Show and hide line chart highlight on touch
<p>I want to only highlight a data point when the finger is on the chart, as soon as it lifts off the screen I want to call, or simple deselect the highlight.</p>

<pre><code>func chartValueNothingSelected(chartView: ChartViewBase) {
    print("Nothing Selected")
    markerView.hidden = true
}
</code></pre>

<p>I've tried to override the touch ended but haven't gotten it to work.</p>