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DatePicker.OnDateChangedListener called twice

I'm trying to create an app where the user selects a date from a DatePicker, and then a list is updated with some values.

My GUI looks like this:

    <LinearLayout
    android:id="@+id/linearLayout1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center" >


    <DatePicker
        android:id="@+id/datePicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

<LinearLayout
    android:id="@+id/linearLayout2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >



   <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1" >


    </ListView> 
</LinearLayout>

Whereas my DatePicker initialization and handling look as follows:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.main);

    datePicker = (DatePicker) findViewById(R.id.datePicker);

    Calendar c = Calendar.getInstance();

    year = c.get(Calendar.YEAR);
    month = c.get(Calendar.MONTH);
    day = c.get(Calendar.DAY_OF_MONTH);

    datePicker.init(year, month, day, dateSetListener);
}

private DatePicker.OnDateChangedListener dateSetListener = new DatePicker.OnDateChangedListener() {

    public void onDateChanged(DatePicker view, int year, int monthOfYear,
            int dayOfMonth) {
         Calendar c = Calendar.getInstance();
         c.set(year, monthOfYear, dayOfMonth);
         System.out.println ("TEST");

    }
};

In CatLog I see that "TEST" string is output twice, each time I play with the +/- buttons on the widget. What could be the problem?

Note: I've "disabled" the list-updating code on purpose, in order to make sure that the problem is not related to the ListView, as in here

like image 653
tomor Avatar asked Sep 15 '12 09:09

tomor


3 Answers

When I test my application, method onDateSet called twice after accept the date selection and once when I canceled.

I added a validation in the method onDateSet with parameter view, something like this

@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth){
    if (view.isShown()) {
        updateDate(year, monthOfYear, dayOfMonth);
    }
}

I hope you serve

like image 94
Cesardl Avatar answered Nov 10 '22 23:11

Cesardl


I still haven't managed to find a neat fix. I've rather found a workaround, so the event does not fire twice. The workaround is as follows:

int timesCalled = 1;

private DatePicker.OnDateChangedListener dateSetListener = new DatePicker.OnDateChangedListener() {

public void onDateChanged(DatePicker view, int year, int monthOfYear,
        int dayOfMonth) {
     Calendar c = Calendar.getInstance();
     c.set(year, monthOfYear, dayOfMonth);
     timesCalled += 1;

     if ((timesCalled % 2) == 0) {
        System.out.println ("TEST");
     }

}};
like image 28
tomor Avatar answered Nov 11 '22 00:11

tomor


Instead of the onDateSet callback I've overridden onClick method of the DatePickerDialog dialog and handle BUTTON_POSITIVE clicks only.

public static class DatePickerFragment extends DialogFragment {
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final Calendar c = Calendar.getInstance();
        int initialYear = c.get(Calendar.YEAR);
        int initialMonth = c.get(Calendar.MONTH);
        int initialDay = c.get(Calendar.DAY_OF_MONTH);
        return new DatePickerDialog(getActivity(), null, initialYear, initialMonth, initialDay) {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                if (which == BUTTON_POSITIVE) {
                    int year = getDatePicker().getYear();
                    int month = getDatePicker().getMonth();
                    int day = getDatePicker().getDayOfMonth();

                    //TODO: Do your logic here
                }
                super.onClick(dialog, which);
            }
        };
    }
}

The code stays clear but still it's not clear why onDateSet is called twice.

like image 2
evgeny.myasishchev Avatar answered Nov 11 '22 01:11

evgeny.myasishchev