How to change the background color of the title bar color C++/SDL2

Question

I have a problem with changing the background color in the title bar window. Is it possible to change with SDL2? Want to change from white color to black, like that

Answer 1

I don't think that's possible with just SDL2, but you can get the native window and use that.

Looking at your screenshot, I assume you are using Windows. You can get the HWND like this (see this answer):

SDL_SysWMinfo wmInfo;
SDL_VERSION(&wmInfo.version);
SDL_GetWindowWMInfo(window, &wmInfo);
HWND hwnd = wmInfo.info.win.window;

Once you have that, you'll want to set both the border color and the caption color (see this answer):

#include <dwmapi.h>

COLORREF titlebar_color = 0x0015171E;
DwmSetWindowAttribute(
    hwnd, DWMWINDOWATTRIBUTE::DWMWA_BORDER_COLOR,
    &titlebar_color, sizeof(titlebar_color)
);

DwmSetWindowAttribute(
    hwnd, DWMWINDOWATTRIBUTE::DWMWA_CAPTION_COLOR,
    &titlebar_color, sizeof(titlebar_color))
);

Of course, all of that only works on Windows (10 or later I think), and, as far as I understand, isn't even guaranteed to work. So you may want to error-check everything.

Another solution that isn't exactly what you ask for but is done entirely within SDL2 is to create a borderless window and draw your own title bar...