blocks|key|32624|text|您当前有两个选项|type|unstyled|depth|inlineStyleRanges|entityRanges|data|32625|a)使用SharedPreferences|32626|b)使用SQLite并保存其中的值。|32627|如何执行|32628|a)+SharedPreferences|32629|首先将列表存储为集合，然后在从SharedPreferences读取时将其转换回列表。|32630|Listtasks+=+new+ArrayList<String>();
Set<String>+tasksSet+=+new+HashSet<String>(Listtasks);
PreferenceManager.getDefaultSharedPreferences(context)
++++.edit()
++++.putStringSet("tasks_set",+tasksSet)
++++.commit();|code-block|syntax|javascript|32631|然后当你读到它的时候：|32632|Set<String>+tasksSet+=+PreferenceManager.getDefaultSharedPreferences(context)
++++.getStringSet("tasks_set",+new+HashSet<String>());
List<String>+tasksList+=+new+ArrayList<String>(tasksSet);|32633|b)+SQLite一个好的教程：http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/|offset|length|32634|entityMap|0|LINK|mutability|MUTABLE|url|http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/^0|0|0|0|0|0|0|0|0|0|G|1X|0|0^^$0|@$1|2|3|4|5|6|7|16|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|17|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|18|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|19|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|1A|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|1B|8|@]|9|@]|A|$]]|$1|L|3|M|5|N|7|1C|8|@]|9|@]|A|$O|P]]|$1|Q|3|R|5|6|7|1D|8|@]|9|@]|A|$]]|$1|S|3|T|5|N|7|1E|8|@]|9|@]|A|$O|P]]|$1|U|3|V|5|6|7|1F|8|@]|9|@$W|1G|X|1H|1|1I]]|A|$]]|$1|Y|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]]|Z|$10|$5|11|12|13|A|$14|15]]]]

You currently have two options 
a) Use SharedPreferences 
b) Use SQLite and save values in that.

How to perform 
a) SharedPreferences 
First store your List as a Set, and then convert it back to a List when you read from SharedPreferences. 

<pre><code>Listtasks = new ArrayList&lt;String&gt;();
Set&lt;String&gt; tasksSet = new HashSet&lt;String&gt;(Listtasks);
PreferenceManager.getDefaultSharedPreferences(context)
 .edit()
 .putStringSet("tasks_set", tasksSet)
 .commit();
</code></pre>

Then when you read it:

<pre><code>Set&lt;String&gt; tasksSet = PreferenceManager.getDefaultSharedPreferences(context)
 .getStringSet("tasks_set", new HashSet&lt;String&gt;());
List&lt;String&gt; tasksList = new ArrayList&lt;String&gt;(tasksSet);
</code></pre>

b) SQLite
A good tutorial: <a href="http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/" rel="nofollow">http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/</a>

blocks|key|4540229|text|在SharedPreferences中，您只能存储原语。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4540230|一种可能的方法是使用GSON并将值存储到JSON中的首选项中。|4540231|Gson+gson+=+new+Gson();
String+json+=+gson.toJson(medicineList);

yourPrefereces.putString("listOfProducts",+json);
yourPrefereces.commit();|code-block|syntax|javascript|4540232|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

In SharedPreferences you can store only primitives.

As one possible approach is that you can use GSON and store values into preferences in JSON.

<pre><code>Gson gson = new Gson();
String json = gson.toJson(medicineList);

yourPrefereces.putString("listOfProducts", json);
yourPrefereces.commit();
</code></pre>

blocks|key|32684|text|只能使用原语类型，因为首选项保存在内存中。但是你可以使用Gson将你的类型序列化为json，并将字符串放入首选项中：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|32685|private+static+SharedPreferences+sharedPreferences+=+context.getSharedPreferences(STORE_FILE_NAME,+Context.MODE_PRIVATE);

private+static+SharedPreferences.Editor+editor+=+sharedPreferences.edit();
++++
public+<T>+void+setList(String+key,+List<T>+list)+{
++++Gson+gson+=+new+Gson();
++++String+json+=+gson.toJson(list);
++++
++++set(key,+json);
}

public+static+void+set(String+key,+String+value)+{
++++editor.putString(key,+value);
++++editor.commit();
}|code-block|syntax|javascript|32686|​|32687|来自@StevenTB的以下评论中的额外镜头|32688|检索|32689|+public+List<YourModel>+getList(){
++++List<YourModel>+arrayItems;
++++String+serializedObject+=+sharedPreferences.getString(KEY_PREFS,+null);+
++++if+(serializedObject+!=+null)+{
+++++++++Gson+gson+=+new+Gson();
+++++++++Type+type+=+new+TypeToken<List<YourModel>>(){}.getType();
+++++++++arrayItems+=+gson.fromJson(serializedObject,+type);
+++++}
}|32690|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

