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39
40#ifndef QQUICKTAPHANDLER_H
41#define QQUICKTAPHANDLER_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include "qquickitem.h"
55#include "qevent.h"
56#include "qquicksinglepointhandler_p.h"
57#include <QtCore/qbasictimer.h>
58
59QT_BEGIN_NAMESPACE
60
61class Q_QUICK_PRIVATE_EXPORT QQuickTapHandler : public QQuickSinglePointHandler
62{
63 Q_OBJECT
64 Q_PROPERTY(bool pressed READ isPressed NOTIFY pressedChanged)
65 Q_PROPERTY(int tapCount READ tapCount NOTIFY tapCountChanged)
66 Q_PROPERTY(qreal timeHeld READ timeHeld NOTIFY timeHeldChanged)
67 Q_PROPERTY(qreal longPressThreshold READ longPressThreshold WRITE setLongPressThreshold NOTIFY longPressThresholdChanged)
68 Q_PROPERTY(GesturePolicy gesturePolicy READ gesturePolicy WRITE setGesturePolicy NOTIFY gesturePolicyChanged)
69
70 QML_NAMED_ELEMENT(TapHandler)
71 QML_ADDED_IN_MINOR_VERSION(12)
72
73public:
74 enum GesturePolicy {
75 DragThreshold,
76 WithinBounds,
77 ReleaseWithinBounds
78 };
79 Q_ENUM(GesturePolicy)
80
81 explicit QQuickTapHandler(QQuickItem *parent = nullptr);
82
83 bool isPressed() const { return m_pressed; }
84
85 int tapCount() const { return m_tapCount; }
86 qreal timeHeld() const { return (m_holdTimer.isValid() ? m_holdTimer.elapsed() / 1000.0 : -1.0); }
87
88 qreal longPressThreshold() const;
89 void setLongPressThreshold(qreal longPressThreshold);
90
91 GesturePolicy gesturePolicy() const { return m_gesturePolicy; }
92 void setGesturePolicy(GesturePolicy gesturePolicy);
93
94Q_SIGNALS:
95 void pressedChanged();
96 void tapCountChanged();
97 void timeHeldChanged();
98 void longPressThresholdChanged();
99 void gesturePolicyChanged();
100 void tapped(QQuickEventPoint *eventPoint);
101 void singleTapped(QQuickEventPoint *eventPoint);
102 void doubleTapped(QQuickEventPoint *eventPoint);
103 void longPressed();
104
105protected:
106 void onGrabChanged(QQuickPointerHandler *grabber, QQuickEventPoint::GrabTransition transition, QQuickEventPoint *point) override;
107 void timerEvent(QTimerEvent *event) override;
108 bool wantsEventPoint(QQuickEventPoint *point) override;
109 void handleEventPoint(QQuickEventPoint *point) override;
110
111private:
112 void setPressed(bool press, bool cancel, QQuickEventPoint *point);
113 int longPressThresholdMilliseconds() const;
114 void connectPreRenderSignal(bool conn = true);
115 void updateTimeHeld();
116
117private:
118 QPointF m_lastTapPos;
119 qreal m_lastTapTimestamp = 0;
120 QElapsedTimer m_holdTimer;
121 QBasicTimer m_longPressTimer;
122 int m_tapCount = 0;
123 int m_longPressThreshold = -1;
124 GesturePolicy m_gesturePolicy = GesturePolicy::DragThreshold;
125 bool m_pressed = false;
126
127 static qreal m_multiTapInterval;
128 static int m_mouseMultiClickDistanceSquared;
129 static int m_touchMultiTapDistanceSquared;
130};
131
132QT_END_NAMESPACE
133
134QML_DECLARE_TYPE(QQuickTapHandler)
135
136#endif // QQUICKTAPHANDLER_H
137

source code of qtdeclarative/src/quick/handlers/qquicktaphandler_p.h