New signals should only be defined in sub-classes of Note that because we use a string to specify the type of # the QString argument then this code will run under Python v2 and v3. range_changed = pyqtSignal ( int, int, name = 'rangeChanged' ) # This defines a signal called 'valueChanged' that has two overloads, # one that takes an integer argument and one that takes a QString # argument.

closed = pyqtSignal () # This defines a signal called 'rangeChanged' that takes two # integer arguments. The following example shows the definition of a number of new signals:įrom PyQt5.QtCore import QObject, pyqtSignal class Foo ( QObject ): # This defines a signal called 'closed' that takes no arguments.

This may only be given as a keyword argument. arguments - the sequence of the names of the signal's arguments that is exported to.revision - the revision of the signal that is exported to QML.If it is omitted then the name of the classĪttribute is used. In this caseĮach sequence defines the signature of a different signal overload. Each type mayīe a Python type object or a string that is the name of a C++ type.Īlternatively each may be a sequence of type arguments. types - the types that define the C++ signature of the signal.pyqtSignal ( types ] ] ] ) ¶Ĭreate one or more overloaded unbound signals as a class attribute. New signalsĬan be defined as class attributes using the pyqtSignal()įactory. PyQt5 automatically defines signals for all Qt's built-in signals. System while ensuring that its reference count is properly maintained. Wrapped in a special C++ type that allows it to be passed around Qt's meta-type If an argument doesn't have a corresponding C++ type then it is When a signal is emitted then any arguments are converted to C++ types if If a signal is overloaded then it will have a default that will be used if no Used instead of the non-normalised const QVariant &. The name of aĬ++ type is automatically normalised so that, for example, QVariant can be A type is eitherĪ Python type object or a string that is the name of a C++ type. A signal may be indexed with a signature in order to

a signal with a particular name may support That is the signature of the signal that would be returned by Qt's SIGNAL()Ī signal may be overloaded, ie. This is the same mechanism that Python itself uses to create boundĪ bound signal has connect(), disconnect() and emit() methods that Is referenced as an attribute of an instance of the class then PyQt5Īutomatically binds the instance to the signal in order to create a bound A signal (specifically an unbound signal) is a class attribute.

Qt one signal to multiple slots order