Android的阵列与GSON共享preferences [英] Android array to Sharedpreferences with Gson

问题描述

我需要创建的最后5个呼叫日期的数组。

I need to create an array of the last 5 call dates.

我知道我有救阵列上的日期，但我不知道如何重新安排其他记录保留这最后赎回日第一的纪录。始终保持只有5条记录

I know that I have to save the date on the array but I don't know how to reorder the other records to keep this last call date the 1st record. And always maintain only 5 records

目标是保存了最近一个电话串并添加到数组，在那之后我重新排序并保持只有5条记录，在那之后我用FlexJson做一个字符串，并保存在共享preferences。任何人有这个全过程的？

The Goal is to save that last call string and add to the array, after that I reorder to and maintain only the 5 records, after that I use FlexJson to make a string and save on sharedpreferences. Anyone have this full process?

在这里，我在做什么，但随处乱扔错误：

保存

SimpleDateFormat df = new SimpleDateFormat("HH:mm:ss dd-MM-yyyy", Locale.getDefault());
Calendar calendar = Calendar.getInstance();
String currentDateTimeString = df.format(calendar.getTime());

List<String> textList = new ArrayList<>();
JSONSerializer ser = new JSONSerializer();
textList.add(currentDateTimeString);

String jsonText = ser.deepSerialize(textList);

editor.putString("lastCall", jsonText);
editor.commit();

阅读：

String lastCall = callLogPreferences.getString("lastCall", null);
JSONDeserializer<List<String>> der = new JSONDeserializer<>();
List<String> textList = der.deserialize(lastCall);

我使用FlexJson我：<一href=\"http://stackoverflow.com/questions/20447897/gson-and-instancecreator-issue/20448172#20448172\">GSON和InstanceCreator问题

这不是从字符串转换为数组列表

It's not converting from string to Array List

推荐答案

首先，让我给你一个提醒 - 如果你有3提问创建3个主题，而不是一个与所有的问题。基于问题的标题为 Android的阵列共享preferences 我就这个问题给出一个答案

First let me give you an advise - if you have 3 question create 3 topics, not one with all the questions. Based on the question title: Android array to sharedpreferences I'll give an answer just to this issue.

所以，从你的问题，你要存储一个列表＆LT;弦乐＆GT; myList中在共享preferences 。要做到这一点，我建议你使用 GSON ，因为它很简单。其主要思想是序列化你的列表到字符串在 JSON 然后存储字符串：

So from your question you want to store a List<String> myList inside SharedPreferences. To do so I advise you to use Gson because it's simple. The main idea it's to serialize your List to a String in json and then store that String:

由于您使用的基本类型，你不必指定<一个href=\"http://stackoverflow.com/questions/14705860/saving-serializable-objects-list-into-shared$p$pferences/16607928#16607928\">TypeToken所以你只需要：

Since you are using primitive types you don't need to specify a TypeToken so you just need to:

public static final MY_LIST = "my_list";

List<String> myList = new ArrayList<String>();
SharedPreferences.Editor editor = prefs.edit();
editor.putString(MY_LIST, new Gson().toJson(myList));
editor.commit();

和它的存储。要检索列表只是做相反的：

And it's stored. To retrieve the list just do the opposite:

myList = new Gson().fromJson(prefs.getString(MY_LIST, null), List<String>);

这就是它！结果
希望它帮助。

And that's it!
Hope it helped.

PS：共享preferences 它用于可在其他类访问存储值 / 活动 /等或将持续重新启动应用程序之间的信息。你并不需要用它来完成你想要的：创建5有序的字符串列表

ps: SharedPreferences it's used to store values that can be accessed in other Classes/Activities/etc.. or to persist information between app restarts. You don't need this to accomplish what you want: Create a list with 5 ordered strings.

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