使用delegate Kotlin，我们可以轻松地从共享首选项中放置和获取数据。

    inline fun <reified T> Context.sharedPrefs(key: String) = object : ReadWriteProperty<Any?, T> {

        val sharedPrefs by lazy { this@sharedPrefs.getSharedPreferences("APP_DATA", Context.MODE_PRIVATE) }
        val gson by lazy { Gson() }
        var newData: T = (T::class.java).newInstance()

        override fun getValue(thisRef: Any?, property: KProperty<*>): T {
            return getPrefs()
        }

        override fun setValue(thisRef: Any?, property: KProperty<*>, value: T) {
            this.newData = value
            putPrefs(newData)
        }

        fun putPrefs(value: T?) {
            sharedPrefs.edit {
                when (value) {
                    is Int -> putInt(key, value)
                    is Boolean -> putBoolean(key, value)
                    is String -> putString(key, value)
                    is Long -> putLong(key, value)
                    is Float -> putFloat(key, value)
                    is Parcelable -> putString(key, gson.toJson(value))
                    else          -> throw Throwable("no such type exist to put data")
                }
            }
        }

        fun getPrefs(): T {
            return when (newData) {
                       is Int -> sharedPrefs.getInt(key, 0) as T
                       is Boolean -> sharedPrefs.getBoolean(key, false) as T
                       is String -> sharedPrefs.getString(key, "") as T ?: "" as T
                       is Long -> sharedPrefs.getLong(key, 0L) as T
                       is Float -> sharedPrefs.getFloat(key, 0.0f) as T
                       is Parcelable -> gson.fromJson(sharedPrefs.getString(key, "") ?: "", T::class.java)
                       else          -> throw Throwable("no such type exist to put data")
                   } ?: newData
        }

    }

    //use this delegation in activity and fragment in following way
        var ourData by sharedPrefs<String>("otherDatas")

另一种不使用Json格式保存和恢复android sharedpreferences对象的方法

private static ExampleObject getObject(Context c,String db_name){
            SharedPreferences sharedPreferences = c.getSharedPreferences(db_name, Context.MODE_PRIVATE);
            ExampleObject o = new ExampleObject();
            Field[] fields = o.getClass().getFields();
            try {
                for (Field field : fields) {
                    Class<?> type = field.getType();
                    try {
                        final String name = field.getName();
                        if (type == Character.TYPE || type.equals(String.class)) {
                            field.set(o,sharedPreferences.getString(name, ""));
                        } else if (type.equals(int.class) || type.equals(Short.class))
                            field.setInt(o,sharedPreferences.getInt(name, 0));
                        else if (type.equals(double.class))
                            field.setDouble(o,sharedPreferences.getFloat(name, 0));
                        else if (type.equals(float.class))
                            field.setFloat(o,sharedPreferences.getFloat(name, 0));
                        else if (type.equals(long.class))
                            field.setLong(o,sharedPreferences.getLong(name, 0));
                        else if (type.equals(Boolean.class))
                            field.setBoolean(o,sharedPreferences.getBoolean(name, false));
                        else if (type.equals(UUID.class))
                            field.set(
                                    o,
                                    UUID.fromString(
                                            sharedPreferences.getString(
                                                    name,
                                                    UUID.nameUUIDFromBytes("".getBytes()).toString()
                                            )
                                    )
                            );

                    } catch (IllegalAccessException e) {
                        Log.e(StaticConfig.app_name, "IllegalAccessException", e);
                    } catch (IllegalArgumentException e) {
                        Log.e(StaticConfig.app_name, "IllegalArgumentException", e);
                    }
                }
            } catch (Exception e) {
                System.out.println("Exception: " + e);
            }
            return o;
        }
        private static void setObject(Context context, Object o, String db_name) {
            Field[] fields = o.getClass().getFields();
            SharedPreferences sp = context.getSharedPreferences(db_name, Context.MODE_PRIVATE);
            SharedPreferences.Editor editor = sp.edit();
            for (Field field : fields) {
                Class<?> type = field.getType();
                try {
                    final String name = field.getName();
                    if (type == Character.TYPE || type.equals(String.class)) {
                        Object value = field.get(o);
                        if (value != null)
                            editor.putString(name, value.toString());
                    } else if (type.equals(int.class) || type.equals(Short.class))
                        editor.putInt(name, field.getInt(o));
                    else if (type.equals(double.class))
                        editor.putFloat(name, (float) field.getDouble(o));
                    else if (type.equals(float.class))
                        editor.putFloat(name, field.getFloat(o));
                    else if (type.equals(long.class))
                        editor.putLong(name, field.getLong(o));
                    else if (type.equals(Boolean.class))
                        editor.putBoolean(name, field.getBoolean(o));
                    else if (type.equals(UUID.class))
                        editor.putString(name, field.get(o).toString());

                } catch (IllegalAccessException e) {
                    Log.e(StaticConfig.app_name, "IllegalAccessException", e);
                } catch (IllegalArgumentException e) {
                    Log.e(StaticConfig.app_name, "IllegalArgumentException", e);
                }
            }

            editor.apply();
        }

将数据存储在SharedPreference中

SharedPreferences mprefs = getSharedPreferences(AppConstant.PREFS_NAME, MODE_PRIVATE)
mprefs.edit().putString(AppConstant.USER_ID, resUserID).apply();

我在使用已接受的答案访问跨活动的共享首选项数据时遇到了麻烦。在这些步骤中，您将为getSharedPreferences提供一个名称以访问它。

在构建中添加以下依赖项。Gradle脚本下的gradel (Module: app)文件:

implementation 'com.google.code.gson:gson:2.8.5'

保存:

MyObject myObject = new MyObject;
//set variables of 'myObject', etc.

SharedPreferences mPrefs = getSharedPreferences("Name", Context.MODE_PRIVATE);

Editor prefsEditor = mPrefs.edit();
Gson gson = new Gson();
String json = gson.toJson(myObject);
prefsEditor.putString("Key", json);
prefsEditor.commit();

在不同的活动中检索:

SharedPreferences mPrefs = getSharedPreferences("Name", Context.MODE_PRIVATE);

Gson gson = new Gson();
String json = mPrefs.getString("Key", "");
MyObject obj = gson.fromJson(json, MyObject.class);

如果你的对象很复杂，我建议序列化/XML/JSON，并将这些内容保存到SD卡。你可以在这里找到关于如何保存到外部存储的其他信息: http://developer.android.com/guide/topics/data/data-storage.html#filesExternal

我的utils类保存列表到SharedPreferences

public class SharedPrefApi {
    private SharedPreferences sharedPreferences;
    private Gson gson;

    public SharedPrefApi(Context context, Gson gson) {
        this.sharedPreferences = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);
        this.gson = gson;
    } 

    ...

    public <T> void putObject(String key, T value) {
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putString(key, gson.toJson(value));
        editor.apply();
    }

    public <T> T getObject(String key, Class<T> clazz) {
        return gson.fromJson(getString(key, null), clazz);
    }
}

使用

// for save
sharedPrefApi.putList(SharedPrefApi.Key.USER_LIST, userList);

// for retrieve
List<User> userList = sharedPrefApi.getList(SharedPrefApi.Key.USER_LIST, User.class);

． 我的utils的完整代码//检查使用实例的活动代码