Minor robustness and UI improvementseel_5.0.1eel_5.0.0eel/5.0.1eel/5.0.05.0.15.0.0

Changes include:
- Change the 'SCAN' label color when scanning.  This visually
  signals to the user that scanning is taking place, which is
  useful with the Kingfisher Si4689 radio where scanning jumps
  to a found station.
- Update the frequency when scanning signals a station is found.
  This improves behavior when using the Kingfisher radio, where
  the frequency update from the binding can fall prey to a race
  with the scanning state change in the QML.
- Explicitly prevent triggering another scan while one is in
  progress.  This is more of a general robustness fix to prevent
  unnecessary calls to the binding.  It does help avoid potential
  issues with the Kingfisher radio where we really cannot interrupt
  a scan at present.

Change-Id: I08825c7f51d354a20b38f647e72e4535bca37bd9
Signed-off-by: Scott Murray <scott.murray@konsulko.com>

2 files changed, 22 insertions, 7 deletions

diff --git a/app/Radio.qml b/app/Radio.qml
index f812af1..7b7797a 100644
--- a/app/Radio.qml
+++ b/app/Radio.qml
@@ -30,7 +30,10 @@ ApplicationWindow {
         property string title
 
         onBandChanged: frequency = minimumFrequency
-        onStationFound: title = stationId
+        onStationFound: {
+            title = stationId
+            scanLabel.color = '#FFFFFF'
+        }
         onFrequencyChanged: {
             title = ''
             slider.value = frequency
@@ -172,6 +175,7 @@ ApplicationWindow {
                         Item { Layout.fillWidth: true }
 
                         Label {
+                            id: scanLabel
                             //Layout.fillWidth: true
                             text: 'SCAN'
                         }
@@ -183,7 +187,10 @@ ApplicationWindow {
                                 triggeredOnStart: true
                                 interval: 100
                                 repeat: true
-                                onTriggered: radio.scanDown()
+                                onTriggered: {
+                                    radio.scanDown()
+                                    scanLabel.color = '#59FF7F'
+                                }
                             }
                         }
 
@@ -194,7 +201,10 @@ ApplicationWindow {
                                 triggeredOnStart: true
                                 interval: 100
                                 repeat: true
-                                onTriggered: radio.scanUp()
+                                onTriggered: {
+                                    radio.scanUp()
+                                    scanLabel.color = '#59FF7F'
+                                }
                             }
                         }
 
diff --git a/app/api/Binding.qml b/app/api/Binding.qml
index 3b43510..7750452 100644
--- a/app/api/Binding.qml
+++ b/app/api/Binding.qml
@@ -106,6 +106,7 @@ WebSocket {
             } else if (event.event === "radio/station_found") {
                 if(scanningState == activeState) {
                     scanningState = stoppedState
+                    frequency = event.data.value
                     stationId = freq2str(event.data.value)
                     root.stationFound()
                 }
@@ -177,13 +178,17 @@ WebSocket {
     }
 
     function scanUp() {
-        scanningState = activeState
-        sendSocketMessage("scan_start", { direction: "forward" })
+        if(scanningState != activeState) {
+            scanningState = activeState
+            sendSocketMessage("scan_start", { direction: "forward" })
+        }
     }
 
     function scanDown() {
-        scanningState = activeState
-        sendSocketMessage("scan_start", { direction: "backward" })
+        if(scanningState != activeState) {
+            scanningState = activeState
+            sendSocketMessage("scan_start", { direction: "backward" })
+        }
     }
 
     function updateFrequencyRange(band) {