buttons are all highlighted - c++

Question

I have two buttons. Each button is highlighted instead of just the first one. How do I make the first button to be only the one highlighted?
BTW This is the code for the two buttons:
openFileButton = CreateWindowA("button", "Open File and start hashing", WS_VISIBLE | WS_CHILD | SS_CENTER, 220, 210, 200, 50, hWnd,
(HMENU)BUTTON_OPEN_FILE, NULL, NULL);
SendMessage(openFileButton, WM_SETFONT, my_font, true);
hashFileButton = CreateWindowA("button", "Get the File hash", WS_VISIBLE | WS_CHILD | SS_CENTER, 220, 270, 200, 50, hWnd,
(HMENU)BUTTON_HASH_FILE, NULL, NULL);
SendMessage(hashFileButton, WM_SETFONT, my_font, true);
Tried using SetFocus but got no luck.

Answer 1

First, stop calling the A versions of WinAPI functions. Those went obsolete back in the '90s. Use the W versions instead, with L prefixes on your string literals and wchar_t as your character type.
Second, you are passing the wrong style flags for buttons. Specifically, you are passing SS_CENTER. This is a style for static controls (hence the SS_ prefix), not for buttons. SS_CENTER is #defined in the Windows header files as the value 0x1, which is equivalent to the button style, BS_DEFPUSHBUTTON. (Note that #define macros are not type-safe, so the compiler doesn't know and can't warn you that you're specifying a static-control style when creating a button control.)
The presence of this erroneous BS_DEFPUSHBUTTON style is why your buttons are both appearing highlighted, as if they are the default button in a dialog box. For standard buttons, you want BS_PUSHBUTTON, which is #defined as the value 0x0, and thus equivalent to not passing any style flags to your CreateWindow function. But for readability and self-documenting code, I would strongly recommend explicitly passing BS_PUSHBUTTON.
So, your corrected code becomes:
openFileButton = CreateWindowW(L"button",
L"Open File and Start Hashing",
WS_VISIBLE | WS_CHILD | BS_PUSHBUTTON,
220, 210, 200, 50,
hWnd,
(HMENU)BUTTON_OPEN_FILE,
NULL,
NULL);
SendMessage(openFileButton, WM_SETFONT, my_font, true);
hashFileButton = CreateWindowW(L"button",
L"Get the File Hash",
WS_VISIBLE | WS_CHILD | BS_PUSHBUTTON,
220, 270, 200, 50,
hWnd,
(HMENU)BUTTON_HASH_FILE,
NULL,
NULL);
SendMessage(hashFileButton, WM_SETFONT, my_font, true);
You might actually want to make one (and only one) of your buttons into the "default" button using the BS_DEFPUSHBUTTON style. The behavior is easily implemented by calling the IsDialogMessage function within your main message loop (behavior which you would get for "free" by creating a dialog box, with the added boon of the Resource Editor to lay out the controls and set styles).