Top "Signals-slots" questions

Signals and slots is a mechanism for implementing the observer pattern.

Argument type for Qt signal and slot, does const reference qualifiers matters?

For signal and slot of below type signals: void textChanged(const QString &); public slots: void setText(const QString & …

qt connection types arguments signals-slots
Does it make any difference, using public slots instead of private slots in Qt?

In C++, public means those members that are accessible from anywhere where the object is visible, private means that members …

c++ qt signals-slots
How to perform action on clicking a QMenu object only?

Here's a snapshot of the GUI. I want to perform simple actions solely by clicking on QMenu object Help. This …

qt signals-slots qmenu qaction
const-ref when sending signals in Qt

This is a thing that I never quite got with const-ref and I really hope that someone could explain it …

c++ qt signals-slots const-reference pass-by-const-reference
What are signals and slots?

Can someone explain in simple terms the "signals and slots" pattern?

c++ design-patterns signals-slots
How to connect a QSlider to QDoubleSpinBox

I want to connect a QSlider to a QDoubleSpinBox but while the code compiles fine and runs for simple QSpinBox, …

qt connect signals-slots qslider
How to pass variables to slot methods in QT?

I'm making a little chat messenger program, which needs a list of chat channels the user has joined. To represent …

c++ qt signals-slots
Does large use of signals and slots affect application performance?

The question is just done for educational purpose: Does the use of 30-50 or more pairs of signals and slots …

qt signals-slots
Is it possible to create a signal for when a QTreeWidgetItem checkbox is toggled?

I've created a checkbox that's also a QTreeWidgetItem using the code below. //Populate list QTreeWidgetItem *program = createCheckedTreeItem(QString::fromStdString(itr-&…

c++ qt checkbox signals-slots qtreewidgetitem
Separate user interaction from programmical change: PyQt, QComboBox

I have several QComboBoxes in my PyQt4/Python3 GUI and they are filled with some entries from a database during …

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