Merge pull request #569 from AltBeacon/stop-scanning-on-unbind

Prevent scanning being left on after unbind
AltBeacon · Aug 29, 2017 · f9df156 · f9df156
2 parents 0c23e14 + d170b8c
commit f9df156
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Showing 3 changed files with 45 additions and 9 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,9 @@
+### Development
+
+Bug Fixes:
+- Turn off scanning after unbind, which was previously left on forever in some cases.
+  (#569, David G. Young)
+
 ### 2.12.1 / 2017-08-16
 
 Bug Fixes:

diff --git a/src/main/java/org/altbeacon/beacon/BeaconManager.java b/src/main/java/org/altbeacon/beacon/BeaconManager.java
@@ -405,21 +405,23 @@ public void bind(@NonNull BeaconConsumer consumer) {
             LogManager.w(TAG, "This device does not support bluetooth LE.  Will not start beacon scanning.");
             return;
         }
-        if (mScheduledScanJobsEnabled) {
-            LogManager.d(TAG, "Not starting beacon scanning service. Using scheduled jobs");
-            consumer.onBeaconServiceConnect();
-            return;
-        }
         synchronized (consumers) {
             ConsumerInfo newConsumerInfo = new ConsumerInfo();
             ConsumerInfo alreadyBoundConsumerInfo = consumers.putIfAbsent(consumer, newConsumerInfo);
             if (alreadyBoundConsumerInfo != null) {
                 LogManager.d(TAG, "This consumer is already bound");
             }
             else {
-                LogManager.d(TAG, "This consumer is not bound.  binding: %s", consumer);
-                Intent intent = new Intent(consumer.getApplicationContext(), BeaconService.class);
-                consumer.bindService(intent, newConsumerInfo.beaconServiceConnection, Context.BIND_AUTO_CREATE);
+                LogManager.d(TAG, "This consumer is not bound.  Binding now: %s", consumer);
+                if (mScheduledScanJobsEnabled) {
+                    LogManager.d(TAG, "Not starting beacon scanning service. Using scheduled jobs");
+                    consumer.onBeaconServiceConnect();
+                }
+                else {
+                    LogManager.d(TAG, "Binding to service");
+                    Intent intent = new Intent(consumer.getApplicationContext(), BeaconService.class);
+                    consumer.bindService(intent, newConsumerInfo.beaconServiceConnection, Context.BIND_AUTO_CREATE);
+                }
                 LogManager.d(TAG, "consumer count is now: %s", consumers.size());
             }
         }
@@ -439,7 +441,12 @@ public void unbind(@NonNull BeaconConsumer consumer) {
         synchronized (consumers) {
             if (consumers.containsKey(consumer)) {
                 LogManager.d(TAG, "Unbinding");
-                consumer.unbindService(consumers.get(consumer).beaconServiceConnection);
+                if (mScheduledScanJobsEnabled) {
+                    LogManager.d(TAG, "Not unbinding from scanning service as we are using scan jobs.");
+                }
+                else {
+                    consumer.unbindService(consumers.get(consumer).beaconServiceConnection);
+                }
                 consumers.remove(consumer);
                 if (consumers.size() == 0) {
                     // If this is the last consumer to disconnect, the service will exit
@@ -449,6 +456,11 @@ public void unbind(@NonNull BeaconConsumer consumer) {
                     // This way when we restart ranging or monitoring it will always be in
                     // foreground mode
                     mBackgroundMode = false;
+                    // If we are using scan jobs, we cancel the active scan job
+                    if (mScheduledScanJobsEnabled) {
+                        // TODO: Cancel the active scan job.  Without this is keeps scanning as if
+                        // a consumer is bound.
+                    }
                 }
             }
             else {

diff --git a/src/main/java/org/altbeacon/beacon/service/scanner/CycledLeScanner.java b/src/main/java/org/altbeacon/beacon/service/scanner/CycledLeScanner.java
@@ -48,6 +48,10 @@ public abstract class CycledLeScanner {
     private boolean mScanningEnabled = false;
     protected final Context mContext;
     private long mScanPeriod;
+    // indicates that we decided not to turn scanning off at the end of a scan cycle (e.g. to
+    // avoid doing too many scans in a limited time on Android 7.0 or because we are capable of
+    // multiple detections.  If true, it indicates scanning needs to be stopped when we finish.
+    private boolean mScanningLeftOn = false;
 
     protected long mBetweenScanPeriod;
 
@@ -224,6 +228,17 @@ public void stop() {
         mScanningEnabled = false;
         if (mScanCyclerStarted) {
             scanLeDevice(false);
+            // If we have left scanning on between scan periods, now is the time to shut it off.
+            if (mScanningLeftOn) {
+                LogManager.d(TAG, "Stopping scanning previously left on.");
+                mScanningLeftOn = false;
+                try {
+                    LogManager.d(TAG, "stopping bluetooth le scan");
+                    finishScan();
+                } catch (Exception e) {
+                    LogManager.w(e, TAG, "Internal Android exception scanning for beacons");
+                }
+            }
         } else {
             LogManager.d(TAG, "scanning already stopped");
         }
@@ -397,18 +412,21 @@ private void finishScanCycle() {
                                 LogManager.d(TAG, "Not stopping scan because this is Android N and we" +
                                         " keep scanning for a minimum of 6 seconds at a time. "+
                                         "We will stop in "+(ANDROID_N_MIN_SCAN_CYCLE_MILLIS-(now-mLastScanCycleStartTime))+" millisconds.");
+                                mScanningLeftOn = true;
                             }
                             else {
                                 try {
                                     LogManager.d(TAG, "stopping bluetooth le scan");
                                     finishScan();
+                                    mScanningLeftOn = false;
                                 } catch (Exception e) {
                                     LogManager.w(e, TAG, "Internal Android exception scanning for beacons");
                                 }
                             }
                         }
                         else {
                             LogManager.d(TAG, "Not stopping scanning.  Device capable of multiple indistinct detections per scan.");
+                            mScanningLeftOn = true;
                         }
 
                         mLastScanCycleEndTime = SystemClock.elapsedRealtime();