QT 关联QComboBox的currentIndexChanged时遇到 成员指针指向重载指针函数问题

在项目中动态添加了一个QComboBox,在当准备关联currentIndexChanged信号到某个成员函数中时,发现currentIndexChanged有两个重载:

    void currentIndexChanged(int index);
    void currentIndexChanged(const QString &);

如果直接关联，例:

connect(comboBox, &QComboBox::currentIndexChanged,this,  &Dialog::comBoxChangeIndex);

　会报:

error: no matching member function for call to 'connect'

需要把对应的函数强转一下，指定使用currentIndexChanged函数的那个重载:

connect(comboBox, (void (QComboBox::*)(int))&QComboBox::currentIndexChanged, this, (void (Dialog::*)(int))&Dialog::comBoxChangeIndex);

connect(comboBox, (void (QComboBox::*)(int))&QComboBox::currentIndexChanged, this, (void (Dialog::*)(int))&Dialog::comBoxChangeIndex);

这样，就指定了要用QComboBox的currentIndexChanged(int)重载,如果想使用currentIndexChanged(const QString &)重载,把(void (QComboBox::*)(int))改成(void (QComboBox::*)(const QString &))

例:

  connect(combobox, (void (QComboBox::*)(int))&QComboBox::currentIndexChanged, this, (void (Setting::*)(int))&Setting::typeComBoxCurrentIndexChanged);
  connect(combobox, (void (QComboBox::*)(const QString &))&QComboBox::currentIndexChanged, this, (void (Setting::*)(QString))&Setting::typeComBoxCurrentIndexChanged);

这里Setting类的typeComBoxCurrentIndexChanged函数也有两个重载，对应QComboBox的currentIndexChanged函数两个重载。

void typeComBoxCurrentIndexChanged(int)
void typeComBoxCurrentIndexChanged(QString)