无响应的QGraphicsPixmapItem keyPressEvent

Question

我在尝试实现一个基本的游戏..。

我按键盘按钮，但我添加到我的QGraphicsPixmapItem QGraphicsScene不移动，我已经实现了一个keyPressedEvent函数.

当按下键时，我想移动像素映射项。

代码在下面..。

H(我的像素映射项的头文件)

 class marioChar : public QObject, public QGraphicsPixmapItem
{
Q_OBJECT
public:
    bool flying;
    explicit marioChar(QPixmap pic);
    void keyPressEvent(QKeyEvent *event);

signals:

public slots:
 };

这是keypressEvent处理程序的实现：

   void marioChar::keyPressEvent(QKeyEvent *event)
{
    if(event->key()==Qt::Key_Right)
    {
        if(x()<380)
        {
            this->setPos(this->x()+20,this->y());
        }
    }
}

This is part of the game class where i add the pixmap item to the scene



game::game(int difficulty_Level)
{

       set_Level(difficulty_Level);
       set_Num_Of_Coins(0);
       set_Score(0);
       QGraphicsScene *scene = new QGraphicsScene();
       header = new QGraphicsTextItem();
       header->setZValue(1000);
       timer = new QTimer();
       time = new QTime();
       time->start();
       updateDisplay();
       scene->addItem(header);

       connect(timer,SIGNAL(timeout()),this,SLOT(updateDisplay()));
       timer->start(500);

       QGraphicsView *view = new QGraphicsView(scene);
       scene->setSceneRect(0,0,1019,475);

       QColor skyBlue;
       skyBlue.setRgb(135,206,235);
       view->setBackgroundBrush(QBrush(skyBlue));

       QGraphicsRectItem *floor = new QGraphicsRectItem(0,460,1024,20);
       floor->setBrush(Qt::black);
       scene->addItem(floor);

       player= new marioChar(QPixmap("MarioF.png"));
       player->setPos(0,330);
       player->setZValue(1003);
       scene->addItem(player);

       view->setFixedSize(1024,480);
       view->show();
       player->setFocus();
    }

提前感谢

Answer 1

如果希望图形项侦听关键事件，则需要将QGraphicsItem::ItemIsFocusable标志设置为图形项。

从医生那里：

http://doc.qt.io/qt-5/qgraphicsitem.html#keyPressEvent

以及对QGraphicsItem::ItemIsFocusable标志的描述：

http://qt-project.org/doc/qt-4.8-snapshot/qgraphicsitem.html#GraphicsItemFlag-enum

Answer 2

您的QGraphicsPixmapItem不应该继承QObject。您应该创建一个控制器来管理您的QGraphicsPixmapItem，并发出信号并处理游戏中所有QGraphicsPixmapItem的插槽。

Answer 3

如前所述：“将QGraphicsItem::ItemIsFocusable标志设置为您的marioChar对象”