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50 | |
51 | #include <QtCore> |
52 | |
53 | //! [0] |
54 | class Factorial : public QObject |
55 | { |
56 | Q_OBJECT |
57 | Q_PROPERTY(int x READ x WRITE setX) |
58 | Q_PROPERTY(int fac READ fac WRITE setFac) |
59 | public: |
60 | using QObject::QObject; |
61 | |
62 | int x() const |
63 | { |
64 | return m_x; |
65 | } |
66 | |
67 | void setX(int x) |
68 | { |
69 | if (x == m_x) |
70 | return; |
71 | m_x = x; |
72 | emit xChanged(value: x); |
73 | } |
74 | |
75 | int fac() const |
76 | { |
77 | return m_fac; |
78 | } |
79 | |
80 | void setFac(int fac) |
81 | { |
82 | m_fac = fac; |
83 | } |
84 | |
85 | Q_SIGNALS: |
86 | void xChanged(int value); |
87 | |
88 | private: |
89 | int m_x = -1; |
90 | int m_fac = 1; |
91 | }; |
92 | //! [0] |
93 | |
94 | //! [1] |
95 | class FactorialLoopTransition : public QSignalTransition |
96 | { |
97 | public: |
98 | FactorialLoopTransition(Factorial *fact) |
99 | : QSignalTransition(fact, &Factorial::xChanged), m_fact(fact) |
100 | {} |
101 | |
102 | bool eventTest(QEvent *e) override |
103 | { |
104 | if (!QSignalTransition::eventTest(event: e)) |
105 | return false; |
106 | QStateMachine::SignalEvent *se = static_cast<QStateMachine::SignalEvent*>(e); |
107 | return se->arguments().at(i: 0).toInt() > 1; |
108 | } |
109 | |
110 | void onTransition(QEvent *e) override |
111 | { |
112 | QStateMachine::SignalEvent *se = static_cast<QStateMachine::SignalEvent*>(e); |
113 | int x = se->arguments().at(i: 0).toInt(); |
114 | int fac = m_fact->property(name: "fac" ).toInt(); |
115 | m_fact->setProperty(name: "fac" , value: x * fac); |
116 | m_fact->setProperty(name: "x" , value: x - 1); |
117 | } |
118 | |
119 | private: |
120 | Factorial *m_fact; |
121 | }; |
122 | //! [1] |
123 | |
124 | //! [2] |
125 | class FactorialDoneTransition : public QSignalTransition |
126 | { |
127 | public: |
128 | FactorialDoneTransition(Factorial *fact) |
129 | : QSignalTransition(fact, &Factorial::xChanged), m_fact(fact) |
130 | {} |
131 | |
132 | bool eventTest(QEvent *e) override |
133 | { |
134 | if (!QSignalTransition::eventTest(event: e)) |
135 | return false; |
136 | QStateMachine::SignalEvent *se = static_cast<QStateMachine::SignalEvent*>(e); |
137 | return se->arguments().at(i: 0).toInt() <= 1; |
138 | } |
139 | |
140 | void onTransition(QEvent *) override |
141 | { |
142 | qInfo() << m_fact->property(name: "fac" ).toInt(); |
143 | } |
144 | |
145 | private: |
146 | Factorial *m_fact; |
147 | }; |
148 | //! [2] |
149 | |
150 | //! [3] |
151 | int main(int argc, char **argv) |
152 | { |
153 | QCoreApplication app(argc, argv); |
154 | Factorial factorial; |
155 | QStateMachine machine; |
156 | //! [3] |
157 | |
158 | //! [4] |
159 | QState *compute = new QState(&machine); |
160 | compute->assignProperty(object: &factorial, name: "fac" , value: 1); |
161 | compute->assignProperty(object: &factorial, name: "x" , value: 6); |
162 | compute->addTransition(transition: new FactorialLoopTransition(&factorial)); |
163 | //! [4] |
164 | |
165 | //! [5] |
166 | QFinalState *done = new QFinalState(&machine); |
167 | FactorialDoneTransition *doneTransition = new FactorialDoneTransition(&factorial); |
168 | doneTransition->setTargetState(done); |
169 | compute->addTransition(transition: doneTransition); |
170 | //! [5] |
171 | |
172 | //! [6] |
173 | machine.setInitialState(compute); |
174 | QObject::connect(sender: &machine, signal: &QStateMachine::finished, context: &app, slot: QCoreApplication::quit); |
175 | machine.start(); |
176 | |
177 | return app.exec(); |
178 | } |
179 | //! [6] |
180 | |
181 | #include "main.moc" |
182 | |