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在我的代码中，我有McdGraphicsScene继承自的类QGraphicsScene，但是当我尝试将指针传递给 to 的实例时，McdGraphicsScene出现QGraphicsView::setScene(QGraphicsScene* scene);以下错误：

../MeriseModeler/merisemodeler/mcdui.cpp: In member function 'void McdUi::setModel(McdModel*)':
../MeriseModeler/merisemodeler/mcdui.cpp:34:42: error: no matching function for call to 'QGraphicsView::setScene(McdGraphicsScene*)'
../MeriseModeler/merisemodeler/mcdui.cpp:34:42: note: candidate is:
In file included from ../../.qt5/5.0.0/gcc/include/QtWidgets/QGraphicsView:1:0,
                 from ../MeriseModeler/merisemodeler/mcdui.cpp:10:
../../.qt5/5.0.0/gcc/include/QtWidgets/qgraphicsview.h:161:10: note: void QGraphicsView::setScene(QGraphicsScene*)
../../.qt5/5.0.0/gcc/include/QtWidgets/qgraphicsview.h:161:10: note:   no known conversion for argument 1 from 'McdGraphicsScene*' to 'QGraphicsScene*'

这是类的代码

class McdGraphicsScene : public QGraphicsScene
{
    Q_OBJECT

    // Methods and attributs
};
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1 回答 1

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您是否使用任何前向声明McdGraphicsScene？

确保实际的类定义在调用站点可见。如果只有前向声明可用，则调用代码无法推断出McdGraphicsScene继承自QGraphicsScene.

于 2013-03-06T12:35:31.653 回答