Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

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

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?

like image 843
Will Marcouiller Avatar asked Dec 17 '10 18:12

Will Marcouiller


People also ask

What is List Box example?

A list box is a graphical control element that allows the user to select one or more items from a list contained within a static, multiple line text box. The user clicks inside the box on an item to select it, sometimes in combination with the ⇧ Shift or Ctrl in order to make multiple selections.

How many types of listbox controls are there?

The types of forms: Simple forms, each representing a subset of the application's data. Composite forms, composed of several simple forms. Ad hoc grids, in which you aren't confined by the form's design.

What is CreateWindowEx?

The winuser. h header defines CreateWindowEx as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant.

What is the second parameter of Create window?

The second parameter is the window title, of type std::string.


1 Answers

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 | WS_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.
}
like image 115
Will Marcouiller Avatar answered Nov 15 '22 00:11

Will Marcouiller