安卓dialog复选框怎么获取勾选的数据？

  private void fuXuanKuang() {
    final String[] items = { "Item1", "Item2" };
    AlertDialog.Builder builder = new Builder(MainActivity.this);
    builder.setIcon(android.R.drawable.ic_dialog_info);
    builder.setTitle("复选框");
    builder.setMultiChoiceItems(items, new boolean[] { true, false },
            new OnMultiChoiceClickListener() {

                @Override
                public void onClick(DialogInterface dialog, int which,
                        boolean isChecked) {
                    if (isChecked) {

                    }
                }
            });
    builder.setPositiveButton("确认", new OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {
            Toast.makeText(MainActivity.this, "", Toast.LENGTH_SHORT)
                    .show();
        }
    });
    builder.setNegativeButton("取消", null);

    Dialog dialog = builder.create();
    dialog.show();
}