使用Facebook SDK时无法注销 - Android

我一直试图学习这个Facebook SDK几天了，我似乎陷入困境 . 我正在为学校项目构建一个基本应用程序，当用户登录第一时间时，Facebook允许您输入电子邮件和密码，然后它会让您登录 . 一旦用户单击“注销”，我就会退出 . . 据我所知 . 现在，当我返回点击登录时，它会自动重新登录到最后一个帐户 . 不给我一个切换帐户的选项 . 我怎样才能解决这个问题？

编辑***当我登录，然后注销，然后再次单击登录它说“您之前使用Facebook登录到”APP NAME“ . 您要继续吗？”

唯一的选择是取消和继续 . 我甚至无法尝试与另一个人签约！这是我的问题，如果有人能解决它会很棒！与此同时，我将继续尝试不同的事情

package example.com.demo_app;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;

import com.facebook.AccessToken;
import com.facebook.AccessTokenTracker;
import com.facebook.CallbackManager;
import com.facebook.FacebookActivity;
import com.facebook.FacebookCallback;
import com.facebook.FacebookException;
import com.facebook.FacebookSdk;
import com.facebook.GraphRequest;
import com.facebook.GraphResponse;
import com.facebook.appevents.AppEventsLogger;
import com.facebook.login.LoginBehavior;
import com.facebook.login.LoginManager;
import com.facebook.login.LoginResult;
import com.facebook.login.widget.LoginButton;
import com.facebook.login.widget.ProfilePictureView;

import org.json.JSONException;
import org.json.JSONObject;
import org.w3c.dom.Text;

public class MainActivity extends AppCompatActivity {

LoginButton fbButton;
CallbackManager callBackManager;

TextView nameBox;
TextView emailBox;
TextView idBox;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);



    fbButton = (LoginButton)findViewById(R.id.login_button);
    fbButton.setReadPermissions("email", "public_profile");

    callBackManager = CallbackManager.Factory.create();
    fbButton.registerCallback(callBackManager, new FacebookCallback<LoginResult>() {
        @Override
        public void onSuccess(LoginResult loginResult) {


            String user_id = loginResult.getAccessToken().getUserId();



            GraphRequest graphRequest = GraphRequest.newMeRequest(loginResult.getAccessToken(), new GraphRequest.GraphJSONObjectCallback() {
                @Override
                public void onCompleted(JSONObject object, GraphResponse response) {


                    if (object != null)
                    {
                        displayInfo(object);
                    }
                    else {
                        LoginManager.getInstance().logOut();

                    }
                }
            });

            Bundle parameters = new Bundle();
            parameters.putString("fields", "first_name, last_name, email, id");
            graphRequest.setParameters(parameters);
            graphRequest.executeAsync();


        }

        @Override
        public void onCancel() {


        }

        @Override
        public void onError(FacebookException error) {

        }
    });


}

public void displayInfo(JSONObject object)
{
    String first_name = "";
    String last_name = "";
    String email = "";
    String id = "";
    try {
        first_name = object.getString("first_name");
        last_name = object.getString("last_name");
        email = object.getString("email");
        id = object.getString("id");
    } catch (JSONException e) {
        e.printStackTrace();
    }

    nameBox = (TextView)findViewById(R.id.txtFullName);
    emailBox = (TextView)findViewById(R.id.txtEmail);
    idBox = (TextView)findViewById(R.id.txtID);

    nameBox.setText(first_name+ " " +last_name);
    emailBox.setText(email);
    idBox.setText(id);

    ProfilePictureView profilePictureView;

    profilePictureView = (ProfilePictureView) findViewById(R.id.friendProfilePicture);

    profilePictureView.setProfileId(id);



}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    callBackManager.onActivityResult(requestCode, resultCode, data);

}

}