title: Add point when user clicks on Charts - 'LineChartView' (iOS-Charts)
body: <p>There's a way to implement a method where, when user clicks on chart, I can know the x-y values to insert in my array?</p>
  
  <p>I'm trying to use:</p>
  
  <pre><code>func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {}
  </code></pre>
  
  <p>but this method shows me the nearest point that I already have.</p>
  
  <p>If I use:</p>
  
  <pre><code>@IBOutlet var chart: LineChartView! 
  
  let tap = UITapGestureRecognizer(target: self, action: #selector(self.longTouch(_:)))
  self.chartView.addGestureRecognizer(tap)
  
  func touch(_ sender: UIGestureRecognizer) {
      let touchPoint = sender.location(in: self.chart)
  }
  </code></pre>
  
  <p>the 'touchPoint' return the absolute view's x-y and not related to the chart.</p>
  
  <p>Someone can help me? Thanks!</p>