Overview

Support for Signals and Slots¶ One of the key features of Qt is its use of signals and slots to communicate between objects. Their use encourages the development of reusable components. A signal is emitted when something of potential interest happens. A slot is a Python callable.

This program demonstrates how QML and C++ can be connected through Qt signalsand slots. It does this through embedding C++ code as a context property in QMLrather than explicitly connecting signals and slots.

When the program is started, the C++ part send a signal to QML, including aparameter. This signal is only sent once. When the user clicks on the windowarea, a signal is sent from QML to a C++ slot.

Watch the console output to see if it works.

Installation

This program requires a working Qt5 installation. It was tested with version 5.3 and 5.4.

Signals And Slots Qt

In order to compile and run the program, execute the following commands.

Alternatively, the project can be loaded into Qt Creator and started from there.

Connect Qt Signal To Qml Slot

More Documentation

Qml Signal To C++ Slot

This source code belongs to an article on our website.