| <html devsite="true"> |
| <head> |
| <title>PositionalDataSource</title> |
| {% setvar book_path %}/reference/androidx/_book.yaml{% endsetvar %} |
| {% include "_shared/_reference-head-tags.html" %} |
| </head> |
| <body> |
| <div id="metadata-info-block"></div> |
| <h1>PositionalDataSource</h1> |
| <p> |
| <pre>public abstract class <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> extends <a href="/reference/androidx/paging/DataSource.html">DataSource</a></pre> |
| </p> |
| <div class="devsite-table-wrapper"> |
| <table class="jd-inheritance-table"> |
| <tbody> |
| <tr> |
| <td colspan="3"><a href="https://developer.android.com/reference/java/lang/Object.html">java.lang.Object</a></td> |
| </tr> |
| <tr> |
| <td class="jd-inheritance-space"> ↳</td> |
| <td colspan="2"><a href="/reference/androidx/paging/DataSource.html">androidx.paging.DataSource</a></td> |
| </tr> |
| <tr> |
| <td> </td> |
| <td class="jd-inheritance-space"> ↳</td> |
| <td colspan="1"><a href="/reference/androidx/paging/PositionalDataSource.html">androidx.paging.PositionalDataSource</a></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <hr> |
| <aside class="caution"><strong>This class is deprecated.</strong><br>PositionalDataSource is deprecated and has been replaced by PagingSource</aside> |
| <p>Position-based data loader for a fixed-size, countable data set, supporting fixed-size loads at arbitrary page positions.</p> |
| <p>Extend PositionalDataSource if you can load pages of a requested size at arbitrary positions, and provide a fixed item count. If your data source can't support loading arbitrary requested page sizes (e.g. when network page size constraints are only known at runtime), either use <code><a href="/reference/androidx/paging/PageKeyedDataSource.html">PageKeyedDataSource</a></code> or <code><a href="/reference/androidx/paging/ItemKeyedDataSource.html">ItemKeyedDataSource</a></code>, or pass the initial result with the two parameter <code><a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html#onResult(kotlin.collections.List,kotlin.Int,kotlin.Int)">LoadInitialCallback.onResult</a></code>.</p> |
| <p>Room can generate a Factory of PositionalDataSources for you:</p> |
| <pre class="prettyprint">@Dao<br>interface UserDao {<br> @Query("SELECT * FROM user ORDER BY age DESC")<br> public abstract DataSource.Factory<Integer, User> loadUsersByAgeDesc();<br>}</pre> |
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| <col width="40%"> |
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| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>></code></td> |
| <td> |
| <p>Type of items being loaded by the <code><a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a></code>.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <h2>Summary</h2> |
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| <col width="40%"> |
| <col> |
| </colgroup> |
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| <th colspan="100%"><h3>Nested types</h3></th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td> |
| <div><code>public abstract class <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html">PositionalDataSource.LoadInitialCallback</a><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>></code></div> |
| <p>Callback for <code><a href="/reference/androidx/paging/PositionalDataSource.html#loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams)">loadInitial</a></code> to return data, position, and count.</p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <div><code>public class <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialParams.html">PositionalDataSource.LoadInitialParams</a></code></div> |
| <p>Holder object for inputs to <code><a href="/reference/androidx/paging/PositionalDataSource.html#loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams)">loadInitial</a></code>.</p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <div><code>public abstract class <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeCallback.html">PositionalDataSource.LoadRangeCallback</a><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>></code></div> |
| <p>Callback for PositionalDataSource <code><a href="/reference/androidx/paging/PositionalDataSource.html#loadRange(androidx.paging.PositionalDataSource.LoadRangeParams)">loadRange</a></code> to return data.</p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <div><code>public class <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeParams.html">PositionalDataSource.LoadRangeParams</a></code></div> |
| <p>Holder object for inputs to <code><a href="/reference/androidx/paging/PositionalDataSource.html#loadRange(androidx.paging.PositionalDataSource.LoadRangeParams)">loadRange</a></code>.</p> |
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| </div> |
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| <th colspan="100%"><h3>Public constructors</h3></th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td> |
| <div><code><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#PositionalDataSource()">PositionalDataSource</a>()</code></div> |
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| <th colspan="100%"><h3>Public methods</h3></th> |
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| <tbody class="list"> |
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| <td width="40%"><code>abstract void</code></td> |
