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39
40#ifndef QQUICKPOINTERMULTIHANDLER_H
41#define QQUICKPOINTERMULTIHANDLER_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 "qquickhandlerpoint_p.h"
57#include "qquickpointerdevicehandler_p.h"
58
59QT_BEGIN_NAMESPACE
60
61class QQuickMultiPointHandlerPrivate;
62
63class Q_QUICK_PRIVATE_EXPORT QQuickMultiPointHandler : public QQuickPointerDeviceHandler
64{
65 Q_OBJECT
66 Q_PROPERTY(int minimumPointCount READ minimumPointCount WRITE setMinimumPointCount NOTIFY minimumPointCountChanged)
67 Q_PROPERTY(int maximumPointCount READ maximumPointCount WRITE setMaximumPointCount NOTIFY maximumPointCountChanged)
68 Q_PROPERTY(QQuickHandlerPoint centroid READ centroid NOTIFY centroidChanged)
69
70public:
71 explicit QQuickMultiPointHandler(QQuickItem *parent = nullptr, int minimumPointCount = 2, int maximumPointCount = -1);
72
73 int minimumPointCount() const;
74 void setMinimumPointCount(int c);
75
76 int maximumPointCount() const;
77 void setMaximumPointCount(int maximumPointCount);
78
79 const QQuickHandlerPoint &centroid() const;
80
81signals:
82 void minimumPointCountChanged();
83 void maximumPointCountChanged();
84 void centroidChanged();
85
86protected:
87 struct PointData {
88 PointData() : id(0), angle(0) {}
89 PointData(quint64 id, qreal angle) : id(id), angle(angle) {}
90 quint64 id;
91 qreal angle;
92 };
93
94 bool wantsPointerEvent(QQuickPointerEvent *event) override;
95 void handlePointerEventImpl(QQuickPointerEvent *event) override;
96 void onActiveChanged() override;
97 void onGrabChanged(QQuickPointerHandler *grabber, QQuickEventPoint::GrabTransition transition, QQuickEventPoint *point) override;
98 QVector<QQuickHandlerPoint> &currentPoints();
99 QQuickHandlerPoint &mutableCentroid();
100 bool hasCurrentPoints(QQuickPointerEvent *event);
101 QVector<QQuickEventPoint *> eligiblePoints(QQuickPointerEvent *event);
102 qreal averageTouchPointDistance(const QPointF &ref);
103 qreal averageStartingDistance(const QPointF &ref);
104 qreal averageTouchPointAngle(const QPointF &ref);
105 qreal averageStartingAngle(const QPointF &ref);
106 QVector<PointData> angles(const QPointF &ref) const;
107 static qreal averageAngleDelta(const QVector<PointData> &old, const QVector<PointData> &newAngles);
108 void acceptPoints(const QVector<QQuickEventPoint *> &points);
109 bool grabPoints(const QVector<QQuickEventPoint *> &points);
110 void moveTarget(QPointF pos);
111
112 Q_DECLARE_PRIVATE(QQuickMultiPointHandler)
113};
114
115QT_END_NAMESPACE
116
117QML_DECLARE_TYPE(QQuickMultiPointHandler)
118
119#endif // QQUICKPOINTERMULTIHANDLER_H
120

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