Avoid crash when chipgroup is unchecked

app/src/main/java/net/pokeranalytics/android/ui/fragment/StatisticDetailsFragment.kt

@@ -120,11 +120,18 @@ class StatisticDetailsFragment : PokerAnalyticsFragment() {
 		}
 
 		this.chipGroup.isVisible = displayAggregationChoices
+		this.chipGroup.setSingleSelection(true)
 		this.chipGroup.check(0)
 
 		this.chipGroup.setOnCheckedChangeListener(object : ChipGroupExtension.SingleSelectionOnCheckedListener() {
 			override fun onCheckedChanged(group: ChipGroup, checkedId: Int) {
 				super.onCheckedChanged(group, checkedId)
+
+				@SuppressWarnings
+				if (checkedId < 0) { // when unchecked, checkedId returns -1, causing a crash
+					return
+				}
+
 				val aggregationType = aggregationTypes[checkedId]
 
 				when (aggregationType) {