It only possible to use primitive types because preference keep in memory. But what you can use is serialize your types with Gson into json and put string into preferences:
<pre><code>private static SharedPreferences sharedPreferences = context.getSharedPreferences(STORE_FILE_NAME, Context.MODE_PRIVATE);

private static SharedPreferences.Editor editor = sharedPreferences.edit();
 
public &lt;T&gt; void setList(String key, List&lt;T&gt; list) {
 Gson gson = new Gson();
 String json = gson.toJson(list);
 
 set(key, json);
}

public static void set(String key, String value) {
 editor.putString(key, value);
 editor.commit();
}
</code></pre>
 
Extra Shot from below comment by @StevenTB
To Retrive
<pre><code> public List&lt;YourModel&gt; getList(){
 List&lt;YourModel&gt; arrayItems;
 String serializedObject = sharedPreferences.getString(KEY_PREFS, null); 
 if (serializedObject != null) {
 Gson gson = new Gson();
 Type type = new TypeToken&lt;List&lt;YourModel&gt;&gt;(){}.getType();
 arrayItems = gson.fromJson(serializedObject, type);
 }
}
</code></pre>

blocks|key|4540294|text|所有与JSON相关的答案都是可以的，但请记住，如果实现了java.io.Serializable接口，Java允许序列化任何对象。这样，您也可以将其作为序列化对象保存到preferences中。下面是一个存储为首选项的示例：https://gist.github.com/walterpalladino/4f5509cbc8fc3ecf1497f05e37675111我希望这可以作为一种选择来帮助你。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4540295|entityMap|0|LINK|mutability|MUTABLE|url|https://gist.github.com/walterpalladino/4f5509cbc8fc3ecf1497f05e37675111^0|34|20|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

All the answer related to JSON are Ok but remember Java allows you to serialize any object if you implement the java.io.Serializable interface.
This way you can save it to preferences as a serialized object too.
Here is an example for storing as Preferences: <a href="https://gist.github.com/walterpalladino/4f5509cbc8fc3ecf1497f05e37675111" rel="nofollow noreferrer">https://gist.github.com/walterpalladino/4f5509cbc8fc3ecf1497f05e37675111</a>
I hope this could help you as an option.

blocks|key|33041|text|SharedPreferences+mPrefs+=+getPreferences(MODE_PRIVATE);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|33042|为了保存|unstyled|33043|Editor+prefsEditor+=+mPrefs.edit();
Gson+gson+=+new+Gson();
String+json+=+gson.toJson(myObject);
prefsEditor.putString("MyObject",+json);
prefsEditor.commit();|33044|For+get|33045|Gson+gson+=+new+Gson();
String+json+=+mPrefs.getString("MyObject",+"");
MyObject+obj+=+gson.fromJson(json,+MyObject.class);|33046|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|P|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$B|C]]|$1|I|3|J|5|F|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$B|C]]|$1|M|3|-4|5|F|7|T|8|@]|9|@]|A|$]]]|N|$]]

<pre><code>SharedPreferences mPrefs = getPreferences(MODE_PRIVATE);
</code></pre>

For save

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

For get

<pre><code>Gson gson = new Gson();
String json = mPrefs.getString("MyObject", "");
MyObject obj = gson.fromJson(json, MyObject.class);
</code></pre>

blocks|key|33072|text|正如接受答案中所说的，我们可以保存对象列表，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|33073|public+<T>+void+setList(String+key,+List<T>+list)+{
++++++++Gson+gson+=+new+Gson();
++++++++String+json+=+gson.toJson(list);
++++++++set(key,+json);
++++}

