Added delete all messages into the AlertDialog.

app/src/main/java/com/geeksville/mesh/model/MessagesState.kt

@@ -53,6 +53,13 @@ class MessagesState(private val ui: UIViewModel) : Logging {
         messages.value = messagesList
     }
 
+    private fun removeAllMessages() {
+        debug("Removing all messages")
+
+        messagesList.clear()
+        messages.value = messagesList
+    }
+
     fun updateStatus(id: Int, status: MessageStatus) {
         // Super inefficent but this is rare
         debug("Handling message status change $id: $status")
@@ -102,4 +109,16 @@ class MessagesState(private val ui: UIViewModel) : Logging {
         }
         removeMessage(packet)
     }
+
+    fun deleteAllMessages() {
+        val service = ui.meshService
+        if (service != null) {
+            try {
+                service.deleteAllMessages()
+            } catch (ex: RemoteException) {
+
+            }
+            removeAllMessages()
+        }
+    }
 }

app/src/main/java/com/geeksville/mesh/service/MeshService.kt

@@ -1789,6 +1789,10 @@ class MeshService : Service(), Logging {
             }
         }
 
+        override fun deleteAllMessages() {
+            recentDataPackets.clear()
+        }
+
         override fun send(p: DataPacket) {
             toRemoteExceptions {
                 // Init from and id

app/src/main/java/com/geeksville/mesh/ui/MessagesFragment.kt

@@ -173,9 +173,15 @@ class MessagesFragment : ScreenFragment("Messages"), Logging {
                 ) { _, _ ->
                     model.messagesState.deleteMessage((messages[position]), position)
                 }
-                deleteMessageDialog.setNegativeButton(R.string.cancel
+                deleteMessageDialog.setNeutralButton(
+                    R.string.cancel
                 ) { _, _ ->
                 }
+                deleteMessageDialog.setNegativeButton(
+                    R.string.delete_all_messages
+                ) { _, _ ->
+                    model.messagesState.deleteAllMessages()
+                }
                 deleteMessageDialog.create()
                 deleteMessageDialog.show()
                 true