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50
51#include <QApplication>
52#include <QEventTransition>
53#include <QPushButton>
54#include <QStateMachine>
55#include <QVBoxLayout>
56#include <QWidget>
57
58//! [0]
59class Window : public QWidget
60{
61public:
62 Window(QWidget *parent = nullptr)
63 : QWidget(parent)
64 {
65 QPushButton *button = new QPushButton(this);
66 button->setSizePolicy(hor: QSizePolicy::Expanding, ver: QSizePolicy::Expanding);
67
68 QVBoxLayout *layout = new QVBoxLayout;
69 layout->addWidget(button);
70 layout->setContentsMargins(left: 80, top: 80, right: 80, bottom: 80);
71 setLayout(layout);
72//! [0]
73
74//! [1]
75 QStateMachine *machine = new QStateMachine(this);
76
77 QState *s1 = new QState();
78 s1->assignProperty(object: button, name: "text", value: "Outside");
79
80 QState *s2 = new QState();
81 s2->assignProperty(object: button, name: "text", value: "Inside");
82//! [1]
83
84//! [2]
85 QEventTransition *enterTransition = new QEventTransition(button, QEvent::Enter);
86 enterTransition->setTargetState(s2);
87 s1->addTransition(transition: enterTransition);
88//! [2]
89
90//! [3]
91 QEventTransition *leaveTransition = new QEventTransition(button, QEvent::Leave);
92 leaveTransition->setTargetState(s1);
93 s2->addTransition(transition: leaveTransition);
94//! [3]
95
96//! [4]
97 QState *s3 = new QState();
98 s3->assignProperty(object: button, name: "text", value: "Pressing...");
99
100 QEventTransition *pressTransition = new QEventTransition(button, QEvent::MouseButtonPress);
101 pressTransition->setTargetState(s3);
102 s2->addTransition(transition: pressTransition);
103
104 QEventTransition *releaseTransition = new QEventTransition(button, QEvent::MouseButtonRelease);
105 releaseTransition->setTargetState(s2);
106 s3->addTransition(transition: releaseTransition);
107//! [4]
108
109//! [5]
110 machine->addState(state: s1);
111 machine->addState(state: s2);
112 machine->addState(state: s3);
113
114 machine->setInitialState(s1);
115 machine->start();
116 }
117};
118//! [5]
119
120//! [6]
121int main(int argc, char **argv)
122{
123 QApplication app(argc, argv);
124 Window window;
125 window.resize(w: 300, h: 300);
126 window.show();
127
128 return app.exec();
129}
130//! [6]
131

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