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39
40#include <QDebug>
41#include <QTimer>
42
43#include "qshakerecognizer.h"
44
45QShakeSensorGestureRecognizer::QShakeSensorGestureRecognizer(QObject *parent)
46 : QSensorGestureRecognizer(parent)
47 , timerTimeout(450)
48 , active(0)
49 , shaking(0)
50 , shakeCount(0)
51{
52}
53
54QShakeSensorGestureRecognizer::~QShakeSensorGestureRecognizer()
55{
56}
57
58void QShakeSensorGestureRecognizer::create()
59{
60 accel = new QAccelerometer(this);
61 accel->connectToBackend();
62 accel->setDataRate(50);
63
64 qoutputrangelist outputranges = accel->outputRanges();
65
66 if (outputranges.count() > 0)
67 accelRange = (int)(outputranges.at(i: 0).maximum *2) / 9.8; //approx range in g's
68 else
69 accelRange = 4; //this should never happen
70
71 connect(sender: accel,SIGNAL(readingChanged()),receiver: this,SLOT(accelChanged()));
72 timer = new QTimer(this);
73 connect(sender: timer,SIGNAL(timeout()),receiver: this,SLOT(timeout()));
74 timer->setSingleShot(true);
75 timer->setInterval(timerTimeout);
76}
77
78bool QShakeSensorGestureRecognizer::start()
79{
80 active = accel->start();
81 return active;
82}
83
84bool QShakeSensorGestureRecognizer::stop()
85{
86 accel->stop();
87 active = accel->isActive();
88 return !active;
89}
90
91bool QShakeSensorGestureRecognizer::isActive()
92{
93 return active;
94}
95
96QString QShakeSensorGestureRecognizer::id() const
97{
98 return QString("QtSensors.shake");
99}
100
101#define NUMBER_SHAKES 3
102#define THRESHOLD 25
103
104void QShakeSensorGestureRecognizer::accelChanged()
105{
106 qreal x = accel->reading()->x();
107 qreal y = accel->reading()->y();
108 qreal z = accel->reading()->z();
109
110 currentData.x = x;
111 currentData.y = y;
112 currentData.z = z;
113
114 if (qAbs(t: prevData.x - currentData.x) < 1
115 && qAbs(t: prevData.y - currentData.y) < 1
116 && qAbs(t: prevData.z - currentData.z) < 1) {
117 prevData.x = currentData.x;
118 prevData.y = currentData.y;
119 prevData.z = currentData.z;
120 return;
121 }
122
123 bool wasShake = checkForShake(prevSensorData: prevData, currentSensorData: currentData, THRESHOLD);
124 if (!shaking && wasShake &&
125 shakeCount >= NUMBER_SHAKES) {
126 shaking = true;
127 shakeCount = 0;
128 Q_EMIT shake();
129 Q_EMIT detected("shake");
130
131 } else if (wasShake) {
132
133 shakeCount++;
134 if (shakeCount > NUMBER_SHAKES) {
135 timer->start();
136 }
137 }
138
139 prevData.x = currentData.x;
140 prevData.y = currentData.y;
141 prevData.z = currentData.z;
142}
143
144void QShakeSensorGestureRecognizer::timeout()
145{
146 shakeCount = 0;
147 shaking = false;
148}
149
150bool QShakeSensorGestureRecognizer::checkForShake(AccelData prevSensorData, AccelData currentSensorData, qreal threshold)
151{
152 double deltaX = qAbs(t: prevSensorData.x - currentSensorData.x);
153 double deltaY = qAbs(t: prevSensorData.y - currentSensorData.y);
154 double deltaZ = qAbs(t: prevSensorData.z - currentSensorData.z);
155
156 return (deltaX > threshold
157 || deltaY > threshold
158 || deltaZ > threshold);
159}
160
161

source code of qtsensors/src/plugins/sensorgestures/shake/qshakerecognizer.cpp