public void facebookLogin()
    {
    	facebook = new Facebook("MYKEY");
    	sp = getPreferences(MODE_PRIVATE);
        String access_token = sp.getString("access_token", null);
        Long expires = sp.getLong("access_expires", 0);

        if (access_token != null){
            facebook.setAccessToken(access_token);
        }
        if (expires != 0){
            facebook.setAccessExpires(expires);
        }
        Log.d("MyTag", "token:" + facebook.getAccessToken());
        if(!facebook.isSessionValid())
        {
    	 facebook.authorize(this, new String[]{"publish_stream", "email"}, Facebook.FORCE_DIALOG_AUTH, new DialogListener() {

             public void onFacebookError(FacebookError e) {
                 Toast.makeText(getApplicationContext(), "onFacebookError", Toast.LENGTH_SHORT).show();
             }

             public void onError(DialogError e) {
                 Toast.makeText(getApplicationContext(), "onError", Toast.LENGTH_SHORT).show();
             }

             public void onComplete(Bundle values) {

                 Editor editor = sp.edit();
                 Log.d("MyTag", "token:" + facebook.getAccessToken());
                 editor.putString("access_token", facebook.getAccessToken());
                 editor.putLong("access_expires", facebook.getAccessExpires());
                 editor.commit();

             }

             public void onCancel() {
                 // TODO Auto-generated method stub

             }


         });
        }