如何使用 GUI 在 C++ 中创建框架/窗口？

Question

I want to basiically create a window with C++. It should have a control panel like structure, with the option to toggle a button. The button's image should be from a bitmap, one for ON and other for OFF.

It should have an array of such individual control buttons, like a control panel. I should be able to toggle ON/OFF. But I've to build this tiny application using C++. Kindly guide me on to start and proceed?

Answer 1

You should have a look on these:

• Qt
• GTK+
• wxWidgets

and then choose depending on your need and preferencies.

EDIT:

if you are on Windows, you can use WinAPI. But you loose portability of your code among another OSs.

Answer 2

Why not make it simple? Produce your code in Java, to the point of having a jar file, and then create an executable for each of the three major O/S's from that jar using Launch4J.

Java has frames (JFrames), panels (JPanels) and controls like buttons (JButtons), that you need to build your project, they offer lots of methods to customize each object, and they show doc and prototypes for each one, at least in NetBeans.

Java is also object-oriented, but if you have to stick to C++ for a class then I wish you well. This ease of use, in that it is so much like C++, is what led me to abandon that language for Java two decades ago and today is the first day I've come back to check on the status of C++ GUI's. It hasn't changed and I see no reason to go back.

Answer 3

Unfortunately GUI in C++ is not that simple.

You're going to have to interact with the OS at some point to achieve this, which means you will need some sort of library to use.

To better answer your question (as has been mentioned in the comments) you will need to identify what kind of OS you are targeting? The usual three are:

• Windows
• Mac
• Linux

With what information you've given though: I recommend using the SFML Library or something similar. There are tutorials available and it works quite well cross-platform. To open a window you just instantiate a class like so:

sf::Window window(sf::VideoMode(800, 600), "My window");

Drawing buttons is a little harder. Many libraries provide their own solutions, so I'll avoid giving a specific example, and the below is only psuedo-code. In general though, you want to capture when the user clicks, then get their Mouse/Pointer Position (x, y) on screen, and check it against the boundaries of each corner of the button's rectangle:

if (ButtonPressed())
{
    int currentX = GetMousePositionX();
    int currentY = GetMousePositionY();

    if (currentX > button.Left() &&
        currentX < button.Right() &&
        currentY > button.Top() &&
        currentY < button.Bottom())
    {
        // The button is pressed
    }
}

The code example above does assume that the MousePosition starts at 0, 0 at the top left of the window, which different libraries do differently. So you'll want to check how the library you're using implements it.

You might also want to consider foregoing the GUI entirely (if this is really just a small project, GUI in C++ can be surprisingly difficult).