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huangaoliu

请问 我用QT   
我在自己的类中想有自己的slot  我在类中加入 Q_OBJECT 这句话

为什么编译错误？？
错误提升如下：
.obj/mp3.o(.text+0x33): In function
`Mywidget::Mywidget[not-in-charge](QWidget*, char
const*)':
/home/adam/mp3.cpp:22: undefined reference to `vtable
for Mywidget'
.obj/mp3.o(.text+0x3f):/home/adam/mp3.cpp:22:
undefined reference to `vtable for Mywidget'
.obj/mp3.o(.text+0x903): In function
`Mywidget::Mywidget[in-charge](QWidget*, char
const*)':
/home/adam/mp3.cpp:22: undefined reference to `vtable
for Mywidget'
.obj/mp3.o(.text+0x90f):/home/adam/mp3.cpp:22:
undefined reference to `vtable for Mywidget'
.obj/mp3.o(.text+0x131a): In function `main':
/home/adam/mp3.cpp:83: undefined reference to `vtable
for Mywidget'
.obj/mp3.o(.text+0x1325):/home/adam/mp3.cpp:83: more
undefined references to `vtable for Mywidget' follow
collect2: ld returned 1 exit status
make: *** [mp3] 错误 1

在线等 急！！