winrt: Stop LE device watcher when discovery is finished

In order to protect ourselves from late callbacks we have to unregister
the LE watcher's callback as soon as we signal, that we are done with
device discovery. We do not expect any additional devices afterwards and
might run into a late callback otherwise, so we should stop the watcher
immediately and not wait until worker destruction.

Change-Id: I85520a4724397aeb5a693d2c8b940a72d68d9663
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent_winrt.cpp b/src/bluetooth/qbluetoothdevicediscoveryagent_winrt.cpp
index 5dad5ee7..e0209693 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent_winrt.cpp
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent_winrt.cpp
@@ -136,7 +136,7 @@ public:
     explicit QWinRTBluetoothDeviceDiscoveryWorker(QBluetoothDeviceDiscoveryAgent::DiscoveryMethods methods);
     ~QWinRTBluetoothDeviceDiscoveryWorker();
     void start();
-    void stop();
+    void stopLEWatcher();
 
 private:
     void startDeviceDiscovery(QBluetoothDeviceDiscoveryAgent::DiscoveryMethod mode);
@@ -213,7 +213,7 @@ QWinRTBluetoothDeviceDiscoveryWorker::QWinRTBluetoothDeviceDiscoveryWorker(QBlue
 
 QWinRTBluetoothDeviceDiscoveryWorker::~QWinRTBluetoothDeviceDiscoveryWorker()
 {
-    stop();
+    stopLEWatcher();
 #ifdef CLASSIC_APP_BUILD
     CoUninitialize();
 #endif
@@ -235,7 +235,7 @@ void QWinRTBluetoothDeviceDiscoveryWorker::start()
     qCDebug(QT_BT_WINRT) << "Worker started";
 }
 
-void QWinRTBluetoothDeviceDiscoveryWorker::stop()
+void QWinRTBluetoothDeviceDiscoveryWorker::stopLEWatcher()
 {
     if (m_leWatcher) {
         HRESULT hr = m_leWatcher->Stop();
@@ -430,6 +430,7 @@ void QWinRTBluetoothDeviceDiscoveryWorker::setupLEDeviceWatcher()
 void QWinRTBluetoothDeviceDiscoveryWorker::finishDiscovery()
 {
     emit scanFinished();
+    stopLEWatcher();
     deleteLater();
 }
 
@@ -875,7 +876,7 @@ void QBluetoothDeviceDiscoveryAgentPrivate::stop()
 {
     Q_Q(QBluetoothDeviceDiscoveryAgent);
     if (worker) {
-        worker->stop();
+        worker->stopLEWatcher();
         disconnectAndClearWorker();
         emit q->canceled();
     }