c++ - Qt-没有匹配函数可调用以进行连接

尝试致电connect时出现此错误。



我在graphscene.cpp中称为connect

    GraphScene::GraphScene(QObject *parent) : QGraphicsScene (parent), mode(NAV) {
        QObject::connect(parent, &MainWindow::changedMode, this, &GraphScene::setMode);
    }

GraphScene类:

class GraphScene : public QGraphicsScene {
    Q_OBJECT
public:
    GraphScene(QObject *);
    void mousePressEvent(QGraphicsSceneMouseEvent*);

public slots:
    void setMode(Mode m);

private:
    Mode mode;
}

MainWindow类:

class MainWindow : public QMainWindow {
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

public slots:
    void actionTriggered(QAction *action);

signals:
    void changedMode(Mode newMode);

private:
    Ui::MainWindow *ui;
    QActionGroup* modesGroup;
    GraphScene *scene;
};

我在这里发出信号，我不知道是否与信号有关:

 void MainWindow::actionTriggered(QAction *action){
    QString actionText = action->text() ;
    if(actionText == "Navigation"){
        emit changedMode(NAV);
    }
    else if (actionText == "Add node") {
        emit changedMode(ADD_NODE);
    }
    else if (actionText == "Delete node") {
        emit changedMode(DEL_NODE);
    }
}

我找到了许多其他与SO相关的答案，但无法解决。大多数告诉检查QObject继承和Q_OBJECT宏。

最佳答案

您是否尝试过将MainWindow*发送到ctor？我认为它无法将sender函数映射到其对象:

GraphScene::GraphScene(MainWindow *parent)
    : QGraphicsScene (parent), mode(NAV)
{
    QObject::connect(parent, &MainWindow::changedMode, this, &GraphScene::setMode);
}