Stopping the DatePickerDialog from closing when use clicks the Set button

问题

I've implemented a DatePickerDialog using the example shown here.

In my implementation of the DatePickerDialog.OnDateSetListener I added validation logic to check that the selected date is within specific range.

private final DatePickerDialog.OnDateSetListener dateSetListener = new DatePickerDialog.OnDateSetListener() {

    @Override
    public void onDateSet(DatePicker view, int y, int m,
            int d) {

            final Calendar calendar = Calendar.getInstance();
            calendar.set(y, m, d);
            Date date = calendar.getTime();

      if(!myValidationFunction(date)) {
        // date not within allowed range
        // cancel closing of dialog ?
      }
    }
};

The problem I have is that the DatePickerDialog is closed automaticlly when the user clicks the set button and I want to keep the DatePickerDialog open if the validate rule fails.

Does anyone know how to stop the DatePickerDialog from closing when the user clicks the Set button?

回答1:

From API 11 the DatePicker can validate your date for you.

Following the guide you refer to, when overriding onCreateDialog, get DatePicker and set min and max date:

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // no changes from guide ...
    final DatePickerDialog dialog = new DatePickerDialog(getActivity(), this, year, month, day);
    dialog.getDatePicker().setMinDate(minDate);
    dialog.getDatePicker().setMaxDate(minDate);
    return dialog;
}

This way the user cannot pick a wrong date, thus no need to manually validate the date.

For older versions you can use a boolean for control when closing is allowed, and implement your own logic. Here I try to illustrate where you'll need to extend your code:

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final DatePickerDialog dialog = new DatePickerDialog(getActivity(), this, year, month, day){

            @Override
            public void onBackPressed() {
                allowClose = true;
                super.onBackPressed();
            }

            @Override
            public void onClick(DialogInterface dialog, int which) {
                if (which==DialogInterface.BUTTON_POSITIVE && validate()){
                    allowClose = true;
                }
                super.onClick(dialog, which);
            }

            @Override
            public void dismiss() {
                if (allowClose) {
                    super.dismiss();
                }
            }

        };

        return dialog;
    }

    private void onCancelBtnClick() {
        allowClose = true;
        dismiss();
    }

来源：https://stackoverflow.com/questions/9084585/stopping-the-datepickerdialog-from-closing-when-use-clicks-the-set-button