Android - กด Item ใน Listview แล้วเด้ง Dialog มีแต่ ok ถ้าจะเพิ่ม Cancel ต้องทำยังไง

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Check-in")
    .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            //blah blah.
        }
    })
    .setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int id) {
            dialog.dismiss();
        }
    });

builder.create();
builder.show();

builder.setNegativeButton("Cancel", null);