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
开发者_如何学运维 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?
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.
}
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 ...
}
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