lifecycle.cpp Example File
animation/stickman/lifecycle.cpp

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

 #include <QtCore>
 #include <QtGui>

 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)
     {
         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)
     {
         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 intial 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", Qt::white);
     lightningBlink->assignProperty(m_stickMan, "penColor", Qt::black);
     lightningBlink->assignProperty(m_stickMan, "fillColor", 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", Qt::black);
     m_dead->assignProperty(m_stickMan, "penColor", Qt::white);
     m_dead->assignProperty(m_stickMan, "fillColor", 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)
 {
     QState *state = makeState(m_alive, fileName);
     m_alive->addTransition(new KeyPressTransition(m_keyReceiver, key, 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;
 }