Use default scope for file save and display snr

app/src/main/java/com/geeksville/mesh/MainActivity.kt

@@ -60,11 +60,9 @@ import com.google.android.material.tabs.TabLayoutMediator
 import com.google.protobuf.InvalidProtocolBufferException
 import com.vorlonsoft.android.rate.AppRate
 import com.vorlonsoft.android.rate.StoreType
-import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.*
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.Job
-import kotlinx.coroutines.cancel
 import java.io.FileOutputStream
+import java.lang.Runnable
 import java.nio.charset.Charset
 import java.text.DateFormat
 import java.util.*
@@ -559,10 +557,16 @@ class MainActivity : AppCompatActivity(), Logging,
             CREATE_CSV_FILE -> {
                 if (resultCode == Activity.RESULT_OK) {
                     data?.data?.let { file_uri ->
+                        // model.allPackets is a result of a query, so we need to use observer for
+                        // the query to materialize
                         model.allPackets.observe(this, { packets ->
                             if (packets != null) {
-                                saveMessagesCSV(file_uri, packets)
+                                // no need for observer once got non-null list
                                 model.allPackets.removeObservers(this)
+                                // execute on the default thread pool to not block the main thread
+                                CoroutineScope(Dispatchers.Default + Job()).handledLaunch {
+                                    saveMessagesCSV(file_uri, packets)
+                                }
                             }
                         })
                     }
@@ -1084,11 +1088,8 @@ class MainActivity : AppCompatActivity(), Logging,
                             } else if (my_position != null) {
                                 val dist: Int =
                                     positionToMeter(my_position!!, position).roundToInt()
-                                fs.write(
+                                fs.write("%x,%f,%d,%d".format( packet_proto.from,
-                                    ("${packet_proto.from.toUInt().toString(16)}," +
+                                    packet_proto.rxSnr, packet_proto.rxTime, dist).toByteArray())
-                                            "${packet_proto.rxSnr},${packet_proto.rxTime},$dist\n")
-                                        .toByteArray()
-                                )
                             }
                         }
                     }

app/src/main/java/com/geeksville/mesh/NodeInfo.kt

@@ -67,7 +67,8 @@ data class Position(
 data class NodeInfo(
     val num: Int, // This is immutable, and used as a key
     var user: MeshUser? = null,
-    var position: Position? = null
+    var position: Position? = null,
+    var snr: Float = 1000.0f
 ) : Parcelable {
 
     /// Return the last time we've seen this node in secs since 1970

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

@@ -167,7 +167,7 @@ class MeshService : Service(), Logging {
         // FIXME - currently we don't support location reading without google play
         if (fusedLocationClient == null && isGooglePlayAvailable(this)) {
             GeeksvilleApplication.analytics.track("location_start") // Figure out how many users needed to use the phone GPS
-            
+
             val request = LocationRequest.create().apply {
                 interval = requestInterval
                 priority = LocationRequest.PRIORITY_HIGH_ACCURACY
@@ -713,6 +713,7 @@ class MeshService : Service(), Logging {
                     // Handle new style position info
                     Portnums.PortNum.POSITION_APP_VALUE -> {
                         val u = MeshProtos.Position.parseFrom(data.payload)
+                        debug("position_app ${packet.from} ${u.toOneLineString()}")
                         handleReceivedPosition(packet.from, u, dataPacket.time)
                     }
 
@@ -820,6 +821,7 @@ class MeshService : Service(), Logging {
         defaultTime: Long = System.currentTimeMillis()
     ) {
         updateNodeInfo(fromNum) {
+            debug("update ${it.user?.longName} with ${p.toOneLineString()}")
             it.position = Position(p)
             updateNodeInfoTime(it, (defaultTime / 1000).toInt())
         }
@@ -916,6 +918,7 @@ class MeshService : Service(), Logging {
             updateNodeInfo(fromNum) {
                 // Update our last seen based on any valid timestamps.  If the device didn't provide a timestamp make one
                 updateNodeInfoTime(it, rxTime)
+                it.snr = packet.rxSnr
             }
 
             handleReceivedData(packet)

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

@@ -37,6 +37,7 @@ class UsersFragment : ScreenFragment("Users"), Logging {
         val batteryPctView = itemView.batteryPercentageView
         val lastTime = itemView.lastConnectionView
         val powerIcon = itemView.batteryIcon
+        val snrView = itemView.snrView
     }
 
     private val nodesAdapter = object : RecyclerView.Adapter<ViewHolder>() {
@@ -115,10 +116,16 @@ class UsersFragment : ScreenFragment("Users"), Logging {
             } else {
                 holder.distanceView.visibility = View.INVISIBLE
             }
-
+            debug("node=${n.user?.longName} bat=${n.batteryPctLevel}")
             renderBattery(n.batteryPctLevel, holder)
 
             holder.lastTime.text = getLastTimeValue(n)
+            if ((n.num == ourNodeInfo?.num) || (n.snr > 100f)) {
+                holder.snrView.visibility = View.INVISIBLE
+            } else {
+                holder.snrView.visibility = View.VISIBLE
+                holder.snrView.text = n.snr.toString()
+            }
         }
 
         private var nodes = arrayOf<NodeInfo>()

app/src/main/res/layout/adapter_node_layout.xml

@@ -71,6 +71,16 @@
                 app:layout_constraintEnd_toEndOf="parent"
                 app:layout_constraintTop_toTopOf="@+id/batteryIcon" />
 
+            <TextView
+                android:id="@+id/snrView"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginEnd="8dp"
+                android:layout_marginBottom="8dp"
+                android:text="-8.0"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintEnd_toStartOf="@id/lastCommIcon" />
+
             <ImageView
                 android:id="@+id/lastCommIcon"
                 android:layout_width="wrap_content"