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39
40#include "qquickparticlegroup_p.h"
41
42/*!
43 \qmltype ParticleGroup
44 \instantiates QQuickParticleGroup
45 \inqmlmodule QtQuick.Particles
46 \brief For setting attributes on a logical particle group.
47 \ingroup qtquick-particles
48
49 This element allows you to set timed transitions on particle groups.
50
51 You can also use this element to group particle system elements related to the logical
52 particle group. Emitters, Affectors and Painters set as direct children of a ParticleGroup
53 will automatically apply to that logical particle group. TrailEmitters will automatically follow
54 the group.
55
56 If a ParticleGroup element is not defined for a group, the group will function normally as if
57 none of the transition properties were set.
58*/
59/*!
60 \qmlproperty ParticleSystem QtQuick.Particles::ParticleGroup::system
61 This is the system which will contain the group.
62
63 If the ParticleGroup is a direct child of a ParticleSystem, it will automatically be associated with it.
64*/
65/*!
66 \qmlproperty string QtQuick.Particles::ParticleGroup::name
67 This is the name of the particle group, and how it is generally referred to by other elements.
68
69 If elements refer to a name which does not have an explicit ParticleGroup created, it will
70 work normally (with no transitions specified for the group). If you do not need to assign
71 duration based transitions to a group, you do not need to create a ParticleGroup with that name (although you may).
72*/
73/*!
74 \qmlproperty int QtQuick.Particles::ParticleGroup::duration
75 The time in milliseconds before the group will attempt to transition.
76
77*/
78/*!
79 \qmlproperty ParticleSystem QtQuick.Particles::ParticleGroup::durationVariation
80 The maximum number of milliseconds that the duration of the transition cycle varies per particle in the group.
81
82 Default value is zero.
83*/
84/*!
85 \qmlproperty ParticleSystem QtQuick.Particles::ParticleGroup::to
86 The weighted list of transitions valid for this group.
87
88 If the chosen transition stays in this group, another duration (+/- up to durationVariation)
89 milliseconds will occur before another transition is attempted.
90*/
91
92QQuickParticleGroup::QQuickParticleGroup(QObject* parent)
93 : QQuickStochasticState(parent)
94 , m_system(nullptr)
95{
96
97}
98
99void delayedRedirect(QQmlListProperty<QObject> *prop, QObject *value)
100{
101 QQuickParticleGroup* pg = qobject_cast<QQuickParticleGroup*>(object: prop->object);
102 if (pg)
103 pg->delayRedirect(obj: value);
104}
105
106QQmlListProperty<QObject> QQuickParticleGroup::particleChildren()
107{
108 QQuickParticleSystem* system = qobject_cast<QQuickParticleSystem*>(object: parent());
109 if (system) {
110 return QQmlListProperty<QObject>(this, nullptr,
111 &QQuickParticleSystem::statePropertyRedirect, nullptr,
112 nullptr, nullptr, nullptr, nullptr);
113 } else {
114 return QQmlListProperty<QObject>(this, nullptr,
115 &delayedRedirect, nullptr, nullptr,
116 nullptr, nullptr, nullptr);
117 }
118}
119
120void QQuickParticleGroup::setSystem(QQuickParticleSystem* arg)
121{
122 if (m_system != arg) {
123 m_system = arg;
124 m_system->registerParticleGroup(g: this);
125 performDelayedRedirects();
126 emit systemChanged(arg);
127 }
128}
129
130void QQuickParticleGroup::delayRedirect(QObject *obj)
131{
132 m_delayedRedirects << obj;
133}
134
135void QQuickParticleGroup::performDelayedRedirects()
136{
137 if (!m_system)
138 return;
139 foreach (QObject* obj, m_delayedRedirects)
140 m_system->stateRedirect(group: this, sys: m_system, value: obj);
141
142 m_delayedRedirects.clear();
143}
144
145void QQuickParticleGroup::componentComplete(){
146 if (!m_system && qobject_cast<QQuickParticleSystem*>(object: parent()))
147 setSystem(qobject_cast<QQuickParticleSystem*>(object: parent()));
148}
149
150#include "moc_qquickparticlegroup_p.cpp"
151

source code of qtdeclarative/src/particles/qquickparticlegroup.cpp