Win32: How to create a ListBox control using the CreateWindowExW() function?

问题

I've been through multiple sites, documents and tutorials and they all say the same, that is, any control is nothing more than a window in Win32's API, hence one is able to use the CreateWindowExW() function to create a ListBox control/window over the main application window.

Though I get the concepts of all controls being windows with different dwStyle, I have a hard time finding out how to instantiate, to say so, the ListBox control.

I encountered a tutorial where a dialog is written to have a LISTBOX specified in its declaration as follows:

// resource.h
#define IDD_MAIN                        101
#define IDC_TEXT                        1000
#define IDC_NUMBER                      1001
#define IDC_LIST                        1002
#define IDC_ADD                         1003
#define IDC_CLEAR                       1004
#define IDC_REMOVE                      1005
#define IDC_SHOWCOUNT                   1006

// .rc resource file
IDD_MAIN DIALOG DISCARDABLE  0, 0, 207, 156
    STYLE DS_MODALFRAME | DS_CENTER | WS_POPUP | WS_CAPTION | WS_SYSMENU
    CAPTION "Controls One"
    FONT 8, "MS Sans Serif"
BEGIN
    LTEXT           "Add",IDC_STATIC,7,10,14,8
    EDITTEXT        IDC_TEXT,25,7,120,14,ES_AUTOHSCROLL
    EDITTEXT        IDC_NUMBER,150,7,21,14,ES_NUMBER
    LTEXT           "times.",IDC_STATIC,177,10,23,8
    LISTBOX         IDC_LIST,7,25,138,106,LBS_NOINTEGRALHEIGHT | 
                    LBS_EXTENDEDSEL | WS_VSCROLL | WS_TABSTOP
    PUSHBUTTON      "&Add",IDC_ADD,150,30,50,14
    PUSHBUTTON      "&Remove",IDC_REMOVE,150,47,50,14
    PUSHBUTTON      "&Clear",IDC_CLEAR,150,63,50,14
    LTEXT           "This item was added",IDC_STATIC,7,141,66,8
    CTEXT           "-",IDC_SHOWCOUNT,77,141,32,8
    LTEXT           "times",IDC_STATIC,114,141,17,8
END

And using it in his C program like so:

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
    return DialogBox(hInstance, MAKEINTRESOURCE(IDD_MAIN), NULL, DlgProc);
}

Now, this I am able to do and fully understand the concepts. Aside, I would like to be able to create and design my main application window to add a ListBox control to. This tutorial example doesn't use the CreateWindowExW() function to create the control, instead, it creates a dialog that will actually be the main application window.

1 - Any clue on how to add a ListBox control to the main window in code?

I thought about creating it while handling the WM_CREATE message.

2 - Is this a good idea?

3 - What is the best practice/approach in this scenario?

回答1:

In order to dynamically create a control in Win32's you need the following code:

HWND hBtn
    , hLabel
    , hListbox
    , hTextBox;

void InitializeComponent(HWND hWnd) {
    HINSTANCE hInstance = GetModuleHandle(NULL);

    // Adding a Button.
    hBtn = CreateWindowExW(WS_EX_APPWINDOW
        , L"BUTTON", NULL
        , WS_CHILD | WS_VISIBLE
        , 327, 7, 70, 21
        , hWnd, NULL, hInstance, NULL);        

    SetWindowTextW(hBtn, L"&Button");

    // Adding a Label.
    hLabel = CreateWindowExW(WS_EX_CLIENTEDGE
        , L"STATIC", NULL
        , WS_CHILD | WS_VISIBLE
        , 7, 7, 50, 21
        , hWnd, NULL, hInstance, NULL);

    SetWindowTextW(hLabel, L"Label:");

    // Adding a ListBox.
    hListBox = CreateWindowExW(WS_EX_CLIENTEDGE
        , L"LISTBOX", NULL
        , WS_CHILD | WS_VISIBLE | ES_VSCROLL | ES_AUTOVSCROLL
        , 7, 35, 300, 200
        , hWnd, NULL, hInstance, NULL);

    // Adding a TextBox.
    hTextBox = CreateWindowExW(WS_EX_CLIENTEDGE
        , L"EDIT", NULL
        , WS_CHILD | WS_VISIBLE | ES_AUTOVSCROLL
        , 62, 7, 245, 21
        , hWnd, NULL, hInstance, NULL);

    SetWindowTextW(hTextBox, L"Input text here...");
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam) {
    switch (Msg) {
        case WM_CREATE:
            InitializeComponent(hWnd);
            break;            
        default:
            return DefWindowProcW(hWnd, Msg, wParam, lParam);
    }
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd) {
    // Declaring, defining, registering and creating window here...
    // Note that each Window/Control has to have its own Message handling function.
}

回答2:

HWND hListBox; // Handle for list box control

hListBox = CreateWindowEx(
  WS_EX_CLIENTEDGE, // extended window styles
  "LISTBOX", // list box window class name
  NULL,
  WS_CHILD | WS_VISIBLE, // window styles
  7,   // horizontal position
  35,  // vertical position
  300, // width
  200, // height
  hWnd,
  NULL,
  hInstance,
  NULL
);

if (!hListBox){
  // failed to create list box window - take actions ...
}

来源：https://stackoverflow.com/questions/4473431/win32-how-to-create-a-listbox-control-using-the-createwindowexw-function

标签

listbox

winapi

createwindow