInstance(Context context, TimePickedListener listener, Calendar now)
    {
        TimePickerFragment dialog = new TimePickerFragment();
        mContext = context;
        mListener = listener;
        hour = now.get(Calendar.HOUR_OF_DAY);
        minute = now.get(Calendar.MINUTE);

        return dialog;
    }

Answer 2

You didn't instantiate private TimePickedListener mListener; anywhere . It is referencing to null .

public static TimePickerFragment newInstance(Context context, TimePickedListener listener, Calendar now)
{
    TimePickerFragment dialog = new TimePickerFragment();
    mContext = context;
    hour = now.get(Calendar.HOUR_OF_DAY);
    minute = now.get(Calendar.MINUTE);
    mListener = listener; // you missed this line
    return dialog;
}