Loose coupling: The key advantage of the signals and slots is that the caller does not have to know anything about the receiver and vice versa. Only connect the signals you need, while in a listener you need to implement also the methods you won't use. The virtual folder exists so that we do not have to specify absolute links. You can call the namespace and virtual folder whatever you like but afterward, you have to remain consistent with your choices. The virtual folder cannot contain any '/'. Walletfox.qt.helpexample doc.

Overview

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.

Virtual Slots Online

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

Qt Signal Slot

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

More Documentation

Qt Connect Signal Slot

This source code belongs to an article on our website.