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39 
40 #ifndef QGESTUREMANAGER_P_H
41 #define QGESTUREMANAGER_P_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 for the convenience
48 // of other Qt classes.  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 <QtWidgets/private/qtwidgetsglobal_p.h>
55 #include "qobject.h"
56 #include "qbasictimer.h"
57 #include "private/qwidget_p.h"
58 #include "qgesturerecognizer.h"
59 
60 #ifndef QT_NO_GESTURES
61 
62 #include <functional>
63 
64 QT_BEGIN_NAMESPACE
65 
66 class QBasicTimer;
67 class QGraphicsObject;
68 class QGestureManager : public QObject
69 {
70     Q_OBJECT
71 public:
72     QGestureManager(QObject *parent);
73     ~QGestureManager();
74 
75     Qt::GestureType registerGestureRecognizer(QGestureRecognizer *recognizer);
76     void unregisterGestureRecognizer(Qt::GestureType type);
77 
78     bool filterEvent(QWidget *receiver, QEvent *event);
79     bool filterEvent(QObject *receiver, QEvent *event);
80 #if QT_CONFIG(graphicsview)
81     bool filterEvent(QGraphicsObject *receiver, QEvent *event);
82 #endif // QT_CONFIG(graphicsview)
83 
84     enum InstanceCreation { ForceCreation, DontForceCreation };
85 
86     static QGestureManager *instance(InstanceCreation ic = ForceCreation); // declared in qapplication.cpp
87     static bool gesturePending(QObject *o);
88 
89     void cleanupCachedGestures(QObject *target, Qt::GestureType type);
90 
91     void recycle(QGesture *gesture);
92 
93 protected:
94     bool filterEventThroughContexts(const QMultiMap<QObject *, Qt::GestureType> &contexts,
95                                     QEvent *event);
96 
97 private:
98     QMultiMap<Qt::GestureType, QGestureRecognizer *> m_recognizers;
99 
100     QSet<QGesture *> m_activeGestures;
101     QSet<QGesture *> m_maybeGestures;
102 
103     enum State {
104         Gesture,
105         NotGesture,
106         MaybeGesture // this means timers are up and waiting for some
107                      // more events, and input events are handled by
108                      // gesture recognizer explicitly
109     } state;
110 
111     struct ObjectGesture
112     {
113         QObject* object;
114         Qt::GestureType gesture;
115 
ObjectGestureObjectGesture116         ObjectGesture(QObject *o, const Qt::GestureType &g) : object(o), gesture(g) { }
117         inline bool operator<(const ObjectGesture &rhs) const
118         {
119             if (std::less<QObject *>{}(object, rhs.object))
120                 return true;
121             if (object == rhs.object)
122                 return gesture < rhs.gesture;
123             return false;
124         }
125     };
126 
127     QMap<ObjectGesture, QList<QGesture *> > m_objectGestures;
128     QHash<QGesture *, QGestureRecognizer *> m_gestureToRecognizer;
129     QHash<QGesture *, QObject *> m_gestureOwners;
130 
131     QHash<QGesture *, QPointer<QWidget> > m_gestureTargets;
132 
133     int m_lastCustomGestureId;
134 
135     QHash<QGestureRecognizer *, QSet<QGesture *> > m_obsoleteGestures;
136     QHash<QGesture *, QGestureRecognizer *> m_deletedRecognizers;
137     QSet<QGesture *> m_gesturesToDelete;
138     void cleanupGesturesForRemovedRecognizer(QGesture *gesture);
139 
140     QGesture *getState(QObject *widget, QGestureRecognizer *recognizer,
141                        Qt::GestureType gesture);
142     void deliverEvents(const QSet<QGesture *> &gestures,
143                        QSet<QGesture *> *undeliveredGestures);
144     void getGestureTargets(const QSet<QGesture*> &gestures,
145                            QHash<QWidget *, QList<QGesture *> > *conflicts,
146                            QHash<QWidget *, QList<QGesture *> > *normal);
147 
148     void cancelGesturesForChildren(QGesture *originatingGesture);
149 };
150 
151 QT_END_NAMESPACE
152 
153 #endif // QT_NO_GESTURES
154 
155 #endif // QGESTUREMANAGER_P_H
156