ullable
                    <a href="Loader.ReleaseCallback.html" title="interface in com.google.android.exoplayer2.upstream">Loader.ReleaseCallback</a>&nbsp;callback)</pre>
<div class="deprecationBlock"><span class="deprecatedLabel">Deprecated.</span></div>
<div class="block">Releases the loader. This method should be called when the loader is no longer required.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>callback</code> - An optional callback to be called on the loading thre