Implement custom element removal with reordering. Works nicely, from observation.

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/actions/NewPostViewModel.kt

@@ -1278,10 +1278,29 @@ open class NewPostViewModel : ViewModel() {
     }
 
     fun removePollOption(optionIndex: Int) {
-        pollOptions.remove(optionIndex)
+        pollOptions.removeOrdered(optionIndex)
         saveDraft()
     }
 
+    private fun MutableMap<Int, String>.removeOrdered(index: Int) {
+        val keyList = keys
+        val elementList = values.toMutableList()
+        run stop@{
+            for (i in index until elementList.size) {
+                val nextIndex = i + 1
+                if (nextIndex == elementList.size) return@stop
+                elementList[i] = elementList[nextIndex].also { elementList[nextIndex] = "null" }
+            }
+        }
+        elementList.removeLast()
+        val newEntries = keyList.zip(elementList) { key, content -> Pair(key, content) }
+        this.clear()
+        this.putAll(newEntries)
+
+        println("Keys collection size(after deletion) :${keys.size}")
+        println("Values collection size(after deletion) :${values.size}")
+    }
+
     fun updatePollOption(
         optionIndex: Int,
         text: String,