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我能够从互联网上编译与共享首选项相关的项目，但我无法理解代码，甚至尝试阅读文档。你能举出在现实生活中看到 SharedPreferences 和 Editor 的例子吗？或者你能看到 SharedPreferences 与 Editor 的关系以及可以实现 SharedPreferences 的相关代码的任何场景吗？我想了解基础知识。谢谢。

            // Shared Preferences
            SharedPreferences pref;

            // Editor for Shared preferences
            Editor editor;

            public SessionManager(Context context){
                this._context = context;
                pref = _context.getSharedPreferences(PREF_NAME, PRIVATE_MODE);
                editor = pref.edit();
            }

                /**
         * Create login session
         * */
        public void createLoginSession(String name, String email){
            // Storing login value as TRUE
            editor.putBoolean(IS_LOGIN, true);

            // Storing name in pref
            editor.putString(KEY_NAME, name);

            // Storing email in pref
            editor.putString(KEY_EMAIL, email);

            // commit changes
            editor.commit();
        }   
/**
         * Check login method wil check user login status
         * If false it will redirect user to login page
         * Else won't do anything
         * */
        public void checkLogin(){
            // Check login status
            if(!this.isLoggedIn()){
                // user is not logged in redirect him to Login Activity
                Intent i = new Intent(_context, LoginActivity.class);
                // Closing all the Activities
                i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

                // Add new Flag to start new Activity
                i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

                // Staring Login Activity
                _context.startActivity(i);
            }

        }



        /**
         * Get stored session data
         * */
        public HashMap<String, String> getUserDetails(){
            HashMap<String, String> user = new HashMap<String, String>();
            // user name
            user.put(KEY_NAME, pref.getString(KEY_NAME, null));

            // user email id
            user.put(KEY_EMAIL, pref.getString(KEY_EMAIL, null));

            // return user
            return user;
        }

        /**
         * Clear session details
         * */
        public void logoutUser(){
            // Clearing all data from Shared Preferences
            editor.clear();
            editor.commit();

            // After logout redirect user to Loing Activity
            Intent i = new Intent(_context, LoginActivity.class);
            // Closing all the Activities
            i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

            // Add new Flag to start new Activity
            i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

            // Staring Login Activity
            _context.startActivity(i);
        }

        /**
         * Quick check for login
         * **/
        // Get Login State
        public boolean isLoggedIn(){
            return pref.getBoolean(IS_LOGIN, false);
        }
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1 回答 1

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来自开发者指南本身

The SharedPreferences class provides a general framework that allows you to save and retrieve persistent key-value pairs of primitive data types. You can use SharedPreferences to save any primitive data: booleans, floats, ints, longs, and strings. This data will persist across user sessions (even if your application is killed).

这基本上是一个 xml，它位于你的 data/data/"package name"/shared_prefs

目前它不支持多进程编辑/访问，但会满足您的目的。

您可以使用它来存储用户偏好，如背景颜色、文本颜色、通知音等

于 2013-05-31T03:59:53.220 回答