Merge pull request #808 from AppDevNext/FixLegendNPE

Fix NPE in Legend

Author: hannesa2

chartLib/src/main/kotlin/info/appdev/charting/components/Legend.kt

@@ -192,6 +192,7 @@ class Legend() : ComponentBase() {
         val formToTextSpace = formToTextSpace.convertDpToPixel()
 
         for (entry in this.entries) {
+            if (entry == null) continue
             val formSize = (if (entry.formSize.isNaN())
                 this.formSize
             else
@@ -365,6 +366,7 @@ class Legend() : ComponentBase() {
                 var i = 0
                 while (i < entryCount) {
                     val e = entries[i]
+                    if (e == null) { i++; continue }
                     val drawingForm = e.form != LegendForm.NONE
                     val formSize = if (e.formSize.isNaN())
                         defaultFormSize
@@ -425,6 +427,7 @@ class Legend() : ComponentBase() {
                 var i = 0
                 while (i < entryCount) {
                     val legendEntry = entries[i]
+                    if (legendEntry == null) { i++; continue }
                     val drawingForm = legendEntry.form != LegendForm.NONE
                     val formSize = if (legendEntry.formSize.isNaN())
                         defaultFormSize