| <td> |
| <div><code>@<a href="/reference/androidx/annotation/WorkerThread.html">WorkerThread</a><br><a href="/reference/androidx/paging/PositionalDataSource.html#loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams,androidx.paging.PositionalDataSource.LoadInitialCallback)">loadInitial</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialParams.html">PositionalDataSource.LoadInitialParams</a> params,<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html">PositionalDataSource.LoadInitialCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback<br>)</code></div> |
| <p>Load initial list data.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>abstract void</code></td> |
| <td> |
| <div><code>@<a href="/reference/androidx/annotation/WorkerThread.html">WorkerThread</a><br><a href="/reference/androidx/paging/PositionalDataSource.html#loadRange(androidx.paging.PositionalDataSource.LoadRangeParams,androidx.paging.PositionalDataSource.LoadRangeCallback)">loadRange</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeParams.html">PositionalDataSource.LoadRangeParams</a> params,<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeCallback.html">PositionalDataSource.LoadRangeCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback<br>)</code></div> |
| <p>Called to load a range of data from the DataSource.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <div><code><V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a>(@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function)</code></div> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <div><code><V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#map(kotlin.Function1)">map</a>(@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function)</code></div> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <div><code><V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function<br>)</code></div> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <div><code><V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(kotlin.Function1)">mapByPage</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function<br>)</code></div> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive" id="inhmethods"> |
| <thead> |
| <tr> |
| <th colspan="100%"><h3>Inherited fields</h3></th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td><devsite-expandable><span class="expand-control">From <a href="/reference/androidx/paging/DataSource.html">androidx.paging.DataSource</a></span> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
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| </colgroup> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>boolean</code></td> |
| <td> |
| <div><code><a href="/reference/androidx/paging/DataSource.html#isInvalid()">isInvalid</a></code></div> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </devsite-expandable> </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive" id="inhmethods"> |
| <thead> |
| <tr> |
| <th colspan="100%"><h3>Inherited methods</h3></th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td><devsite-expandable><span class="expand-control">From <a href="/reference/androidx/paging/DataSource.html">androidx.paging.DataSource</a></span> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
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| </colgroup> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>void</code></td> |
| <td> |
| <div><code>@<a href="/reference/androidx/annotation/AnyThread.html">AnyThread</a><br><a href="/reference/androidx/paging/DataSource.html#addInvalidatedCallback(androidx.paging.DataSource.InvalidatedCallback)">addInvalidatedCallback</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/DataSource.InvalidatedCallback.html">DataSource.InvalidatedCallback</a> onInvalidatedCallback<br>)</code></div> |
| <p>Add a callback to invoke when the DataSource is first invalidated.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>void</code></td> |
| <td> |
| <div><code>@<a href="/reference/androidx/annotation/AnyThread.html">AnyThread</a><br><a href="/reference/androidx/paging/DataSource.html#invalidate()">invalidate</a>()</code></div> |
| <p>Signal the data source to stop loading, and notify its callback.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>void</code></td> |
| <td> |
| <div><code>@<a href="/reference/androidx/annotation/AnyThread.html">AnyThread</a><br><a href="/reference/androidx/paging/DataSource.html#removeInvalidatedCallback(androidx.paging.DataSource.InvalidatedCallback)">removeInvalidatedCallback</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/DataSource.InvalidatedCallback.html">DataSource.InvalidatedCallback</a> onInvalidatedCallback<br>)</code></div> |
| <p>Remove a previously added invalidate callback.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </devsite-expandable> </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="list"> |
| <h2>Public constructors</h2> |
| <div class="api-item"><a name="PositionalDataSource--"></a><a name="positionaldatasource"></a> |
| <h3 class="api-name" id="PositionalDataSource()">PositionalDataSource</h3> |
| <pre class="api-signature no-pretty-print">public <T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#PositionalDataSource()">PositionalDataSource</a>()</pre> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><T extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>></code></td> |
