blocks|key|4385303|text|考虑使用toMutableList()函数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4385304|presenter.getContacts().toMutableList()|code-block|syntax|javascript|4385305|有一些针对标准库类型的toMutableList()扩展，您可能希望将其转换为可变列表：Collection<T>、Iterable<T>、Sequence<T>、CharSequence、Array<T>和原始数组。|4385306|entityMap|0|LINK|mutability|MUTABLE|url|https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/to-mutable-list.html^0|4|F|4|F|0|0|0|B|F|18|D|1M|B|1Y|B|2A|C|2N|8|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|F|3|G|5|H|7|10|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]|$9|1A|A|1B|B|C]|$9|1C|A|1D|B|C]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|1E|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

Consider using the <a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/to-mutable-list.html" rel="noreferrer"><code>toMutableList()</code></a> function:

<pre><code>presenter.getContacts().toMutableList()
</code></pre>

There are <code>toMutableList()</code> extensions for the stdlib types that one might want to convert to a mutable list: <code>Collection&lt;T&gt;</code>, <code>Iterable&lt;T&gt;</code>, <code>Sequence&lt;T&gt;</code>, <code>CharSequence</code>, <code>Array&lt;T&gt;</code> and primitive arrays.

blocks|key|4384748|text|如果你只想要ArrayList，你可以创建自己的Kotlin扩展。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4384749|fun+<T>+List<T>.toArrayList():+ArrayList<T>{
++++return+ArrayList(this)
}|code-block|syntax|javascript|4384750|然后，您可以在您的应用程序中使用它，如下所示|4384751|myList.toArrayList()|4384752|简单易用|4384753|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

If you only wants ArrayList, you can create your own Kotlin extension.

<pre><code>fun &lt;T&gt; List&lt;T&gt;.toArrayList(): ArrayList&lt;T&gt;{
 return ArrayList(this)
}
</code></pre>

Then you can use it in your application like

<pre><code>myList.toArrayList()
</code></pre>

Simple and easy

blocks|key|4385370|text|如果要将List或MutableList转换为数组，也可以使用toTypedArray()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4385371|/**
+*+Returns+a+*typed*+array+containing+all+of+the+elements+of+this+collection.
+*
+*+Allocates+an+array+of+runtime+type+`T`+having+its+size+equal+to+the+size+of+this+collection
+*+and+populates+the+array+with+the+elements+of+this+collection.
+*+@sample+samples.collections.Collections.Collections.collectionToTypedArray
+*/
@Suppress("UNCHECKED_CAST")
public+actual+inline+fun+<reified+T>+Collection<T>.toTypedArray():+Array<T>+{
++++@Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
++++val+thisCollection+=+this+as+java.util.Collection<T>
++++return+thisCollection.toArray(arrayOfNulls<T>(0))+as+Array<T>
}|code-block|syntax|javascript|4385372|示例|4385373|myMutableList.toTypedArray()|4385374|entityMap^0|4|4|9|B|V|E|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|P|$]]

You can also use <code>toTypedArray()</code> if you want to convert a <code>List</code> or <code>MutableList</code> to Array

<pre><code>/**
 * Returns a *typed* array containing all of the elements of this collection.
 *
 * Allocates an array of runtime type `T` having its size equal to the size of this collection
 * and populates the array with the elements of this collection.
 * @sample samples.collections.Collections.Collections.collectionToTypedArray
 */
@Suppress("UNCHECKED_CAST")
public actual inline fun &lt;reified T&gt; Collection&lt;T&gt;.toTypedArray(): Array&lt;T&gt; {
 @Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
 val thisCollection = this as java.util.Collection&lt;T&gt;
 return thisCollection.toArray(arrayOfNulls&lt;T&gt;(0)) as Array&lt;T&gt;
}
</code></pre>

<h2>Example</h2>

<pre><code>myMutableList.toTypedArray()
</code></pre>

I have a method (<code>getContacts</code>) that returns a <code>List&lt;Contact&gt;</code> and I need to convert this result to a <code>MutableList&lt;Contact&gt;</code>. Currently the best way I can think of doing it is like this:
<pre><code>val contacts: MutableList&lt;Contact&gt; = ArrayList(presenter.getContacts())
</code></pre>
Is there a more idiomatic/&quot;less Java&quot; way to do that?

Kotlin - Most idiomatic way to convert a List to a MutableList

Kotlin

Java

我有一个返回List<Contact>的方法(getContacts)，我需要将结果转换为MutableList<Contact>。目前我能想到的最好的方法是这样做：val contacts: MutableList<Contact> = ArrayList(presenter.getContacts())有没有一种更...

问Kotlin -将列表转换为MutableList的最常用方法
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