在SharedPreferences中存储Model的数组列表

Add this dependency implementation 'com.google.code.gson:gson:2.8.8' Then after you convert your Model Class into JSON using Gson. Gson gson = new Gson(); String json = gson.toJson(chModelArrayList); //here chModelArrayList is a ArrayList<Model> of Model Class Then after you can add this string to SharedPreferences SharedPreferences preferences; //Create Object of SharedPreferences SharedPreferences.Editor editor; //Create Object of SharedPreferences.Editor //initialize SharedPreferences preferences = activity.getPreferences(Context.MODE_PRIVATE); editor = preferences.edit(); //Add-In SharedPreferences editor.putString(key, json); editor.commit(); for your list from SharedPreferences String json = preferences.getString(key, defVal); Gson gson = new Gson(); //Pass Your Model ArrayList in TypeToken Type type = new TypeToken<ArrayList<ChModel>>() {}.getType(); //here you get your list ArrayList<ChModel> switchGroup1 = gson.fromJson(json, type);

您可以使用以下代码存储类对象，并从共享首选项检索任何对象。

将以下依赖项添加到应用gradle中

dependencies {
 implementation 'com.google.code.gson:gson:2.8.6'
 //Other dependencies of our project
} 

在共享pref文件中添加以下代码。

 /**
 * Saves object into the Preferences.
 *
 * @param `object` Object of model class (of type [T]) to save
 * @param key Key with which Shared preferences to
 **/
fun <T> put(`object`: T, key: String) {
    //Convert object to JSON String.
    val jsonString = GsonBuilder().create().toJson(`object`)
    //Save that String in SharedPreferences
    preferences.edit().putString(key, jsonString).apply()
}

/**
 * Used to retrieve object from the Preferences.
 *
 * @param key Shared Preference key with which object was saved.
 **/
inline fun <reified T> get(key: String): T? {
    //We read JSON String which was saved.
    val value = preferences.getString(key, null)
    //JSON String was found which means object can be read.
    //We convert this JSON String to model object. Parameter "c" (of
    //type Class < T >" is used to cast.
    return GsonBuilder().create().fromJson(value, T::class.java)
}
}

要添加到@MuhammadAamirALi的答案，您可以使用Gson保存和检索对象列表

保存用户定义对象的列表到SharedPreferences

public static final String KEY_CONNECTIONS = "KEY_CONNECTIONS";
SharedPreferences.Editor editor = getPreferences(MODE_PRIVATE).edit();

User entity = new User();
// ... set entity fields

List<Connection> connections = entity.getConnections();
// convert java object to JSON format,
// and returned as JSON formatted string
String connectionsJSONString = new Gson().toJson(connections);
editor.putString(KEY_CONNECTIONS, connectionsJSONString);
editor.commit();

从SharedPreferences获取用户定义对象的列表

String connectionsJSONString = getPreferences(MODE_PRIVATE).getString(KEY_CONNECTIONS, null);
Type type = new TypeToken < List < Connection >> () {}.getType();
List < Connection > connections = new Gson().fromJson(connectionsJSONString, type);

您可以使用gson.jar将类对象存储到SharedPreferences中。 你可以从google-gson下载这个罐子

或者在Gradle文件中添加GSON依赖项:

implementation 'com.google.code.gson:gson:2.8.8'

你可以在这里找到最新的版本

创建共享首选项:

SharedPreferences  mPrefs = getPreferences(MODE_PRIVATE);

保存:

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

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

检索:

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

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")

我已经使用jackson来存储我的对象(jackson)。

添加杰克逊库到gradle:

api 'com.fasterxml.jackson.core:jackson-core:2.9.4'
api 'com.fasterxml.jackson.core:jackson-annotations:2.9.4'
api 'com.fasterxml.jackson.core:jackson-databind:2.9.4'

我的测试类:

public class Car {
    private String color;
    private String type;
    // standard getters setters
}

Java对象转换为JSON:

ObjectMapper objectMapper = new ObjectMapper();
String carAsString = objectMapper.writeValueAsString(car);

存储在共享首选项中:

preferences.edit().car().put(carAsString).apply();

从共享首选项中恢复:

ObjectMapper objectMapper = new ObjectMapper();
Car car = objectMapper.readValue(preferences.car().get(), Car.class);