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<h1>Pager</h1>
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<pre>class <a href="/reference/kotlin/androidx/paging/Pager.html">Pager</a>&lt;Key&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>,&nbsp;Value&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>&gt;</pre>
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<p>Primary entry point into Paging; constructor for a reactive stream of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code>.</p>
<p>Each <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code> represents a snapshot of the backing paginated data. Updates to the backing dataset should be represented by a new instance of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code>.</p>
<p>PagingSource.invalidate and calls to AsyncPagingDataDiffer.refresh or PagingDataAdapter.refresh will notify <code><a href="/reference/kotlin/androidx/paging/Pager.html">Pager</a></code> that the backing dataset has been updated and a new <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code> / PagingSource pair will be generated to represent an updated snapshot.</p>
<p><code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code> can be transformed to alter data as it loads, and presented in a <code>RecyclerView</code> via <code>AsyncPagingDataDiffer</code> or <code>PagingDataAdapter</code>.</p>
<p>LiveData support is available as an extension property provided by the <code>androidx.paging:paging-runtime</code> artifact.</p>
<p>RxJava support is available as extension properties provided by the <code>androidx.paging:paging-rxjava2</code> artifact.</p>
<pre class="prettyprint lang-kotlin">
import androidx.paging.insertSeparators
/*
* Create letter separators in an alphabetically sorted list.
*
* For example, if the input is:
* &quot;apple&quot;, &quot;apricot&quot;, &quot;banana&quot;, &quot;carrot&quot;
*
* The operator would output:
* &quot;A&quot;, &quot;apple&quot;, &quot;apricot&quot;, &quot;B&quot;, &quot;banana&quot;, &quot;C&quot;, &quot;carrot&quot;
*/
pagingDataStream.map { pagingData -&gt;
// map outer stream, so we can perform transformations on each paging generation
pagingData.insertSeparators { before: String?, after: String? -&gt;
if (after != null &amp;&amp; before?.first() != after.first()) {
// separator - after is first item that starts with its first letter
after.first().toUpperCase().toString()
} else {
// no separator - either end of list, or first letters of before/after are the same
null
}
}
}</pre>
<h2>Summary</h2>
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<th colspan="100%"><h3>Public constructors</h3></th>
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<div><code>@<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a><br>@<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-opt-in/index.html">OptIn</a>(markerClass&nbsp;=&nbsp;)<br>&lt;Key&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>,&nbsp;Value&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>&gt; <a href="/reference/kotlin/androidx/paging/Pager.html#Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,kotlin.Function0)">Pager</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;config:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>,<br>&nbsp;&nbsp;&nbsp;&nbsp;initialKey:&nbsp;Key?,<br>&nbsp;&nbsp;&nbsp;&nbsp;pagingSourceFactory:&nbsp;() <span style="white-space: nowrap;">-&gt;</span> <a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;<br>)</code></div>
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<div><code>@<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a><br>&lt;Key&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>,&nbsp;Value&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>&gt; <a href="/reference/kotlin/androidx/paging/Pager.html#Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,[Error type: Unresolved type for RemoteMediator&lt;Key, Value&gt;],kotlin.Function0)">Pager</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;config:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>,<br>&nbsp;&nbsp;&nbsp;&nbsp;initialKey:&nbsp;Key?,<br>&nbsp;&nbsp;&nbsp;&nbsp;remoteMediator:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;?,<br>&nbsp;&nbsp;&nbsp;&nbsp;pagingSourceFactory:&nbsp;() <span style="white-space: nowrap;">-&gt;</span> <a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;<br>)</code></div>
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<td><code><a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;<a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a>&lt;Value&gt;&gt;</code></td>
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<div><code><a href="/reference/kotlin/androidx/paging/Pager.html#flow()">flow</a></code></div>
<p>A cold Flow of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code>, which emits new instances of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code> once they become invalidated by PagingSource.invalidate or calls to AsyncPagingDataDiffer.refresh or PagingDataAdapter.refresh.</p>
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<div class="api-item"><a name="Pager([Error type: Unresolved type for PagingConfig], kotlin.Any, kotlin.Function0)"></a><a name="Pager-[Error type: Unresolved type for PagingConfig]-kotlin.Any-kotlin.Function0-"></a><a name="pager"></a>
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<h3 id="Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,kotlin.Function0)">Pager</h3>
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<pre class="api-signature no-pretty-print">@<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a><br>@<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-opt-in/index.html">OptIn</a>(markerClass&nbsp;=&nbsp;)<br>&lt;Key&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>,&nbsp;Value&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>&gt; <a href="/reference/kotlin/androidx/paging/Pager.html#Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,kotlin.Function0)">Pager</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;config:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>,<br>&nbsp;&nbsp;&nbsp;&nbsp;initialKey:&nbsp;Key? = null,<br>&nbsp;&nbsp;&nbsp;&nbsp;pagingSourceFactory:&nbsp;() <span style="white-space: nowrap;">-&gt;</span> <a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;<br>)</pre>
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<div class="api-item"><a name="Pager([Error type: Unresolved type for PagingConfig], kotlin.Any, [Error type: Unresolved type for RemoteMediator&lt;Key, Value&gt;], kotlin.Function0)"></a><a name="Pager-[Error type: Unresolved type for PagingConfig]-kotlin.Any-[Error type: Unresolved type for RemoteMediator&lt;Key, Value&gt;]-kotlin.Function0-"></a><a name="pager"></a>
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<h3 id="Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,[Error type: Unresolved type for RemoteMediator&lt;Key, Value&gt;],kotlin.Function0)">Pager</h3>
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<pre class="api-signature no-pretty-print">@<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a><br>&lt;Key&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>,&nbsp;Value&nbsp;:&nbsp;<a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html">Any</a>&gt; <a href="/reference/kotlin/androidx/paging/Pager.html#Pager([Error type: Unresolved type for PagingConfig],kotlin.Any,[Error type: Unresolved type for RemoteMediator&lt;Key, Value&gt;],kotlin.Function0)">Pager</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;config:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>,<br>&nbsp;&nbsp;&nbsp;&nbsp;initialKey:&nbsp;Key? = null,<br>&nbsp;&nbsp;&nbsp;&nbsp;remoteMediator:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;?,<br>&nbsp;&nbsp;&nbsp;&nbsp;pagingSourceFactory:&nbsp;() <span style="white-space: nowrap;">-&gt;</span> <a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;Key,&nbsp;Value&gt;<br>)</pre>
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<td><code>config:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a></code></td>
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<p>The configuration</p>
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<h2>Public properties</h2>
<div class="api-item"><a name="getFlow()"></a><a name="setFlow()"></a><a name="getFlow--"></a><a name="setFlow--"></a>
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<h3 id="flow()">flow</h3>
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<pre class="api-signature no-pretty-print">val&nbsp;<a href="/reference/kotlin/androidx/paging/Pager.html#flow()">flow</a>:&nbsp;<a href="/reference/kotlin/[JVM root]/&lt;Error class: unknown class&gt;.html">&lt;Error class: unknown class&gt;</a>&lt;<a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a>&lt;Value&gt;&gt;</pre>
<p>A cold Flow of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code>, which emits new instances of <code><a href="/reference/kotlin/androidx/paging/PagingData.html">PagingData</a></code> once they become invalidated by PagingSource.invalidate or calls to AsyncPagingDataDiffer.refresh or PagingDataAdapter.refresh.</p>
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