Fix CombinedChartView not draw markers

Source/Charts/Charts/CombinedChartView.swift

@@ -222,4 +222,45 @@ open class CombinedChartView: BarLineChartViewBase, CombinedChartDataProvider
 
     /// - returns: `true` the highlight is be full-bar oriented, `false` ifsingle-value
     open var isHighlightFullBarEnabled: Bool { return highlightFullBarEnabled }
+
+    // MARK:- override drawMarkers
+
+    /// draws all MarkerViews on the highlighted positions. override here for combined chart view's special data structure
+    override func drawMarkers(context: CGContext)
+    {
+        guard
+            let marker = marker, 
+            isDrawMarkersEnabled && valuesToHighlight()
+            else { return }
+
+        for i in 0 ..< _indicesToHighlight.count
+        {
+            let highlight = _indicesToHighlight[i]
+
+            guard 
+                let set = combinedData?.getDataSetByHighlight(highlight),
+                let e = _data?.entryForHighlight(highlight)
+                else { continue }
+
+            let entryIndex = set.entryIndex(entry: e)
+            if entryIndex > Int(Double(set.entryCount) * _animator.phaseX)
+            {
+                continue
+            }
+
+            let pos = getMarkerPosition(highlight: highlight)
+
+            // check bounds
+            if !_viewPortHandler.isInBounds(x: pos.x, y: pos.y)
+            {
+                continue
+            }
+
+            // callbacks to update the content
+            marker.refreshContent(entry: e, highlight: highlight)
+
+            // draw the marker
+            marker.draw(context: context, point: pos)
+        }
+    }
 }

Source/Charts/Data/Implementations/Standard/CombinedChartData.swift

@@ -261,21 +261,18 @@ open class CombinedChartData: BarLineScatterCandleBubbleChartData
         super.notifyDataChanged() // recalculate everything
     }
 
-
     /// Get the Entry for a corresponding highlight object
     ///
     /// - parameter highlight:
     /// - returns: The entry that is highlighted
     open override func entryForHighlight(_ highlight: Highlight) -> ChartDataEntry?
     {
-        let dataObjects = allData
-
-        if highlight.dataIndex >= dataObjects.count
+        if highlight.dataIndex >= allData.count
         {
             return nil
         }
 
-        let data = dataObjects[highlight.dataIndex]
+        let data = dataByIndex(highlight.dataIndex)
 
         if highlight.dataSetIndex >= data.dataSetCount
         {
@@ -292,8 +289,30 @@ open class CombinedChartData: BarLineScatterCandleBubbleChartData
                     return e
                 }
             }
-
             return nil
         }
     }
+
+    /// get data set for highlight
+    ///
+    /// - Parameter highlight: current highlight
+    /// - Returns: dataset related to highlight
+    open func getDataSetByHighlight(_ highlight: Highlight) -> IChartDataSet!
+    {  
+        if highlight.dataIndex >= allData.count
+        {
+            return nil
+        }
+
+        let data = dataByIndex(highlight.dataIndex)
+
+        if highlight.dataSetIndex >= data.dataSetCount
+        {
+            return nil
+        }
+        else
+        {
+            return data.dataSets[highlight.dataSetIndex]
+        }
+    }
 }