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/iosaccelerometer.mm | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'src/plugins/sensors/ios/iosaccelerometer.mm') diff --git a/src/plugins/sensors/ios/iosaccelerometer.mm b/src/plugins/sensors/ios/iosaccelerometer.mm index 570d58ba..dbeef017 100644 --- a/src/plugins/sensors/ios/iosaccelerometer.mm +++ b/src/plugins/sensors/ios/iosaccelerometer.mm @@ -40,6 +40,8 @@ char const * const IOSAccelerometer::id("ios.accelerometer"); QT_BEGIN_NAMESPACE +int IOSAccelerometer::s_startCount = 0; + IOSAccelerometer::IOSAccelerometer(QSensor *sensor) : QSensorBackend(sensor) , m_motionManager([QIOSMotionManager sharedManager]) @@ -52,16 +54,24 @@ IOSAccelerometer::IOSAccelerometer(QSensor *sensor) void IOSAccelerometer::start() { + if (m_timer != 0) + return; + int hz = sensor()->dataRate(); m_timer = startTimer(1000 / (hz == 0 ? 60 : hz)); - [m_motionManager startAccelerometerUpdates]; + if (++s_startCount == 1) + [m_motionManager startAccelerometerUpdates]; } void IOSAccelerometer::stop() { - [m_motionManager stopAccelerometerUpdates]; + if (m_timer == 0) + return; + killTimer(m_timer); m_timer = 0; + if (--s_startCount == 0) + [m_motionManager stopAccelerometerUpdates]; } void IOSAccelerometer::timerEvent(QTimerEvent *) -- cgit v1.2.3