Java 如果以前使用android studio登录应用程序

好吧，我对android studio和java有点陌生 我正在尝试一个活动，检查用户以前是否通过登录选项、谷歌或facebook登录 如果他们是我希望他们被重定向到用户页面 如果它们不是，我希望它们被重定向到登录/注册页面

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

这就是我的mainActivity.java文件的样子

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

    //see if the person is logged in by getting their preference
    SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);

    //Get the value for the counter
    int counter = app_preferences.getInt("counter, 0");


    else
    {
        // condition false take it user on login form
    }


}

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

}

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

//如果此人未登录，请转到欢迎页面 //如果用户已登录，请转到主页

---

我尝试过使用youtube，但没有得到任何信息

我建议阅读facebook开发者页面，该页面提供了一个关于在Android应用程序中集成facebook登录的不错教程：

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

---

您可以在SharedPreference存储一个布尔值，然后如下设置：

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

当用户使用facebook、twitter成功登录时。。等等

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

这样做：

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
int defaultValue = false;
boolean loggedIn = sharedPref.getBoolean(getString(R.string.save_log_in_state), defaultValue);

当应用程序决定显示登录/注册活动或用户已登录时，您可以在5秒左右的时间内使用启动屏幕加载

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();

---

共享首选项参考：

您是否尝试过Facebook开发者教程：甚至Android Hive:，做一些研究。

// Some where when the app first installed    
boolean loggedIn = false;

SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putInt(getString(R.string.save_log_in_state), loggedIn);
editor.commit();