How to get the height and width of a tooltip dynamically in c++?

To get the height and width of a tooltip dynamically in C++, you can use the WinAPI functions GetTextMetrics and DrawText. Here's an example of how you can do it:

cppCopy code
#include <windows.h>



LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)

{

    switch (msg)

    {

        case WM_CREATE:

        {

            // Create a tooltip control

            HWND hwndTT = CreateWindowEx(WS_EX_TOPMOST, TOOLTIPS_CLASS, NULL,

                                         WS_POPUP | TTS_ALWAYSTIP | TTS_NOPREFIX,

                                         CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,

                                         hwnd, NULL, GetModuleHandle(NULL), NULL);



            // Set up tooltip text

            TOOLINFO ti;

            ti.cbSize = sizeof(TOOLINFO);

            ti.uFlags = TTF_IDISHWND | TTF_SUBCLASS;

            ti.hwnd = hwnd;

            ti.uId = (UINT_PTR)hwnd;

            ti.lpszText = LPSTR_TEXTCALLBACK;

            SendMessage(hwndTT, TTM_ADDTOOL, 0, (LPARAM)&ti);



            break;

        }



        case WM_NOTIFY:

        {

            if (((LPNMHDR)lParam)->code == TTN_GETDISPINFO)

            {

                LPNMTTDISPINFO pDispInfo = (LPNMTTDISPINFO)lParam;

                if (pDispInfo->hdr.idFrom == (UINT_PTR)hwnd)

                {

                    // Calculate the size of the tooltip text

                    RECT rect = { 0, 0, 0, 0 };

                    HDC hdc = GetDC(hwnd);

                    HFONT hFont = (HFONT)SendMessage(hwnd, WM_GETFONT, 0, 0);

                    HFONT hOldFont = (HFONT)SelectObject(hdc, hFont);



                    DrawText(hdc, "Tooltip Text", -1, &rect, DT_CALCRECT);



                    SelectObject(hdc, hOldFont);

                    ReleaseDC(hwnd, hdc);



                    // Set the tooltip size

                    pDispInfo->szText.cx = rect.right - rect.left;

                    pDispInfo->szText.cy = rect.bottom - rect.top;

                }



                break;

            }

        }



        case WM_DESTROY:

        {

            PostQuitMessage(0);

            break;

        }



        default:

            return DefWindowProc(hwnd, msg, wParam, lParam);

    }

    return 0;

}



int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)

{

    WNDCLASS wc = { 0 };

    wc.lpfnWndProc = WndProc;

    wc.hInstance = hInstance;

    wc.lpszClassName = "TooltipExample";

    RegisterClass(&wc);



    HWND hwnd = CreateWindow(wc.lpszClassName, "Tooltip Example",

                             WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT,

                             400, 300, NULL, NULL, hInstance, NULL);



    ShowWindow(hwnd, nCmdShow);



    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0) > 0)

    {

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return (int)msg.wParam;

}

In this example, when you hover over the window with your mouse, a tooltip with dynamic height and width will appear based on the size of the text "Tooltip Text." The tooltip size is calculated using DrawText with DT_CALCRECT flag. The WM_NOTIFY message is used to respond to the tooltip request for display information. Make sure to adjust the code to fit your actual use case and UI framework.