Added null check to generateFilledPath()

Author: oliverClimbs

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/LineChartRenderer.java

@@ -526,13 +526,15 @@ private void generateFilledPath(final ILineDataSet dataSet, final int startIndex
 
             currentEntry = dataSet.getEntryForIndex(x);
 
-            if (isDrawSteppedEnabled) {
-                filled.lineTo(currentEntry.getX(), previousEntry.getY() * phaseY);
-            }
+            if (currentEntry != null) {
+                if (isDrawSteppedEnabled) {
+                    filled.lineTo(currentEntry.getX(), previousEntry.getY() * phaseY);
+                }
 
-            filled.lineTo(currentEntry.getX(), currentEntry.getY() * phaseY);
+                filled.lineTo(currentEntry.getX(), currentEntry.getY() * phaseY);
 
-            previousEntry = currentEntry;
+                previousEntry = currentEntry;
+            }
         }
 
         // close up