如何在 Android 上存储 HashMap? [英] How to store HashMap on Android?

问题描述

所以，我正在尝试在 Android 上存储 HashMap.我觉得用内部存储比较好，但是我不明白如何保存 HashMap在里面以后再看.有人可以解释一下如何正确地做到这一点吗?

So, I'm trying to store HashMap on Android. I think it's better to use internal storage, but I don't understand how to save HashMap in it and then read it later. Can someone explain how to do that properly, please?

有自己的名称和值的计数器.我想在某些活动开始时加载它们，使用它们(更改、删除、添加新的)，然后保存该数据以供下次使用.现在我使用 HashMap，因为它很容易删除/添加值.

There are counters with their own names and values. I want to load them onсe when some activity was started, work with them (change, delete, add new), and then save that data to use next time. Right now I use HashMap because it's easy to delete/add values.

HashMap<String, Integer> counters;

推荐答案

SharedPreferences 也将数据存储在 key-value 对中作为 hashmap，所以为什么不从 hashmap 中获取所有 key-value 并存储到 map 中，因为它:

SharedPreferences also store data in key-value pair as hashmap, so why not get all key-values from hashmap and store into map, as it:

SharedPreferences pref= getContext().getSharedPreferences("Your_Shared_Prefs"), 
                                                           Context.MODE_PRIVATE);
SharedPreferences.Editor editor= pref.edit();

    for (String s : map.keySet()) {
        editor.putString(s, map.get(s));
    }

要获取可以使用的值:

public abstract Map<String, ?> getAll ()

http://developer.android.com/reference/android/content/SharedPreferences.html#getAll%28%29

使用:

SharedPreferences pref= getContext().getSharedPreferences("Your_Shared_Prefs"), 
                                                           Context.MODE_PRIVATE);
HashMap<String, String> map= HashMap<String, String> pref.getAll();
for (String s : map.keySet()) {
        String value=map.get(s);
        //Use Value
    }

代码未编译，因此可能有一些小错误，但应该可以工作.

Code is not compiled, so it may have some minor errors, but should work.

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