Fixes #7 : Validate player stack if adding a new position row

app/src/main/java/net/pokeranalytics/android/ui/modules/handhistory/HandHistoryFragment.kt

@@ -354,6 +354,10 @@ class HandHistoryFragment : RealmFragment(), RowRepresentableDelegate, KeyboardL
 
 	override fun onRowValueChanged(value: Any?, row: RowRepresentable) {
 
+		if (this.model.selectionLiveData.value != null) {
+			this.model.amountValidated() // validates any edited amount before possibly clearing action
+		}
+
 		when (row) {
 			HandRowType.COMMENT -> {
 				this.model.handHistory.comment = value as? String

app/src/main/java/net/pokeranalytics/android/ui/modules/handhistory/model/HandHistoryViewModel.kt

@@ -503,11 +503,15 @@ class HandHistoryViewModel : ViewModel(), RowRepresentableDataSource, CardCentra
 	 */
 	fun amountValidated() {
 
+		if (this.currentAmount?.isEmpty() == true) {
+			return
+		}
+
 		val amount = try {
 			this.currentAmount?.toDouble()
 		} catch (e: NumberFormatException) {
 			Timber.w("Parsing exception: ${e.message}")
-			null
+			return
 		}
 
 		when (val row = this.rowRepresentables[this.currentSelection.index]) {