Facebook Graphs API返回会话无效

Question

我想在我的Android应用中使用Facebook Graph API。我试图看看我是否可以使用never expires的访问令牌登录Facebook，但我的代码总是返回Session is Invalid。有人能告诉我在下面的代码中我做错了什么吗？感谢

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;

import com.facebook.AccessToken;
import com.facebook.android.Facebook;

public class MainActivity extends Activity {
    Facebook fb;

    @SuppressWarnings("deprecation")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        fb = new Facebook(getString(R.string.APP_ID));
        fb.setAccessToken(getString(R.string.ACCESS_TOKEN));
        //Expiry is set to 0, since the token never expires
        fb.setAccessExpires(0);



        if (fb.isSessionValid()) {

            Toast.makeText(this, "Session is valid",
                    android.widget.Toast.LENGTH_LONG).show();
            Log.d("TAG2", getString(R.string.ACCESS_TOKEN));

        } else
            Toast.makeText(this,
                    "Session is Invalid"+ getString(R.string.ACCESS_TOKEN),
                    android.widget.Toast.LENGTH_LONG).show();
            Log.d("TAG3", getString(R.string.ACCESS_TOKEN));


    }

}