n class="p">:(</span><span class="n">UInt16</span><span class="p">)</span><span class="nv">buttonId</span>
                        <span class="nf">systemAction</span><span class="p">:(</span><span class="n">nullable</span> <span class="n"><a href="../Type%20Definitions.html#/c:SDLSystemAction.h@T@SDLSystemAction">SDLSystemAction</a></span><span class="p">)</span><span class="nv">systemAction</span>
                             <span class="nf">handler</span><span class="p">:(</span><span class="n">nullable