Best Libraries for Creating GUI in C++ on Major Operating Systems (Linux, Windows, macOS)

C++ is widely used in developing advanced applications due to its high performance and flexibility, especially when dealing with graphical user interfaces (GUI). Developing GUIs from scratch is not a simple task, requiring powerful tools and libraries. Most developers rely on established libraries to create effective and cross-platform GUIs for their applications on systems such as Windows, Linux, and macOS.

Here’s an overview of the most popular libraries used for GUI design in C++ applications across different platforms.

1. Qt

Overview:

Qt is one of the most popular and powerful libraries for designing GUIs. It supports all major platforms: Windows, Linux, and macOS. Qt is also used for developing mobile applications and web apps, making it a versatile and scalable library.

Advantages:

• Cross-platform: Qt works seamlessly on all major platforms without the need to modify code.

• Rich components: Offers a wide range of pre-built widgets for windows, buttons, and menus, speeding up the development process.

• Wide widget support: Comprehensive support for various UI elements.

• Qt Quick: Allows GUI creation using QML (a descriptive language based on JavaScript).

Example:

#include <QApplication>
#include <QPushButton>

int main(int argc, char **argv) {
    QApplication app(argc, argv);
    QPushButton button("Click Me");
    button.show();
    return app.exec();
}

Drawbacks:

• The size of the library can be relatively large for small projects.

• Learning QML can be challenging at first.

2. wxWidgets

Overview:

wxWidgets is an open-source library for developing cross-platform GUI applications. It serves as a lightweight alternative to Qt and works efficiently on all major platforms while preserving the native look and feel of each operating system.

Advantages:

• Excellent performance across platforms.

• Integration with other libraries: such as OpenGL and DirectX.

• Native components: Uses the platform's native UI elements, providing a familiar experience to users.

Example:

#include <wx/wx.h>

class MyApp : public wxApp {
public:
    virtual bool OnInit();
};

class MyFrame : public wxFrame {
public:
    MyFrame();
};

wxIMPLEMENT_APP(MyApp);

bool MyApp::OnInit() {
    MyFrame *frame = new MyFrame();
    frame->Show(true);
    return true;
}

MyFrame::MyFrame()
    : wxFrame(NULL, wxID_ANY, "Hello wxWidgets!") {
}

Drawbacks:

• Fewer modern features compared to Qt.

• Smaller community support.

3. FLTK (Fast Light Toolkit)

Overview:

FLTK is an extremely lightweight and open-source library used to create GUIs in C++. It’s especially suited for applications that demand speed and performance due to its simplicity and lightweight nature.

Advantages:

• Lightweight and fast.

• Easy to learn and integrate into smaller projects.

• Multi-platform support: Works on Windows, Linux, and macOS.

• OpenGL support: Great for developing 3D graphical applications.

Example:

#include <FL/Fl.H>
#include <FL/Fl_Window.H>
#include <FL/Fl_Button.H>

void ButtonCallback(Fl_Widget* widget, void* data) {
    Fl_Button* button = (Fl_Button*)widget;
    button->label("Clicked!");
}

int main(int argc, char **argv) {
    Fl_Window *window = new Fl_Window(340,180);
    Fl_Button *button = new Fl_Button(20,40,300,100,"Click Me");
    button->callback(ButtonCallback);
    window->end();
    window->show(argc, argv);
    return Fl::run();
}

Drawbacks:

• Limited features compared to Qt or wxWidgets.

• Basic GUI: May not be suitable for complex applications.

4. ImGui (Immediate Mode GUI)

Overview:

ImGui is an open-source library that follows the Immediate Mode approach to GUI creation, making it highly suitable for internal tools and fast-interaction interfaces. It’s commonly used with game engines or graphical applications.

Advantages:

• Highly interactive, offering a smooth user experience.

• Strong integration with OpenGL and DirectX.

• Lightweight and easy to integrate with C++ projects.

Example:

ImGui::Begin("Hello, world!");
ImGui::Text("This is some text!");
ImGui::End();

Drawbacks:

• Limited for traditional GUI design.

• Not ideal for complex, full-featured desktop applications.

5. GTKmm

Overview:

GTKmm is the C++ version of the popular GTK library, widely used for creating GUIs in Linux environments. While it’s primarily known for its Linux support, it can also work on Windows and macOS.

Advantages:

• Rich and advanced GUI capabilities.

• Strong support community, particularly in the Linux ecosystem.

• Suitable for large applications.

Example:

#include <gtkmm.h>

int main(int argc, char *argv[]) {
    auto app = Gtk::Application::create(argc, argv, "org.gtkmm.example");
    Gtk::Window window;
    window.set_default_size(200, 200);
    return app->run(window);
}

Drawbacks:

• Limited compatibility with other operating systems like Windows.

• More complex to learn compared to other libraries.

Conclusion

When selecting a GUI library for developing C++ applications, several factors such as performance, platform compatibility, ease of use, and feature set need to be considered. Libraries like Qt and wxWidgets offer extensive cross-platform support, while FLTK and ImGui are ideal for lightweight or interactive applications. GTKmm is a robust choice for Linux developers who need powerful GUI tools.

Each library has its strengths and weaknesses, and the choice depends on the specific requirements of your project.