link errors in tester

1>Linking...
1>Tester.obj : error LNK2001: unresolved external symbol "public: virtual struct QMetaObject const * __thiscall Tester::metaObject(void)const " (?metaObject@Tester@@UBEPBUQMetaObject@@XZ)
1>Tester.obj : error LNK2001: unresolved external symbol "public: virtual void * __thiscall Tester::qt_metacast(char const *)" (?qt_metacast@Tester@@UAEPAXPBD@Z)
1>Tester.obj : error LNK2001: unresolved external symbol "public: virtual int __thiscall Tester::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@Tester@@UAEHW4Call@QMetaObject@@HPAPAX@Z)
1>Debug/Tester.exe : fatal error LNK1120: 3 unresolved externals