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39
40#ifndef QQUICKFLICKABLEBEHAVIOR_H
41#define QQUICKFLICKABLEBEHAVIOR_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/* ### Platform specific flickable mechanics are defined either here, or in
55 mkspec files. Long-term (QtQuick 3) Flickable needs to allow such
56 mechanic details to be controlled via QML so that platforms can easily
57 load custom behavior at QML compile time.
58*/
59
60// The maximum number of pixels a flick can overshoot
61#ifndef QML_FLICK_OVERSHOOT
62#define QML_FLICK_OVERSHOOT 150
63#endif
64
65// The number of samples to use in calculating the velocity of a flick
66#ifndef QML_FLICK_SAMPLEBUFFER
67#define QML_FLICK_SAMPLEBUFFER 3
68#endif
69
70// The number of samples to discard when calculating the flick velocity.
71// Touch panels often produce inaccurate results as the finger is lifted.
72#ifndef QML_FLICK_DISCARDSAMPLES
73#define QML_FLICK_DISCARDSAMPLES 0
74#endif
75
76// The default maximum velocity of a flick.
77#ifndef QML_FLICK_DEFAULTMAXVELOCITY
78# define QML_FLICK_DEFAULTMAXVELOCITY 2500
79#endif
80
81// The default deceleration of a flick.
82#ifndef QML_FLICK_DEFAULTDECELERATION
83# define QML_FLICK_DEFAULTDECELERATION 1500
84#endif
85
86// How much faster to decelerate when overshooting
87#ifndef QML_FLICK_OVERSHOOTFRICTION
88#define QML_FLICK_OVERSHOOTFRICTION 8
89#endif
90
91// Multiflick acceleration minimum flick velocity threshold
92#ifndef QML_FLICK_MULTIFLICK_THRESHOLD
93#define QML_FLICK_MULTIFLICK_THRESHOLD 1250
94#endif
95
96// If the time (ms) between the last move and the release exceeds this, then velocity will be zero.
97#ifndef QML_FLICK_VELOCITY_DECAY_TIME
98#define QML_FLICK_VELOCITY_DECAY_TIME 50
99#endif
100
101// Multiflick acceleration minimum contentSize/viewSize ratio
102#ifndef QML_FLICK_MULTIFLICK_RATIO
103#define QML_FLICK_MULTIFLICK_RATIO 10
104#endif
105
106// Multiflick acceleration maximum velocity multiplier
107#ifndef QML_FLICK_MULTIFLICK_MAXBOOST
108#define QML_FLICK_MULTIFLICK_MAXBOOST 3.0
109#endif
110
111#endif //QQUICKFLICKABLEBEHAVIOR_H
112

source code of qtdeclarative/src/quick/items/qquickflickablebehavior_p.h