| /**************************************************************************** |
| ** |
| ** Copyright (C) 2016 The Qt Company Ltd. |
| ** Contact: https://www.qt.io/licensing/ |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:BSD$ |
| ** Commercial License Usage |
| ** Licensees holding valid commercial Qt licenses may use this file in |
| ** accordance with the commercial license agreement provided with the |
| ** Software or, alternatively, in accordance with the terms contained in |
| ** a written agreement between you and The Qt Company. For licensing terms |
| ** and conditions see https://www.qt.io/terms-conditions. For further |
| ** information use the contact form at https://www.qt.io/contact-us. |
| ** |
| ** BSD License Usage |
| ** Alternatively, you may use this file under the terms of the BSD license |
| ** as follows: |
| ** |
| ** "Redistribution and use in source and binary forms, with or without |
| ** modification, are permitted provided that the following conditions are |
| ** met: |
| ** * Redistributions of source code must retain the above copyright |
| ** notice, this list of conditions and the following disclaimer. |
| ** * Redistributions in binary form must reproduce the above copyright |
| ** notice, this list of conditions and the following disclaimer in |
| ** the documentation and/or other materials provided with the |
| ** distribution. |
| ** * Neither the name of The Qt Company Ltd nor the names of its |
| ** contributors may be used to endorse or promote products derived |
| ** from this software without specific prior written permission. |
| ** |
| ** |
| ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #include <QApplication> |
| #include <QFinalState> |
| #include <QPainter> |
| #include <QStateMachine> |
| #include <QTimer> |
| #include <QVBoxLayout> |
| #include <QWidget> |
| |
| //! [0] |
| class LightWidget : public QWidget |
| { |
| Q_OBJECT |
| Q_PROPERTY(bool on READ isOn WRITE setOn) |
| public: |
| LightWidget(const QColor &color, QWidget *parent = nullptr) |
| : QWidget(parent), m_color(color), m_on(false) {} |
| |
| bool isOn() const |
| { return m_on; } |
| void setOn(bool on) |
| { |
| if (on == m_on) |
| return; |
| m_on = on; |
| update(); |
| } |
| |
| public slots: |
| void turnOff() { setOn(false); } |
| void turnOn() { setOn(true); } |
| |
| protected: |
| void paintEvent(QPaintEvent *) override |
| { |
| if (!m_on) |
| return; |
| QPainter painter(this); |
| painter.setRenderHint(QPainter::Antialiasing); |
| painter.setBrush(m_color); |
| painter.drawEllipse(0, 0, width(), height()); |
| } |
| |
| private: |
| QColor m_color; |
| bool m_on; |
| }; |
| //! [0] |
| |
| //! [1] |
| class TrafficLightWidget : public QWidget |
| { |
| public: |
| TrafficLightWidget(QWidget *parent = nullptr) |
| : QWidget(parent) |
| { |
| QVBoxLayout *vbox = new QVBoxLayout(this); |
| m_red = new LightWidget(Qt::red); |
| vbox->addWidget(m_red); |
| m_yellow = new LightWidget(Qt::yellow); |
| vbox->addWidget(m_yellow); |
| m_green = new LightWidget(Qt::green); |
| vbox->addWidget(m_green); |
| QPalette pal = palette(); |
| pal.setColor(QPalette::Window, Qt::black); |
| setPalette(pal); |
| setAutoFillBackground(true); |
| } |
| |
| LightWidget *redLight() const |
| { return m_red; } |
| LightWidget *yellowLight() const |
| { return m_yellow; } |
| LightWidget *greenLight() const |
| { return m_green; } |
| |
| private: |
| LightWidget *m_red; |
| LightWidget *m_yellow; |
| LightWidget *m_green; |
| }; |
| //! [1] |
| |
| //! [2] |
| QState *createLightState(LightWidget *light, int duration, QState *parent = nullptr) |
| { |
| QState *lightState = new QState(parent); |
| QTimer *timer = new QTimer(lightState); |
| timer->setInterval(duration); |
| timer->setSingleShot(true); |
| QState *timing = new QState(lightState); |
| QObject::connect(timing, &QAbstractState::entered, light, &LightWidget::turnOn); |
| QObject::connect(timing, &QAbstractState::entered, timer, QOverload<>::of(&QTimer::start)); |
| QObject::connect(timing, &QAbstractState::exited, light, &LightWidget::turnOff); |
| QFinalState *done = new QFinalState(lightState); |
| timing->addTransition(timer, &QTimer::timeout, done); |
| lightState->setInitialState(timing); |
| return lightState; |
| } |
| //! [2] |
| |
| //! [3] |
| class TrafficLight : public QWidget |
| { |
| public: |
| TrafficLight(QWidget *parent = nullptr) |
| : QWidget(parent) |
| { |
| QVBoxLayout *vbox = new QVBoxLayout(this); |
| TrafficLightWidget *widget = new TrafficLightWidget; |
| vbox->addWidget(widget); |
| vbox->setContentsMargins(QMargins()); |
| |
| QStateMachine *machine = new QStateMachine(this); |
| QState *redGoingYellow = createLightState(widget->redLight(), 3000); |
| redGoingYellow->setObjectName("redGoingYellow"); |
| QState *yellowGoingGreen = createLightState(widget->yellowLight(), 1000); |
| yellowGoingGreen->setObjectName("yellowGoingGreen"); |
| redGoingYellow->addTransition(redGoingYellow, &QState::finished, yellowGoingGreen); |
| QState *greenGoingYellow = createLightState(widget->greenLight(), 3000); |
| greenGoingYellow->setObjectName("greenGoingYellow"); |
| yellowGoingGreen->addTransition(yellowGoingGreen, &QState::finished, greenGoingYellow); |
| QState *yellowGoingRed = createLightState(widget->yellowLight(), 1000); |
| yellowGoingRed->setObjectName("yellowGoingRed"); |
| greenGoingYellow->addTransition(greenGoingYellow, &QState::finished, yellowGoingRed); |
| yellowGoingRed->addTransition(yellowGoingRed, &QState::finished, redGoingYellow); |
| |
| machine->addState(redGoingYellow); |
| machine->addState(yellowGoingGreen); |
| machine->addState(greenGoingYellow); |
| machine->addState(yellowGoingRed); |
| machine->setInitialState(redGoingYellow); |
| machine->start(); |
| } |
| }; |
| //! [3] |
| |
| //! [4] |
| int main(int argc, char **argv) |
| { |
| QApplication app(argc, argv); |
| |
| TrafficLight widget; |
| widget.resize(110, 300); |
| widget.show(); |
| |
| return app.exec(); |
| } |
| //! [4] |
| |
| #include "main.moc" |