How to get OnClick in DatePickerDialog.OnDateSetListener?

Question

I am using the following method to pop up the dialog to pick the date.

private DatePickerDialog.OnDateSetListener mDateSetListener =
        new DatePickerDi         


        

Answer 1

If you don't want to use a custom implementation of such dialog, you have to subclass DatePickerDialog to achieve such behavior. You can't block the dialog from closing just with DatePickerDialog.OnDateSetListener.

Unfortunatelly, implementations of the dialog vary with different API levels, so it's not that trivial to get the desired behavior with subclassing. You need to add some hacks to make it work reliably.

I've created a sample implementation that blocks the dialog from closing unless an appropriate date is set (or a cancel or back button is hit). Adjust it to display your alert to the users, the best place is the else branch in onClick() method.

class CheckingDatePickerDialog extends DatePickerDialog {

    private int year;
    private boolean cancel = false;
    private boolean isCancelable = true;

    CheckingDatePickerDialog(Context context, OnDateSetListener callBack, int year, int monthOfYear, int dayOfMonth) {
        super(context, callBack, year, monthOfYear, dayOfMonth);
        this.year = year;
    }

    CheckingDatePickerDialog(Context context, int theme, OnDateSetListener callBack, int year, int monthOfYear, int dayOfMonth) {
        super(context, theme, callBack, year, monthOfYear, dayOfMonth);
        this.year = year;
    }


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // allow closing the dialog with cancel button
        Button btn = getButton(BUTTON_NEGATIVE);
        if (btn != null) {
            btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    cancel = true;
                    dismiss();
                }
            });
        }
    }

    @Override
    public void setCancelable(boolean flag) {
        isCancelable = false;
        super.setCancelable(flag);
    }

    @Override
    public void onBackPressed() {
        // allow closing the dialog with back button if the dialog is cancelable
        cancel = isCancelable;
        super.onBackPressed();
    }

    private boolean isOldEnough() {
        // test if the date is allowed
        return year <= 1994;
    }

    @Override
    public void onClick(DialogInterface dialog, int which) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            // necessary for some Honeycomb devices
            DatePicker dp = getDatePicker();
            this.year = dp.getYear();
        }

        if (isOldEnough()) {
            // OnDateSetListener is called in super.onClick()
            super.onClick(dialog, which);  
        } else {
            // place your alert here
        }
    }

    @Override
    public void onDateChanged(DatePicker view, int year, int month, int day) {
        // on some Honeycomb devices called only with the first change
        // necessary for devices running Android 2.x
        this.year = year;
        super.onDateChanged(view, year, month, day);
    }

    @Override
    public void dismiss() {
        if (cancel || isOldEnough()) {
            // do not allow the dialog to be dismissed unless a cancel or back button was clicked
            super.dismiss();
        }
    }
};