> <span class="nf">applicationWillFinishLaunching</span><span class="p">(</span><span class="n">_</span> <span class="nv">notification</span><span class="p">:</span> <span class="kt">Notification</span><span class="p">)</span> <span class="p">{</span>

    <span class="c1">/// Define default theme.</span>
    <span class="c1">/// Used on first run. Default: `SystemTheme`.</span>
    <span class="c1">/// Note: `SystemTheme` is a special theme that resolves to `ThemeManager.lightTheme` or `ThemeManager.darkTh