title: How to enable pop-up for lineChart when chartValueSelected using ios-chart API in Swift?
body: <p>I started to learn how to use iOS-charts-API from appcoda.com</p>
  
  <p>I create a LineChart and I don't know how to enable a small pop-up, with the value of the selected entry. Here is two example picture what I am trying to implement: <a href="https://raw.githubusercontent.com/PhilJay/MPChart/master/screenshots/simpledesign_barchart3.png" rel="nofollow">https://raw.githubusercontent.com/PhilJay/MPChart/master/screenshots/simpledesign_barchart3.png</a></p>
  
  <p><a href="http://i.stack.imgur.com/GveGL.png" rel="nofollow">linechart entry selected</a></p>
  
  <p>If I tap on an entry I want to create a popup over it with its value.
  I implemented chartValueSelected function:</p>
  
  <pre><code>func chartValueSelected(chartView: ChartViewBase, entry: ChartDataEntry, dataSetIndex: Int, highlight: ChartHighlight){
  print(entry.value)
  print(highlight.xIndex)}
  </code></pre>
  
  <p>If I run this and tap on an entry, this code is working, so I can see the value on Console, but I think to create a pop-up is a built in function in the API, just I don't know what function should I call or property set.</p>