++++public+void+set(String+key,+String+value)+{
++++++++if+(setSharedPreferences+!=+null)+{
++++++++++++SharedPreferences.Editor+prefsEditor+=+setSharedPreferences.edit();
++++++++++++prefsEditor.putString(key,+value);
++++++++++++prefsEditor.commit();
++++++++}
++++}|code-block|syntax|javascript|33074|通过使用以下命令获取它：|33075|public+List<Company>+getCompaniesList(String+key)+{
++++if+(setSharedPreferences+!=+null)+{

++++++++Gson+gson+=+new+Gson();
++++++++List<Company>+companyList;

++++++++String+string+=+setSharedPreferences.getString(key,+null);
++++++++Type+type+=+new+TypeToken<List<Company>>()+{
++++++++}.getType();
++++++++companyList+=+gson.fromJson(string,+type);
++++++++return+companyList;
++++}
++++return+null;
}|33076|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

As said in accepted answer we can save list of objects like:

<pre><code>public &lt;T&gt; void setList(String key, List&lt;T&gt; list) {
 Gson gson = new Gson();
 String json = gson.toJson(list);
 set(key, json);
 }

 public void set(String key, String value) {
 if (setSharedPreferences != null) {
 SharedPreferences.Editor prefsEditor = setSharedPreferences.edit();
 prefsEditor.putString(key, value);
 prefsEditor.commit();
 }
 }
</code></pre>

Get it by using:

<pre><code>public List&lt;Company&gt; getCompaniesList(String key) {
 if (setSharedPreferences != null) {

 Gson gson = new Gson();
 List&lt;Company&gt; companyList;

 String string = setSharedPreferences.getString(key, null);
 Type type = new TypeToken&lt;List&lt;Company&gt;&gt;() {
 }.getType();
 companyList = gson.fromJson(string, type);
 return companyList;
 }
 return null;
}
</code></pre>

blocks|key|33148|text|对我和你来说最好的解决方案是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|33149|private+static+SharedPreferences+sharedPreferences+=+context.getSharedPreferences(STORE_FILE_NAME,+Context.MODE_PRIVATE);
private++SharedPreferences.Editor+editor+=+sharedPreferences.edit();
List<your+object>+list+=+new+ArrayList<>();|code-block|syntax|javascript|33150|对于保存：|33151|editor.edit().putString("your+key+name",+new+Gson().toJson(list)).apply();|33152|对于get：|33153|list+=+new+Gson().fromJson(sharedPreferences.getString("your+key+name",+null),+new+TypeToken<List<your+object+class+name>>(){}.getType());|33154|尽情享受吧！|33155|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

The best solution for me and I think you :

<pre><code>private static SharedPreferences sharedPreferences = context.getSharedPreferences(STORE_FILE_NAME, Context.MODE_PRIVATE);
private SharedPreferences.Editor editor = sharedPreferences.edit();
List&lt;your object&gt; list = new ArrayList&lt;&gt;();
</code></pre>

For save:

<pre><code>editor.edit().putString("your key name", new Gson().toJson(list)).apply();
</code></pre>

For get:

<pre><code>list = new Gson().fromJson(sharedPreferences.getString("your key name", null), new TypeToken&lt;List&lt;your object class name&gt;&gt;(){}.getType());
</code></pre>

enjoy it!

blocks|key|33180|text|首先，您需要创建函数将数组列表保存到SharedPreferences中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|33181|public+void+saveListInLocal(ArrayList<ModelName>+list,+String+key)+{
SharedPreferences+prefs+=+PreferenceManager.getDefaultSharedPreferences(activity);
SharedPreferences.Editor+editor+=+prefs.edit();
Gson+gson+=+new+Gson();
String+json+=+gson.toJson(list);
editor.putString(key,+json);
editor.apply();+++}|code-block|syntax|javascript|33182|您需要创建函数来从SharedPreferences获取数组列表。|33183|public+ArrayList<ModelName>+getListFromLocal(String+key)
{
SharedPreferences+prefs+=+getSharedPreferences("AppName",+Context.MODE_PRIVATE);
Gson+gson+=+new+Gson();
String+json+=+prefs.getString(key,+null);
Type+type+=+new+TypeToken<ArrayList<ModelName>>()+{}.getType();
return+gson.fromJson(json,+type);

