From 46d9a630a88fc5388dec7fd99289d0e9e0e1f680 Mon Sep 17 00:00:00 2001 From: Richard Moe Gustavsen Date: Wed, 24 Aug 2016 14:19:40 +0200 Subject: iOS: protect OS sensors from being stopped when shared by several Qt sensors When a Qt sensor is told to stop, it automatically stops the underlying OS sensor as well. This caused a problem when several Qt sensors were running, since stopping one would stop them all. This patch will add a ref count for each affected sensor, so that we keep track of when it's safe to start and stop the underlying OS sensor. Task-number: QTBUG-54977 Change-Id: If06c4daac22916feef2f4c7bd521363d74f342a6 Reviewed-by: Edward Welbourne Reviewed-by: Lorn Potter --- src/plugins/sensors/ios/iosmagnetometer.mm | 32 ++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-) (limited to 'src/plugins/sensors/ios/iosmagnetometer.mm') diff --git a/src/plugins/sensors/ios/iosmagnetometer.mm b/src/plugins/sensors/ios/iosmagnetometer.mm index 6c4fbaad..5326a762 100644 --- a/src/plugins/sensors/ios/iosmagnetometer.mm +++ b/src/plugins/sensors/ios/iosmagnetometer.mm @@ -38,6 +38,9 @@ QT_BEGIN_NAMESPACE char const * const IOSMagnetometer::id("ios.magnetometer"); +int IOSMagnetometer::s_magnetometerStartCount = 0; +int IOSMagnetometer::s_deviceMotionStartCount = 0; + IOSMagnetometer::IOSMagnetometer(QSensor *sensor) : QSensorBackend(sensor) , m_motionManager([QIOSMotionManager sharedManager]) @@ -55,24 +58,37 @@ IOSMagnetometer::IOSMagnetometer(QSensor *sensor) void IOSMagnetometer::start() { + if (m_timer != 0) + return; + int hz = sensor()->dataRate(); m_timer = startTimer(1000 / (hz == 0 ? 60 : hz)); m_returnGeoValues = static_cast(sensor())->returnGeoValues(); - if (m_returnGeoValues) - [m_motionManager startDeviceMotionUpdates]; - else - [m_motionManager startMagnetometerUpdates]; + if (m_returnGeoValues) { + if (++s_deviceMotionStartCount == 1) + [m_motionManager startDeviceMotionUpdates]; + } else { + if (++s_magnetometerStartCount == 1) + [m_motionManager startMagnetometerUpdates]; + } } void IOSMagnetometer::stop() { - if (m_returnGeoValues) - [m_motionManager stopDeviceMotionUpdates]; - else - [m_motionManager stopMagnetometerUpdates]; + if (m_timer == 0) + return; + killTimer(m_timer); m_timer = 0; + + if (m_returnGeoValues) { + if (--s_deviceMotionStartCount == 0) + [m_motionManager stopDeviceMotionUpdates]; + } else { + if (--s_magnetometerStartCount == 0) + [m_motionManager stopMagnetometerUpdates]; + } } void IOSMagnetometer::timerEvent(QTimerEvent *) -- cgit v1.2.3