creating rebar control and introduction a band with toolbar into the rebar

Question

I use this code to create a rebar control, and introduction a band with toolbar into the rebar.
But when window is shown up, I can not see the toolbar. and when I check the height of the rebar, in this line of code: int height = wp.rcNormalPosition.bottom - wp.rcNormalPosition.top; I find rebar's height is only 4 pixels.

#include <windows.h> 
#include <stdlib.h>
#include <CommCtrl.h>
#pragma comment(lib, "comctl32.lib")

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
HINSTANCE instance;

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    instance = hInstance;

    WNDCLASSEX wcex; 

    wcex.cbSize = sizeof(WNDCLASSEX);
    wcex.style           = CS_HREDRAW | CS_VREDRAW; 
    wcex.lpfnWndProc    = WndProc; 
    wcex.cbClsExtra     = 0; 
    wcex.cbWndExtra     = 0;  
    wcex.hInstance      = hInstance;
    wcex.hIcon          = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APPLICATION));  
    wcex.hCursor        = LoadCursor(NULL, IDC_ARROW); 
    wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1); 
    wcex.lpszMenuName   = NULL; 
    wcex.lpszClassName  = L"Example"; 
    wcex.hIconSm        = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_APPLICATION));

    RegisterClassEx(&wcex);

    HWND hWnd = CreateWindow(L"Example", L"", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT,
        500, 500, NULL, NULL, hInstance, NULL);

    // Initialize common controls.
    INITCOMMONCONTROLSEX icex;
    icex.dwSize = sizeof(INITCOMMONCONTROLSEX);
    icex.dwICC   = ICC_COOL_CLASSES | ICC_BAR_CLASSES;
    InitCommonControlsEx(&icex);

    HWND hwndRebar = CreateWindowEx(WS_EX_TOOLWINDOW, REBARCLASSNAME, NULL, WS_CHILD | WS_VISIBLE | WS_BORDER, 
                    0, 0, 100, 50, hWnd, NULL, instance, NULL);

    // create toolbar
    HWND hWndToolbar = CreateWindowEx(0 , TOOLBARCLASSNAME, NULL, WS_CHILD | TBSTYLE_TOOLTIPS,
            0, 0, 0, 0, hwndRebar, (HMENU)0, instance, NULL);

    HIMAGELIST hImageList = ImageList_Create(16, 16, ILC_COLOR16 | ILC_MASK, 3, 0);

    SendMessage(hWndToolbar, TB_SETIMAGELIST, (WPARAM)0, (LPARAM)hImageList);
    SendMessage(hWndToolbar, TB_BUTTONSTRUCTSIZE, (WPARAM)sizeof(TBBUTTON), 0);

    TBBUTTON tbb[4] = 
    {
        {0,0,TBSTATE_ENABLED,TBSTYLE_BUTTON},
        {1,1,TBSTATE_ENABLED,TBSTYLE_BUTTON},
        {2,2,TBSTATE_ENABLED,TBSTYLE_BUTTON},
    };

    SendMessage(hWndToolbar, (UINT) TB_ADDBUTTONS, 3, (LPARAM)&tbb);

    SendMessage(hWndToolbar, TB_AUTOSIZE, 0, 0);
    ShowWindow(hWndToolbar , SW_SHOW);

    // Initialize band info.
    REBARBANDINFO rbBand = { sizeof(REBARBANDINFO) };
    rbBand.fMask  = RBBIM_STYLE | RBBIM_TEXT | RBBIM_CHILD | RBBIM_CHILDSIZE | RBBIM_SIZE | RBBIM_COLORS;

    rbBand.fStyle = RBBS_GRIPPERALWAYS;  

    // Get the height of the toolbar.
    DWORD dwBtnSize = (DWORD)SendMessage(hWndToolbar, TB_GETBUTTONSIZE, 0,0);

    // Set values unique to the band with the toolbar.
    rbBand.clrFore = RGB(233, 233, 233);
    rbBand.clrBack = RGB(200, 200, 200);
    rbBand.lpText = TEXT("");
    rbBand.hwndChild = hWndToolbar;
    rbBand.cyChild = LOWORD(dwBtnSize);
    rbBand.cyMinChild = LOWORD(dwBtnSize);
    rbBand.cxMinChild = 3 * HIWORD(dwBtnSize);
    // The default width is the width of the buttons.
    rbBand.cx = 0;

    // Add the band
    SendMessage(hwndRebar, RB_INSERTBAND, (WPARAM)-1, (LPARAM)&rbBand);

    // show the main window
    ShowWindow(hWnd, nCmdShow);

    // check the rebar size
    WINDOWPLACEMENT wp;
    GetWindowPlacement(hwndRebar, &wp);
    int height = wp.rcNormalPosition.bottom - wp.rcNormalPosition.top;

    MSG msg;

    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);  
        DispatchMessage(&msg); 
    }

    return (int) msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
        case WM_CREATE: 
            return 0;

        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
    }
}

Answer 1

As follows from the comments, the solution was:

REBARBANDINFO rbBand;
rbBand.cbSize = REBARBANDINFO_V3_SIZE;
// initialize the rest here

This seems to affect older versions of Windows (specifically, XP), because the original code compiles and runs fine on Windows 7.

This was mentioned in the comments to a MSDN page: http://msdn.microsoft.com/en-us/library/windows/desktop/bb774393.aspx

Answer 2

As was already stated, the cbSize member of the REBARBANDINFO struct needed to be set.

Note the following about the provided code as well:

1. The images on the toolbar buttons don't show up. Right after creating the image list you have to make the following call to load the images:

   SendMessage(hWndToolbar, TB_LOADIMAGES, (WPARAM)IDB_STD_SMALL_COLOR, (LPARAM)HINST_COMMCTRL);
   

2. The TBBUTTON array is declared with a size of 4 but it only gets populated with 3 items. Technically it should be declared as:

   TBBUTTON tbb[3]