ult) prevents your listener from being
garbage-collected. A weak reference does not.</p>
<p>Class-level member functions are not subject to
garbage collection, so you can set
<code>useWeakReference</code> to <code><a href="../../Bool.html">true</a></code>
for class-level member functions without
subjecting them to garbage collection. If you set
<code>useWeakReference</code> to <code><a href="../../Bool.html">true</a></code>
for a listener that is a nested inner function,
the function will be garbage-collect