今天我看到了这段代码:
void CameraTree::dragMoveEvent(QDragMoveEvent *event)
{
QTreeWidget:dragMoveEvent(event);
}
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我认为上面的代码是错误的.但:
void CameraTree::dragMoveEvent(QDragMoveEvent *event)
{
dragMoveEvent(event);//infinite recursion???
}
void CameraTree::dragMoveEvent(QDragMoveEvent *event)
{
QTreeWidget::dragMoveEvent(event);
// I understand is called dragMoveEvent in class QTreeWidget.
// But dragMoveEvent is not static??
}
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并且只警告"未使用的标签QTreeWidget",编译成功.什么:意思?
我尝试创建一个宏来定义X,但08和09被编译器误解为杂散运算符.当其他人工作正常时,为什么这些失败?
#define LIST_TEST_X \
X(A,01)\
X(B,02)\
X(C,03)\
X(D,04)\
X(E,05)\
X(F,06)\
X(G,07)\
X(H,08)\
X(I,09)\
X(K,10)
enum XEnum
{
#define X(A, b) A=b,
LIST_TEST_X
#undef X
};
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