Question

I’ve a problem with a DatePickerDialog following steps from Android Tutorial.

Linking a TextView to launch a DatePickerDialog when gets focused as you can see below:

EditText fNac = (EditText)findViewById(R.id.regFecha);
            fNac.setonfocusChangeListener(new View.onfocusChangeListener(){

                    @Override
                    public void onfocusChange(View v, boolean hasFocus) {
                            // TODO Auto-generated method stub
                            // Desde aquí lanzamos el datepicker
                            if (hasFocus){
                                    DialogFragment newFragment = new DatePickerFragment();
                                    newFragment.show(getSupportFragmentManager() , "datePicker");
                            }
                    }

Works fine, the DatePickerDialog is launched. I instance a new DatePickerFragment class that is created in this way:

import java.util.Calendar;

import android.app.DatePickerDialog;
import android.app.Dialog;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;
import android.util.Log;
import android.widget.DatePicker;

public class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

    private DatePickerDialog mDatePickerDialog;

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState){
            // Usamos la fecha actual como primera fecha a mostrar
            final Calendar c = Calendar.getInstance();
            int year = c.get(Calendar.YEAR);
            int month = c.get(Calendar.MONTH);
            int day = c.get(Calendar.DAY_OF_MONTH);

            // Devolvemos la instancia de un Dialog con la fecha actual
            mDatePickerDialog = new DatePickerDialog(getActivity(),this,year,month,day);
            return mDatePickerDialog;
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int day) {
            // TODO Auto-generated method stub
            Log.v("LOG_CAT","OK");
    }

    public void onDateChanged(DatePicker view, int year, int monthOfYear,
                    int dayOfMonth) {
            // TODO Auto-generated method stub
            Log.v("LOG_CAT", "Ok2");
    }

}

And here is the problem. I want to change Dialog’s title using onDateChanged method, but it’s never called. I tried to create a onDateChangedListener but DatePickerDialog doesn’t have one.

How can i do this?

Thanks in advance.

Answer 1

Simply extend the DatePickerDialog class and override onDateChanged like below. I included a new constructor that accepts a Calendar object and sets the year, month and day itself, saving you the unnecessary typing. (I don’t understand why this isn’t an option already.) Anyway here is how to use the class and the shorter constructor:

public class DatePickerFragment extends DialogFragment implements OnDateSetListener {
    public class MyDatePickerDialog extends DatePickerDialog {
        private Calendar calendar;
        private final String format = "EEEE, MMMM dd, yyyy";

        // Regular constructor
        public MyDatePickerDialog(Context context, OnDateSetListener callBack, int year, int monthOfYear, int dayOfMonth) {
            super(context, callBack, year, monthOfYear, dayOfMonth);
            calendar = Calendar.getInstance();
        }

        // Short constructor
        public MyDatePickerDialog(Context context, OnDateSetListener callBack, Calendar calendar) {
            super(context, callBack, calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH), calendar.get(Calendar.DAY_OF_MONTH));
            this.calendar = calendar;
        }

        @Override
        public void onDateChanged(DatePicker view, int year, int month, int day) {
            super.onDateChanged(view, year, month, day);
            calendar.set(year, month, day);
            setTitle(DateFormat.format(format, calendar));
        }
    }

    private MyDatePickerDialog mDatePickerDialog;

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        mDatePickerDialog = new MyDatePickerDialog(this, this, Calendar.getInstance());
        return mDatePickerDialog;
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int day) {
        Log.v("DatePickerFragment", "onDateSet");
    }
}