| <td> |
| <p>Type of items being loaded by the <code><a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a></code>.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| </div> |
| <div class="list"> |
| <h2>Public methods</h2> |
| <div class="api-item"><a name="loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams, androidx.paging.PositionalDataSource.LoadInitialCallback)"></a><a name="loadInitial-androidx.paging.PositionalDataSource.LoadInitialParams-androidx.paging.PositionalDataSource.LoadInitialCallback-"></a><a name="loadinitial"></a> |
| <h3 class="api-name" id="loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams,androidx.paging.PositionalDataSource.LoadInitialCallback)">loadInitial</h3> |
| <pre class="api-signature no-pretty-print">@<a href="/reference/androidx/annotation/WorkerThread.html">WorkerThread</a><br>public abstract void <a href="/reference/androidx/paging/PositionalDataSource.html#loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams,androidx.paging.PositionalDataSource.LoadInitialCallback)">loadInitial</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialParams.html">PositionalDataSource.LoadInitialParams</a> params,<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html">PositionalDataSource.LoadInitialCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback<br>)</pre> |
| <p>Load initial list data.</p> |
| <p>This method is called to load the initial page(s) from the <code><a href="/reference/androidx/paging/DataSource.html">DataSource</a></code>.</p> |
| <p>LoadResult list must be a multiple of pageSize to enable efficient tiling.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialParams.html">PositionalDataSource.LoadInitialParams</a> params</code></td> |
| <td> |
| <p>Parameters for initial load, including requested start position, load size, and page size.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html">PositionalDataSource.LoadInitialCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback</code></td> |
| <td> |
| <p>Callback that receives initial load data, including position and total data set size.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| <div class="api-item"><a name="loadRange(androidx.paging.PositionalDataSource.LoadRangeParams, androidx.paging.PositionalDataSource.LoadRangeCallback)"></a><a name="loadRange-androidx.paging.PositionalDataSource.LoadRangeParams-androidx.paging.PositionalDataSource.LoadRangeCallback-"></a><a name="loadrange"></a> |
| <h3 class="api-name" id="loadRange(androidx.paging.PositionalDataSource.LoadRangeParams,androidx.paging.PositionalDataSource.LoadRangeCallback)">loadRange</h3> |
| <pre class="api-signature no-pretty-print">@<a href="/reference/androidx/annotation/WorkerThread.html">WorkerThread</a><br>public abstract void <a href="/reference/androidx/paging/PositionalDataSource.html#loadRange(androidx.paging.PositionalDataSource.LoadRangeParams,androidx.paging.PositionalDataSource.LoadRangeCallback)">loadRange</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeParams.html">PositionalDataSource.LoadRangeParams</a> params,<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeCallback.html">PositionalDataSource.LoadRangeCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback<br>)</pre> |
| <p>Called to load a range of data from the DataSource.</p> |
| <p>This method is called to load additional pages from the DataSource after the <code><a href="/reference/androidx/paging/PositionalDataSource.LoadInitialCallback.html">LoadInitialCallback</a></code> passed to dispatchLoadInitial has initialized a <code><a href="/reference/androidx/paging/PagedList.html">PagedList</a></code>.</p> |
| <p>Unlike <code><a href="/reference/androidx/paging/PositionalDataSource.html#loadInitial(androidx.paging.PositionalDataSource.LoadInitialParams)">loadInitial</a></code>, this method must return the number of items requested, at the position requested.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeParams.html">PositionalDataSource.LoadRangeParams</a> params</code></td> |
| <td> |
| <p>Parameters for load, including start position and load size.</p> |
| </td> |
| </tr> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.LoadRangeCallback.html">PositionalDataSource.LoadRangeCallback</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T> callback</code></td> |
| <td> |
| <p>Callback that receives loaded data.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| <div class="api-item"><a name="map-androidx.arch.core.util.Function-"></a><a name="map"></a> |
| <h3 class="api-name" id="map(androidx.arch.core.util.Function)">map</h3> |
| <pre class="api-signature no-pretty-print">public final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> <V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a>(@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function)</pre> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| <p>Same as <code><a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code>, but operates on individual items.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function</code></td> |
| <td> |
