lifecycle.cpp Example File

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  #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);
      }

      virtual bool eventTest(QEvent *e) Q_DECL_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);
          qsrand((uint)QDateTime::currentDateTime().toTime_t());
          startTimer(1000);
      }

      virtual bool eventTest(QEvent *e) Q_DECL_OVERRIDE
      {
          return QEventTransition::eventTest(e) && ((qrand() % 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;
  }