}|33184|如何调用保存和检索数组列表函数。|33185|+ArrayList<ModelName>+listSave=new+ArrayList<>();
+listSave.add("test1"));
+listSave.add("test2"));
+saveListInLocal(listSave,"key");
+Log.e("saveArrayList:","Save+ArrayList+success");
+ArrayList<ModelName>+listGet=new+ArrayList<>();
+listGet=getListFromLocal("key");
+Log.e("getArrayList:","Get+ArrayList+size"%2BlistGet.size());|33186|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

First you need to create function to save array list to SharedPreferences.
<pre><code>public void saveListInLocal(ArrayList&lt;ModelName&gt; list, String key) {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(activity);
SharedPreferences.Editor editor = prefs.edit();
Gson gson = new Gson();
String json = gson.toJson(list);
editor.putString(key, json);
editor.apply(); }
</code></pre>
You need to create function to get array list from SharedPreferences.
<pre><code>public ArrayList&lt;ModelName&gt; getListFromLocal(String key)
{
SharedPreferences prefs = getSharedPreferences(&quot;AppName&quot;, Context.MODE_PRIVATE);
Gson gson = new Gson();
String json = prefs.getString(key, null);
Type type = new TypeToken&lt;ArrayList&lt;ModelName&gt;&gt;() {}.getType();
return gson.fromJson(json, type);

}
</code></pre>
How to call save and retrieve array list function.
<pre><code> ArrayList&lt;ModelName&gt; listSave=new ArrayList&lt;&gt;();
 listSave.add(&quot;test1&quot;));
 listSave.add(&quot;test2&quot;));
 saveListInLocal(listSave,&quot;key&quot;);
 Log.e(&quot;saveArrayList:&quot;,&quot;Save ArrayList success&quot;);
 ArrayList&lt;ModelName&gt; listGet=new ArrayList&lt;&gt;();
 listGet=getListFromLocal(&quot;key&quot;);
 Log.e(&quot;getArrayList:&quot;,&quot;Get ArrayList size&quot;+listGet.size());
</code></pre>

blocks|key|33221|text|Kotlin中获取泛型列表的完美函数|type|unstyled|depth|inlineStyleRanges|entityRanges|data|33222|private+fun+<T+:+Serializable>+getGenericList(
++++sharedPreferences:+SharedPreferences,
++++key:+String,
++++clazz:+KClass<T>
):+List<T>+{
++++return+sharedPreferences.let+{+prefs+->
++++++++val+data+=+prefs.getString(key,+null)
++++++++val+type:+Type+=+TypeToken.getParameterized(MutableList::class.java,+clazz.java).type
++++++++gson.fromJson(data,+type)+as+MutableList<T>
++++}
}|code-block|syntax|javascript|33223|您可以调用此函数|33224|getGenericList.(sharedPrefObj,+sharedpref_key,+GenericClass::class)|33225|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

the perfect fucntion for getting generic lists in Kotlin
<pre><code>private fun &lt;T : Serializable&gt; getGenericList(
 sharedPreferences: SharedPreferences,
 key: String,
 clazz: KClass&lt;T&gt;
): List&lt;T&gt; {
 return sharedPreferences.let { prefs -&gt;
 val data = prefs.getString(key, null)
 val type: Type = TypeToken.getParameterized(MutableList::class.java, clazz.java).type
 gson.fromJson(data, type) as MutableList&lt;T&gt;
 }
}
</code></pre>
you can call this function
<pre><code>getGenericList.(sharedPrefObj, sharedpref_key, GenericClass::class)
</code></pre>

I have a list of products, which i retrieve from webservice, when app is opened for first time, app gets product list from webservice. I want to save this list to shared preferences.

<pre><code> List&lt;Product&gt; medicineList = new ArrayList&lt;Product&gt;();
</code></pre>

where Product class is:

<pre><code>public class Product {
 public final String productName;
 public final String price;
 public final String content;
 public final String imageUrl;

 public Product(String productName, String price, String content, String imageUrl) {
 this.productName = productName;
 this.price = price;
 this.content = content;
 this.imageUrl = imageUrl;
 }
}
</code></pre>

how i can save this List not requesting from webservice each time?

How to save List<Object> to SharedPreferences?

SQLite

Kotlin

JSON

Java

我有一个产品列表，我从webservice检索，当应用程序第一次打开时，应用程序从webservice获取产品列表。我要将此列表保存到共享首选项。 List<Product> medicineList = new ArrayList<Product>();其中Product类是：public class Prod...

问如何将List<Object>保存到SharedPreferences？
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