Qt is an inter-platform computer program development system, which includes a library of control elements, used both to create programs with graphical interface and applications without a graphical interface, such as servers.
The most common uses of Qt are KDE, Opera web browser, Google Earth, Skype, Qtopia. The Norwegian company Trolltech produces qt.
Starting with version 4, Qt is available for all platforms, including Windows under a dual license, LPG, and a proprietary license.
This makes it possible to develop LPG-licensed Qt applications and other systems, the most notable being the availability of KDE 4 for Windows and Mac OS X.
Qt, with its complementary elements of C ++ language deficiencies and its truly multi-platform framework that practically covers all the basic needs, solves both issues, ensuring a gratifying and clean development. Thus the Qt became the de facto standard of the C++ development framework.
Qt is a UI framework and comprehensive application. It has a consistent and clean API. Qt provides a robust communication mechanism between objects.
It is genuinely multi-platform, but at the same time manages to provide all the necessary low-level functionalities and native UI behaviors of the operating systems it supports.
It also provides a set of development tools for rapid application development (RAD), which can replace or integrate into significant IDEs such as Visual Studio or Eclipse.
It is deeply documented, has a large and influential community behind it and is widely adopted.
Qt brings a collection of libraries to meet all the basic needs in application development.
Of course, as is the case with any other framework, Qt was not meant to satisfy any whim of any developer in the world, but practically also covers a general framework.
Qt has a set of libraries called QtCore that covers, as the name suggests, a set of basic functionality and without providing an exhaustive enumeration, this basic package includes the following:
1. An application environment with an event loop and an event system;
2. A GUI system that is one of the most powerful aspects of Qt.
3.Container with templates, such as list, queue, vector, and dictionary.
They offer a perfect alternative to STL containers, bringing both Java-style and STL-style iteration mechanisms, as well as conversion to the corresponding STL types.
4. Resource management classes;
5. A model-view system for decoupling visual representation data based on a set of abstract classes;
6. A thread-frame that exists and has been appreciated for a long time;
7. Production of regular strings and expressions;
8. The operating system features such as file processing, printing, network functionalities, and system settings.
In addition, there are several other packages, most of them mature and feature-rich in the respective areas.
These include XML processing, multimedia capabilities, SQL database support, unit testing, OpenGL, WebKit integration, libraries and internationalization tools, SVG manipulation, D-Bus communication, ActiveX controls, and more.
Undoubtedly, there are disadvantages to Qt. For Windows platform exclusive development, a .NET-based solution may be handier for some.
Qt has come to be a pretty big frame, so it might be a bit harder to use it and there are also sometimes problems with database drivers and threading but the benefits far outweigh the disadvantages.