Creating and deallocating a Qt widget object

Question

I heard that the widgets should be allocated on the heap (using new), and then there are no needs to delete them (it is done automatically).

1. Can someone explai

Answer 1

There's no magic involved. Simply put, a QObject automatically deletes its children in its destructor. So, as long as your widget has a parent and that you destroy that parent, you don't have to worry about the children. So if you wondered what was that QObject * parent parameter, well, that's what it's there for.

Also, from the doc:

All child objects are deleted. If any of these objects are on the stack or global, sooner or later your program will crash.

So, avoid giving parents to objects that are stack-allocated.