Question

我正在尝试实施基本游戏......

我按键盘按钮，但我添加到QGraphicsScene的QGraphicsPixmapItem 我没有动，我已经实现了一个keyPressedEvent函数......

我想在按下某个键时移动像素图项目。

代码在下面......

marioChar.h（我的pixmap项目的头文件）

 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();
    }

提前致谢

Answer 1

如果您希望它监听关键事件，您需要将QGraphicsItem::ItemIsFocusable标志设置为图形项目。

来自文档：

Note that key events are only received for items that set the ItemIsFocusable flag, and that have keyboard input focus.

QGraphicsItem::ItemIsFocusable标志的描述：

The item supports keyboard input focus (i.e., it is an input item). Enabling this flag will allow the item to accept focus, which again allows the delivery of key events to QGraphicsItem::keyPressEvent() and QGraphicsItem::keyReleaseEvent().

Answer 2

您的QGraphicsPixmapItem不应继承QObject。您应该创建一个管理QGraphicsPixmapItem的控制器，并发出信号并处理游戏中所有QGraphicsPixmapItem的插槽。

Answer 3

正如thuga所说：＆＃34;将QGraphicsItem :: ItemIsFocusable标志设置为marioChar对象＆＃34;

QGraphicsPixmapItem具有无响应的keyPressEvent

3 个答案: