Custom DialogFragment in Preferences

gistfile1.txt

    public static class MyPasswordInputDialog extends DialogFragment {
        private SharedPreferences mPref;
            private EditText mPasswd1;
            private EditText mPasswd2;

            @Override
            public Dialog onCreateDialog(Bundle savedInstanceState) {
                mPref = PreferenceManager.getDefaultSharedPreferences(MyPasswordInputDialog.this.getActivity());
                AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

                LayoutInflater factory = LayoutInflater.from(getActivity());
                final View inputView = factory.inflate(R.layout.password_input_layout, null);

                mPasswd1 = (EditText)inputView.findViewById(R.id.passwd1);
                mPasswd2 = (EditText)inputView.findViewById(R.id.passwd2);

                builder.setView(inputView);
                builder.setMessage(getResources().getString(R.string.password_input_tile));

                builder.setPositiveButton(getResources().getString(R.string.positive_button_string), 
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int whichButton) {
                            // no implementation
                        }
                    });

                builder.setNegativeButton(getResources().getString(R.string.negative_button_string), 
                    new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            // no implementation
                        }
                    });
                builder.setCancelable(true);

                AlertDialog dialog = builder.create();

                dialog.setOnShowListener(new OnShowListener() {

                    @Override
                    public void onShow(DialogInterface dialog) {
                        final DialogInterface d = dialog;
                        Button buttonOK = ((AlertDialog)dialog).getButton( DialogInterface.BUTTON_POSITIVE );
                        buttonOK.setOnClickListener(new OnClickListener() {

                            @Override
                            public void onClick(View arg0) {
                                if (passwdInputCheck()) {
                                    d.dismiss();
                                }
                            }
                        });
                    }
                });

                return dialog;
            }

            private boolean passwdInputCheck() {
                String passwd1 = mPasswd1.getText().toString();
                String passwd2 = mPasswd2.getText().toString();

                if (passwd1.equals("") {
                    Toast.makeText(getActivity(), 
                        getActivity().getResources().getString(R.string.toast_password_column_error), 
                        Toast.LENGTH_LONG).show();
                    return false;
                }
			
                if (!passwd1.equals(passwd2)) {
                    Toast.makeText(getActivity(), 
                        getActivity().getResources().getString(R.string.toast_password_input_error), 
                        Toast.LENGTH_LONG).show();
                    return false;
                }

                Editor e = mPref.edit();
                e.putString("password", passwd1);
                e.commit();

                return true;
            }
        }