Qt 5.11 | Qt Widgets | Stickman Example | lifecycle.cpp Example File

Qt 5.11.3 Reference Documentation

# lifecycle.cpp Example File

animation/stickman/lifecycle.cpp

      /****************************************************************************
      **
      ** 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 "lifecycle.h"
      #include "stickman.h"
      #include "node.h"
      #include "animation.h"
      #include "graphicsview.h"

      #include <QtCore>
      #include <QtWidgets>

      class KeyPressTransition: public QSignalTransition
      {
      public:
          KeyPressTransition(GraphicsView *receiver, Qt::Key key)
              : QSignalTransition(receiver, SIGNAL(keyPressed(int))), m_key(key)
          {
          }
          KeyPressTransition(GraphicsView *receiver, Qt::Key key, QAbstractState *target)
              : QSignalTransition(receiver, SIGNAL(keyPressed(int))), m_key(key)
          {
              setTargetState(target);
          }

          bool eventTest(QEvent *e) override
          {
              if (QSignalTransition::eventTest(e)) {
                  QVariant key = static_cast<QStateMachine::SignalEvent*>(e)->arguments().at(0);
                  return (key.toInt() == int(m_key));
              }

              return false;
          }
      private:
          Qt::Key m_key;
      };

      class LightningStrikesTransition: public QEventTransition
      {
      public:
          LightningStrikesTransition(QAbstractState *target)
              : QEventTransition(this, QEvent::Timer)
          {
              setTargetState(target);
              startTimer(1000);
          }

          bool eventTest(QEvent *e) override
          {
              return QEventTransition::eventTest(e) && QRandomGenerator::global()->bounded(50) == 0;
          }
      };

      LifeCycle::LifeCycle(StickMan *stickMan, GraphicsView *keyReceiver)
          : m_stickMan(stickMan), m_keyReceiver(keyReceiver)
      {
          // Create animation group to be used for all transitions
          m_animationGroup = new QParallelAnimationGroup();
          const int stickManNodeCount = m_stickMan->nodeCount();
          for (int i=0; i<stickManNodeCount; ++i) {
              QPropertyAnimation *pa = new QPropertyAnimation(m_stickMan->node(i), "pos");
              m_animationGroup->addAnimation(pa);
          }

          // Set up initial state graph
          m_machine = new QStateMachine();
          m_machine->addDefaultAnimation(m_animationGroup);

          m_alive = new QState(m_machine);
          m_alive->setObjectName("alive");

          // Make it blink when lightning strikes before entering dead animation
          QState *lightningBlink = new QState(m_machine);
          lightningBlink->assignProperty(m_stickMan->scene(), "backgroundBrush", QColor(Qt::white));
          lightningBlink->assignProperty(m_stickMan, "penColor", QColor(Qt::black));
          lightningBlink->assignProperty(m_stickMan, "fillColor", QColor(Qt::white));
          lightningBlink->assignProperty(m_stickMan, "isDead", true);

          QTimer *timer = new QTimer(lightningBlink);
          timer->setSingleShot(true);
          timer->setInterval(100);
          QObject::connect(lightningBlink, SIGNAL(entered()), timer, SLOT(start()));
          QObject::connect(lightningBlink, SIGNAL(exited()), timer, SLOT(stop()));

          m_dead = new QState(m_machine);
          m_dead->assignProperty(m_stickMan->scene(), "backgroundBrush", QColor(Qt::black));
          m_dead->assignProperty(m_stickMan, "penColor", QColor(Qt::white));
          m_dead->assignProperty(m_stickMan, "fillColor", QColor(Qt::black));
          m_dead->setObjectName("dead");

          // Idle state (sets no properties)
          m_idle = new QState(m_alive);
          m_idle->setObjectName("idle");

          m_alive->setInitialState(m_idle);

          // Lightning strikes at random
          m_alive->addTransition(new LightningStrikesTransition(lightningBlink));
          lightningBlink->addTransition(timer, SIGNAL(timeout()), m_dead);

          m_machine->setInitialState(m_alive);
      }

      void LifeCycle::setDeathAnimation(const QString &fileName)
      {
          QState *deathAnimation = makeState(m_dead, fileName);
          m_dead->setInitialState(deathAnimation);
      }

      void LifeCycle::start()
      {
          m_machine->start();
      }

      void LifeCycle::addActivity(const QString &fileName, Qt::Key key, QObject *sender, const char *signal)
      {
          QState *state = makeState(m_alive, fileName);
          m_alive->addTransition(new KeyPressTransition(m_keyReceiver, key, state));

          if((sender != NULL) || (signal != NULL)) {
              m_alive->addTransition(sender, signal, state);
          }
      }

      QState *LifeCycle::makeState(QState *parentState, const QString &animationFileName)
      {
          QState *topLevel = new QState(parentState);

          Animation animation;
          {
              QFile file(animationFileName);
              if (file.open(QIODevice::ReadOnly))
                  animation.load(&file);
          }

          const int frameCount = animation.totalFrames();
          QState *previousState = 0;
          for (int i=0; i<frameCount; ++i) {
              animation.setCurrentFrame(i);

              QState *frameState = new QState(topLevel);
              const int nodeCount = animation.nodeCount();
              for (int j=0; j<nodeCount; ++j)
                  frameState->assignProperty(m_stickMan->node(j), "pos", animation.nodePos(j));

              frameState->setObjectName(QString::fromLatin1("frame %0").arg(i));
              if (previousState == 0)
                  topLevel->setInitialState(frameState);
              else
                  previousState->addTransition(previousState, SIGNAL(propertiesAssigned()), frameState);

              previousState = frameState;
          }

          // Loop
          previousState->addTransition(previousState, SIGNAL(propertiesAssigned()), topLevel->initialState());

          return topLevel;

      }

      LifeCycle::~LifeCycle()
      {
          delete m_machine;
          delete m_animationGroup;
      }