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50
51#include <QtCore>
52#include <stdio.h>
53
54//! [0]
55class PingEvent : public QEvent
56{
57public:
58 PingEvent() : QEvent(QEvent::Type(QEvent::User+2))
59 {}
60};
61
62class PongEvent : public QEvent
63{
64public:
65 PongEvent() : QEvent(QEvent::Type(QEvent::User+3))
66 {}
67};
68//! [0]
69
70//! [1]
71class Pinger : public QState
72{
73public:
74 Pinger(QState *parent)
75 : QState(parent) {}
76
77protected:
78 void onEntry(QEvent *) override
79 {
80 machine()->postEvent(event: new PingEvent());
81 fprintf(stdout, format: "ping?\n");
82 }
83};
84//! [1]
85
86//! [3]
87class PongTransition : public QAbstractTransition
88{
89public:
90 PongTransition() {}
91
92protected:
93 bool eventTest(QEvent *e) override {
94 return (e->type() == QEvent::User+3);
95 }
96 void onTransition(QEvent *) override
97 {
98 machine()->postDelayedEvent(event: new PingEvent(), delay: 500);
99 fprintf(stdout, format: "ping?\n");
100 }
101};
102//! [3]
103
104//! [2]
105class PingTransition : public QAbstractTransition
106{
107public:
108 PingTransition() {}
109
110protected:
111 bool eventTest(QEvent *e) override {
112 return (e->type() == QEvent::User+2);
113 }
114 void onTransition(QEvent *) override
115 {
116 machine()->postDelayedEvent(event: new PongEvent(), delay: 500);
117 fprintf(stdout, format: "pong!\n");
118 }
119};
120//! [2]
121
122//! [4]
123int main(int argc, char **argv)
124{
125 QCoreApplication app(argc, argv);
126
127 QStateMachine machine;
128 QState *group = new QState(QState::ParallelStates);
129 group->setObjectName("group");
130//! [4]
131
132//! [5]
133 Pinger *pinger = new Pinger(group);
134 pinger->setObjectName("pinger");
135 pinger->addTransition(transition: new PongTransition());
136
137 QState *ponger = new QState(group);
138 ponger->setObjectName("ponger");
139 ponger->addTransition(transition: new PingTransition());
140//! [5]
141
142//! [6]
143 machine.addState(state: group);
144 machine.setInitialState(group);
145 machine.start();
146
147 return app.exec();
148}
149//! [6]
150

source code of qtbase/examples/widgets/statemachine/pingpong/main.cpp