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Diffstat (limited to 'docs/html/training/load-data-background/define-launch-query.jd')
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diff --git a/docs/html/training/load-data-background/define-launch-query.jd b/docs/html/training/load-data-background/define-launch-query.jd deleted file mode 100644 index f7978f4a8984..000000000000 --- a/docs/html/training/load-data-background/define-launch-query.jd +++ /dev/null @@ -1,83 +0,0 @@ -page.title=Defining and Launching the Query -trainingnavtop=true -startpage=true - -@jd:body - -<!-- This is the training bar --> -<div id="tb-wrapper"> - <div id="tb"> -<h2>This lesson teaches you to</h2> -<ol> - <li> - <a href="#DefineLaunch">Define and Launch the Query</a> - </li> -</ol> - </div> -</div> - -<p> - To perform a query, create the {@link android.support.v4.content.CursorLoader}, set up its - query, and pass it to the loader framework. From then on, the framework manages everything. - It runs the query on a background thread, returns the results to the foreground, and - watches for changes to the data associated with the query. -</p> -<p> - Pass a {@link android.support.v4.content.CursorLoader} to the loader framework in - your implementation of - {@link android.support.v4.app.LoaderManager.LoaderCallbacks#onCreateLoader onCreateLoader()}. - The loader framework calls this method when you <i>create</i> a loader by calling - {@link android.support.v4.app.LoaderManager#initLoader initLoader()}. You can create - a {@link android.support.v4.content.CursorLoader} anywhere, - but the preferred way is to create it in - {@link android.support.v4.app.LoaderManager.LoaderCallbacks#onCreateLoader onCreateLoader()}, - because this defers creation until the object is actually needed. -</p> -<p> - Notice that {@link android.support.v4.app.LoaderManager#initLoader initLoader()} will only - {@link android.support.v4.app.LoaderManager.LoaderCallbacks#onCreateLoader onCreateLoader()} - if the {@link android.support.v4.content.CursorLoader} doesn't already exist; otherwise, it - re-uses the existing {@link android.support.v4.content.CursorLoader}. The loader framework - tracks {@link android.support.v4.content.CursorLoader} instance using the <code>id</code> - value passed to {@link android.support.v4.app.LoaderManager#initLoader initLoader()}. -</p> -<h2 id="DefineLaunch">Define and Launch the Query</h2> -<p> - To create a {@link android.support.v4.content.CursorLoader} and define its - query at the same time, call the constructor -{@link android.support.v4.content.CursorLoader#CursorLoader(Context, Uri, String[], String, String[], String) - CursorLoader(context, uri, projection, selection, selectionArgs, sortOrder)}. The - <code>context</code> and <code>uri</code> arguments are required, but the others are optional. - To use the default value for an optional argument, pass in <code>null</code>. The - {@link android.support.v4.content.CursorLoader} runs the query against the - {@link android.content.ContentProvider} identified by <code>uri</code>, just as if you had - called {@link android.content.ContentResolver#query ContentResolver.query()} with the same - arguments. -</p> -<p> - For example: -</p> -<pre> -public Loader<Cursor> onCreateLoader(int loaderID, Bundle bundle) -{ - /* - * Takes action based on the ID of the Loader that's being created - */ - switch (loaderID) { - case URL_LOADER: - /* - * Return a new CursorLoader - */ - return new CursorLoader( - this, // Context - DataProviderContract.IMAGE_URI, // Provider's content URI - PROJECTION, // Columns to return - null, // Return all rows - null, // No search arguments - null); // Default search order - default: - // An invalid id was passed in - return null; - } -} -</pre> |