Facebook登录后的重定向活动

我正在使用Android Facebook SDK(4.01)通过Facebook登录到我的应用程序.我的MainActivity上的Facebook登录成功，然后我使用Intent进行了下一个活动.那部分起作用.

I'm using Android Facebook SDK (4.01) to login to my app with Facebook. The facebook login from my MainActivity succeeds and then I use Intent to procced to next activity. That part works.

在那之后，在我的新活动(MainLobby)中，我希望能够通过按返回按钮从Facebook注销并返回到我以前的MainActivity.由于某些原因，当我按回MainLobby关闭时，它后面还有另一个MainLobby活动.因此，我必须按两次返回按钮才能返回MainActivity.为什么会这样?

After that in my new activity (MainLobby) I want to able to logout from facebook and return to my previous MainActivity, by pressing back button. For some reason when I press back the MainLobby closes, but has another MainLobby activity behind it. So I have to press back button twice to get back to MainActivity. Why is that?

主要活动类代码:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    FacebookSdk.sdkInitialize(getApplicationContext());
    setContentView(R.layout.main_activity);

    fbloginBT = (LoginButton) findViewById(R.id.fbloginBT);
    callback = CallbackManager.Factory.create();
    fbloginBT.registerCallback(callback, new FacebookCallback<LoginResult>() {
        @Override
        public void onSuccess(LoginResult loginResult) {
            System.out.println("onSuccess");
            Intent mainLobby = new Intent(MainActivity.this, MainLobby.class);
            startActivity(mainLobby);
        }

        @Override
        public void onCancel() {
            System.out.println("onCancel");
        }

        @Override
        public void onError(FacebookException e) {
            System.out.println("onError");
        }
    });
    fbloginBT.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            LoginManager.getInstance().logInWithReadPermissions(MainActivity.this, Arrays.asList("public_profile"));
        }
    });

}


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

主要大堂类代码:

@Override
public void onBackPressed() {
    if (mDrawerLayout.isDrawerOpen(Gravity.LEFT))
        mDrawerLayout.closeDrawer(Gravity.LEFT);
    else if (searchView.isShown() && !isClosed){
        searchView.onActionViewCollapsed();  //collapse your ActionView
        searchView.setQuery("", false);       //clears your query without submit
        isClosed = true;
    }
    else {
        LoginManager.getInstance().logOut();
        super.onBackPressed();
    }
}

更新:

我在Android Studio中的模拟器上正常工作.当我在Android手机设备上对其进行测试时，它的工作原理如上所述.

I works correct on emulator, in Android Studio. It works as described above when I test it on an Android phone device.