QT connect, signal, slot and lambda comparison

No simple information , Mainly talk about the differences , The first conclusion is Recommend to use lambda Format binding signal slot , Personal view , There are other suggestions welcome to discuss , The specific reasons are as follows ：

1. SIGNAL,SLOT yes Qt4 Method of time , lambda yes Qt5 Introduced . The new is better than the old ~(￣▽￣)~*
2. SIGNAL(sig()) Equivalent to "2sig()", SLOT(slot()) Equivalent to "1slot()", They are Qt The macro , Just one. c Format string , Cannot type check a signal slot at compile time ; and lambda use &Class::func Bind the signal slot in the form of function pointer , You can do type checking at compile time （￣︶￣）
3. SIGNAL,SLOT Function parameters in are not recommended const, & And so on , Spaces between parameters are not recommended , but clang-formate Spaces will be automatically added between parameters , So there will always be similar warnings o(≧ mouth ≦)o Signature is not normalized. Use checkUpdates(QUrl,QString) instead of checkUpdates(const QUrl &, const QString &) [clazy-connect-not-normalized]
4. lambda When Binding overloaded functions , Specify parameter type method ：QOverload<int>(&QButtonGroup::buttonClicked)