We do not recommend holding pointers to child objects from outside the parent. If a signal is connected to several slots, the slots are activated in the same order as the order the connection was made, when the signal is emitted The function returns an handle to a connection if it successfully connects the signal to the slot.
The Connection handle will be invalid if it cannot create the connection, for example, if QObject is unable to verify the existence of signal if it was not declared as a signal You can check if the QMetaObject:: The signal must be a function declared as a signal in the header.
Equivalent to connect sender, signal, this, method, type. For every child widget, you receive one ChildAdded event, zero or more ChildPolished events, and one ChildRemoved event.
Returns true if the connection is successfully broken; otherwise returns false. You can break all of these connections with a single disconnect call. This function was introduced in Qt 4. AutoConnection This function overloads connect. However, you should take care that any objects used within the functor are still alive when the signal is emitted.
If the object is a widget, it will become a top-level window. See also parentfindChildand findChildren.
QueuedConnection ; Lambda expressions can also be used: Disconnect everything connected to an object's signals: See also event and QEvent. The parent of an object may be viewed as the object's owner.
The function returns a QMetaObject:: If you try to use a queued connection and get the error message QObject:: If a child is polished several times during construction and destruction, you may receive several child polished events for the same child, each time with a different virtual table. AutoConnection ; The connection will automatically disconnect if the sender or the context is destroyed.
UniqueConnections do not work for lambdas, non-member functions and functors; they only apply to connecting to member functions.