Skip to content
Extended properties for Qt5
C++ QMake Yacc Other
Branch: master
Clone or download

Build Status


This is user and programmist friendly properties for Qt framework. See wiki for some details.


There are some limitations of standard Qt property system. This project is an attempt to make better properties. The key features are:

  • Properties hierarchy (properties can be organized in hierarchy at any depth)
  • Property widget to observe and edit properties in uniform way
  • Signals before and after property has changed
  • Property description - short text which help user to understand meaning and purpose of the property
  • Property state - property can be disabled or hidden at any moment
  • Serialization via QDataStream
  • Set/Get property value to/from QVariant and QString
  • Scripting support
  • Delegates to customize look and feel properties in property widget
  • PEG (property/enum generator) - it's optional tool like Qt moc which generates properties hierarchy from QML like files into C++ code.

Some screenshots of the Demo application: Demo_screenshot_linux Demo_screenshot_win

How to build


  1. Qt 5.2 framework or later
  2. Flex 2.6.4 and Bison 3.1.1 (for Windows can be found here) if you build QtnPEG tool

To build:

mkdir path_to_build
cd path_to_build
qmake path_to_QtnProperty/ -r

Or just open path_to_QtnProperty/ file in Qt Creator and build all. Generated libraries and executables will be placed into the 'path_to_build/bin-[linux|osx|win]' folder.

To run tests and demo:

cd path_to_build/bin-[linux|osx|win]

QtnProperty project consists of five submodules:

  1. QtnPropertyCore static library - property classes (non GUI stuff)
  2. QtnPropertyWidget static library - QtnPropertyWidget, QtnPropertyView and property delegates (GUI stuff)
  3. QtnPEG tool - optional executable to generate C++ code for property sets from simple QML like files (*.pef files)
  4. QtnPropertyTests - tests for QtnPropertyCore library
  5. QtnPropertyDemo - demo application

How to use

Step 1.

To have QtnProperty in your project your should include QtnProperty.pri file into your pro file. It will add QtnPropertyCore and QtnPropertyWidget static libraries to your project.


Step 2.

Then you can manually create property sets in your C++ code, create QtnPropertyWidget or QtnPropertyView widgets and assign property set to the widget:

class Ui_MainWindow
    QtnPropertyWidget *centralWidget;

MainWindow::MainWindow(QWidget *parent) :
    ui(new Ui::MainWindow)

    m_propertySet = new QtnPropertySet(this)

    auto floatValue = qtnCreateProperty<QtnPropertyFloat>(m_propertySet);
    floatValue->setDescription(tr("Float value"));

    auto textColor = qtnCreateProperty<QtnPropertyQColor>(m_propertySet);
    textColor->setDescription(tr("Foreground text color"));
    textColor->setValue(QColor(0, 0, 0));


This example will show you something like this:


Step 3.

If you want to use *.pef files to generate properties C++ code you need to build QtnPEG executable.

Step 4.

To use *.pef files in your project you should do the following in your pro file:

  • Define PEG_TOOL variable as full path to the QtnPEG executable
  • include PEG.pri file
  • list all *.pef files in PEG_SOURCES variable
PEG_SOURCES += TextEditor.pef

Step 5.

Write *.pef file with propertyset declaration. See wiki for more info. For example TextEditor.pef:

#include "Core/PropertyCore.h"

property_set TextEditor
    Bool enableWrapping
        description = "Enable/disable text wrapping";
        value = true;
    Bool replaceTabsWithSpaces
        description = "Automatically replace tabs with spaces";
        value = false;
        slot propertyDidChange
            tabSize.switchState(QtnPropertyStateImmutable, !replaceTabsWithSpaces);
    UInt tabSize
        description = "Number of spaces to be placed.";
        state = QtnPropertyStateImmutable;
        value = 4;

Step 6.

Include generated TextEditor.peg.h and TextEditor.peg.cpp files into your project.

Step 7.

Now you can use QtnPropertySetTextEditor class (defined in generated files) in your C++ code like this:

    QtnPropertySetTextEditor params;
    params.enableWrapping = false;
    if (params.replaceTabsWithSpaces)

Video of GUI testing using Froglogic (c) Squish test framework is here.

Useful links

The following fork has some advanced features:

  • Multi-properties with QtnMultipleProperty. It is useful when you want to show properties of multiple objects at once. When values of objects's properties differ it shows grayed (Multiple properties). When you set a new property value, it will be changed in every dependent object. Multi-property set can be created with qtnCreateQObjectMultiPropertySet function defined in QObjectPropertySet.h or from custom property sets in a loop with qtnPropertiesToMultiSet function where target argument is a multi-property set, and source argument is a source property set you want to join.
  • QVariant properties with QtnCustomPropertyWidget. You can edit QVariant as property set / add/remove subproperties in QVariantMap or QVariantList, copy/paste variant properties.
  • Integer 64 properties QtnPropertyInt64 QtnPropertyUInt64
  • Floating point variants of QPoint, QSize, QRect properties
  • Overriding QtnPropertyDelegateFactory for QtnPropertySet
  • Improvements to sync objects values and property editors
  • Translations EN_RU
You can’t perform that action at this time.