| <p>Function that runs on each loaded item, returning items of a potentially new type.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Returns</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <p>A new DataSource, which transforms items using the given function.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">See also</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code></td> |
| <td></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| <div class="api-item"><a name="map-kotlin.Function1-"></a><a name="map"></a> |
| <h3 class="api-name" id="map(kotlin.Function1)">map</h3> |
| <pre class="api-signature no-pretty-print">public final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> <V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#map(kotlin.Function1)">map</a>(@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function)</pre> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| <p>An overload of <code><a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a></code> that accepts a kotlin function type.</p> |
| <p>Same as <code><a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code>, but operates on individual items.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> function</code></td> |
| <td> |
| <p>Function that runs on each loaded item, returning items of a potentially new type.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Returns</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <p>A new DataSource, which transforms items using the given function.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">See also</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| <div class="api-item"><a name="mapByPage-androidx.arch.core.util.Function-"></a><a name="mapbypage"></a> |
| <h3 class="api-name" id="mapByPage(androidx.arch.core.util.Function)">mapByPage</h3> |
| <pre class="api-signature no-pretty-print">public final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> <V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function<br>)</pre> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| <p>Same as <code><a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a></code>, but allows for batch conversions.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/arch/core/util/Function.html">Function</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function</code></td> |
| <td> |
| <p>Function that runs on each loaded page, returning items of a potentially new type.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Returns</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <p>A new DataSource, which transforms items using the given function.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">See also</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code></td> |
| <td></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| <div class="api-item"><a name="mapByPage-kotlin.Function1-"></a><a name="mapbypage"></a> |
| <h3 class="api-name" id="mapByPage(kotlin.Function1)">mapByPage</h3> |
| <pre class="api-signature no-pretty-print">public final @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V> <V extends <a href="https://developer.android.com/reference/java/lang/Object.html">Object</a>> <a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(kotlin.Function1)">mapByPage</a>(<br> @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function<br>)</pre> |
| <p>Applies the given function to each value emitted by the DataSource.</p> |
| <p>An overload of <code><a href="/reference/androidx/paging/PositionalDataSource.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code> that accepts a kotlin function type.</p> |
| <p>Same as <code><a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a></code>, but allows for batch conversions.</p> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Parameters</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> Function1<@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> T>, @<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="https://developer.android.com/reference/java/util/List.html">List</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V>> function</code></td> |
| <td> |
| <p>Function that runs on each loaded page, returning items of a potentially new type.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">Returns</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code>@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> <a href="/reference/androidx/paging/PositionalDataSource.html">PositionalDataSource</a><@<a href="/reference/androidx/annotation/NonNull.html">NonNull</a> V></code></td> |
| <td> |
| <p>A new <code><a href="/reference/androidx/paging/DataSource.html">DataSource</a></code>, which transforms items using the given function.</p> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="devsite-table-wrapper"> |
| <table class="responsive"> |
| <colgroup> |
| <col width="40%"> |
| <col> |
| </colgroup> |
| <thead> |
| <tr> |
| <th colspan="100%">See also</th> |
| </tr> |
| </thead> |
| <tbody class="list"> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/PositionalDataSource.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#map(androidx.arch.core.util.Function)">map</a></code></td> |
| <td></td> |
| </tr> |
| <tr> |
| <td width="40%"><code><a href="/reference/androidx/paging/DataSource.Factory.html#mapByPage(androidx.arch.core.util.Function)">mapByPage</a></code></td> |
| <td></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| </div> |
| </div> |
| </body> |
| </html> |
