Устаревший метод showDialog() в DatePickerDialog

package com.samples.datepickerdialog;
 
import java.util.Calendar;
 
import android.app.Activity;
import android.app.DatePickerDialog;
import android.app.Dialog;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TextView;
 
public class MainActivity extends Activity {
private TextView mDateDisplay;
private Button mButton;
private int mYear;
private int mMonth;
private int mDay;
static final int IDD_DATE = 0;
 
 
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
 
mDateDisplay = (TextView)findViewById(R.id.text);
mButton = (Button)findViewById(R.id.button);
 
mButton.setOnClickListener(new View.OnClickListener() {
 
@Override
public void onClick(View v) {
showDialog(IDD_DATE);
 
}
});
 
final Calendar c = Calendar.getInstance();
mYear = c.get(Calendar.YEAR);
mMonth = c.get(Calendar.MONTH);
mDay = c.get(Calendar.DAY_OF_YEAR);
updateDisplay();
}
 
protected Dialog onCreateDialog(int id){
switch(id) {
case IDD_DATE:
return new DatePickerDialog(this, mDateSetListener, mYear, mMonth, mDay);
}
return null;
}
 
private void updateDisplay(){
mDateDisplay.setText(new StringBuilder()
.append(mMonth+1).append("-")
.append(mDay).append("-")
.append(mYear).append("-"));
}
 
private DatePickerDialog.OnDateSetListener mDateSetListener
= new DatePickerDialog.OnDateSetListener() {
 
@Override
public void onDateSet(DatePicker view, int year, int monthOfYear,
int dayOfMonth) {
mYear = year;
mMonth = monthOfYear;
mDay = dayOfMonth;
updateDisplay();
 
}
};
 
 
}

AlertDialog.Builder builder = new AlertDialog.Builder(
                    MainActivity.this);
 
            builder.setMessage("")
 
            .setTitle("")
 
            .setPositiveButton("", new DialogInterface.OnClickListener() {
 
                public void onClick(DialogInterface dialog, int id) {
 
                    finish();
 
                    dialog.dismiss();
 
                }
 
            })
 
            .setNegativeButton("", new DialogInterface.OnClickListener() {
 
                public void onClick(DialogInterface dialog, int which) {
 
                    dialog.dismiss();
 
                }
 
            });
 
            AlertDialog alert = builder.create();
 
            alert.show();
 
            return true;
 
        }