Object::connect: No such slot QWidget::

出现如下错误

Object::connect: No such slot QWidget::readMyCom() in ../untitled/ConversionScreen.cpp:49

解决办法
加入Q_OBJECT。使当前类具有信号槽的能力

class ConversionScreen : public QWidget
{
    Q_OBJECT

 public:
     explicit ConversionScreen(QWidget *parent = 0);
     ~ConversionScreen();

private slots:
    void on_pushButton_clicked();
    void readMyCom();
};