qt多个cpp文件使用同一个对象transdata,参照https://bbs.csdn.net/topics/391995068在transdata.h里声明extren TRANSDATA transdata。在a.h里#include "transdata.h",编译正常,使用transdata正常。在mainwindow.h里#include "transdata.h",使用transdata编译报错error: undefined reference to `transdata',
transdata.h
class TRANSDATA : public QObject{
int m_a = 0;
...}
extern TRANSDATA transdata;
a.h
#include "transdata.h"
a.cpp
qDebug()<<transdata.m_a;
mainwindow.h
#include "transdata.h"
mainwindow.cpp
qDebug()<<transdata.m_a; //编译报错error: undefined reference to `transdata',
请教,代码改如何修改呢