WinAPI menu doesn't appear after adding edit control - c++

Question

I am learning how to use WinAPI with C++, and am creating an application which at the moment just has a basic edit control for someone to enter their username.
void AddMenus(HWND hWnd)
{
hMenu = CreateMenu();
hSubMenu = CreateMenu();
AppendMenu(hMenu, MF_POPUP, (UINT_PTR)hSubMenu, L"File");
AppendMenu(hSubMenu, MF_STRING, FILE_MENU_EXIT, L"Exit");
SetMenu(hWnd, hMenu);
}
void AddControls(HWND hWnd)
{
hUNameS = CreateWindowW(L"static", L"Username: ", WS_VISIBLE | WS_CHILD | ES_CENTER,
100, 50, 100, 25, hWnd, NULL, NULL, NULL);
hUName = CreateWindowW(L"edit", L" ", WS_VISIBLE | WS_CHILD | WS_BORDER,
202, 50, 100, 25, hWnd, NULL, NULL, NULL);
}
When using the following block of code to create the window, both the controls and the menu don't appear.
case WM_CREATE:
AddControls(hWnd);
AddMenus(hWnd);
break;
If I comment out the AddControls, then the menu appears fine, but if I leave them both as shown, then the menu doesn't appear. Nothing changes if I swap the order of the function calls.
Both the menu and the controls appear if I set the second parameter of the edit control to NULL, but then I get a different problem, where any text I type in the control is invisible until I click it, and then disappears again when I continue to type. The only way I have found to fix this is by having a placeholder which then removes the menu.
TLDR: I can't get both the menu and controls to appear at the same time, and without the second parameter of the edit control being set, then text is invisible to start with.

Answer 1

The code of your first question:
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_COMMAND:
{
int wmId = LOWORD(wParam);
// Parse the menu selections:
switch (wmId)
{
case FILE_MENU_DESTROY:
{
DestroyWindow(hWnd);
break;
}
case FILE_MENU_ABOUT:
{
MessageBox(hWnd, L"about", L"About", MB_OK);
break;
}
break; //this break will not break outside case WM_COMMAND, but only break outside the switch (wmId).
}
}
case WM_CREATE:
AddControls(hWnd);
AddMenus(hWnd);
break;
...
}
need to move the break; above the WM_CREATE to break WM_COMMAND case. Otherwise, when you createwindow and receive WM_COMMAND, WinMenu(AddMenus for this case) will be executed multiple times. I can reproduce with this code.
Modify to:
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_COMMAND:
{
int wmId = LOWORD(wParam);
// Parse the menu selections:
switch (wmId)
{
case FILE_MENU_DESTROY:
{
DestroyWindow(hWnd);
break;
}
case FILE_MENU_ABOUT:
{
MessageBox(hWnd, L"about", L"About", MB_OK);
break;
}
}
}
break;
case WM_CREATE:
AddControls(hWnd);
AddMenus(hWnd);
break;
...
}
This works for me, and the whole project:
#define MAX_LOADSTRING 100
#define FILE_MENU_DESTROY 1
#define FILE_MENU_ABOUT 2
// Global Variables:
HINSTANCE hInst; // current instance
WCHAR szTitle[MAX_LOADSTRING]; // The title bar text
WCHAR szWindowClass[MAX_LOADSTRING]; // the main window class name
// Forward declarations of functions included in this code module:
ATOM MyRegisterClass(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE, int);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
//INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM);
//Custom Application Function Forwrd Declarations
void WinControls(HWND);
void WinMenu(HWND);
HMENU hMenu;
int APIENTRY wWinMain(_In_ HINSTANCE hInstance,
_In_opt_ HINSTANCE hPrevInstance,
_In_ LPWSTR lpCmdLine,
_In_ int nCmdShow)
{
UNREFERENCED_PARAMETER(hPrevInstance);
UNREFERENCED_PARAMETER(lpCmdLine);
// TODO: Place code here.
// Initialize global strings
LoadStringW(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING);
LoadStringW(hInstance, IDC_RANKTOOLADVANCED, szWindowClass, MAX_LOADSTRING);
MyRegisterClass(hInstance); //Generates an instance of a window class
// Perform application initialization:
if (!InitInstance(hInstance, nCmdShow))
{
return FALSE;
}
HACCEL hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_RANKTOOLADVANCED));
MSG msg;
// Main message loop:
while (GetMessage(&msg, nullptr, 0, 0))
{
if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return (int)msg.wParam;
}
//
// FUNCTION: MyRegisterClass()
//
// PURPOSE: Registers the window class.
//
ATOM MyRegisterClass(HINSTANCE hInstance)//Class properties of the window
{
WNDCLASSEXW wcex;
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc; //assigns a window to the instance of the class
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance; //creates an instance
wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_RANKTOOLADVANCED));
wcex.hCursor = LoadCursor(nullptr, IDC_ARROW); //defines a type of cursor (arrow, help, cross, etc.)
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wcex.lpszMenuName = MAKEINTRESOURCEW(IDC_RANKTOOLADVANCED);
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL));
return RegisterClassExW(&wcex);
}
//
// FUNCTION: InitInstance(HINSTANCE, int)
//
// PURPOSE: Saves instance handle and creates main window
//
// COMMENTS:
//
// In this function, we save the instance handle in a global variable and
// create and display the main program window.
//
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{//initializes instance of window class (invocation)
hInst = hInstance; // Store instance handle in our global variable
HWND hWnd = CreateWindowW(szWindowClass, L"test", WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, 0, 900, 600, nullptr, nullptr, hInstance, nullptr);
if (!hWnd)
{
return FALSE;
}
ShowWindow(hWnd, nCmdShow);
UpdateWindow(hWnd);
return TRUE;
}
//
// FUNCTION: WndProc(HWND, UINT, WPARAM, LPARAM)
//
// PURPOSE: Processes messages for the main window.
//
// WM_COMMAND - process the application menu
// WM_PAINT - Paint the main window
// WM_DESTROY - post a quit message and return
//
//
void AddMenus(HWND hWnd)
{
hMenu = CreateMenu();
HMENU hSubMenu = CreateMenu();
AppendMenu(hMenu, MF_POPUP, (UINT_PTR)hSubMenu, L"File");
AppendMenu(hSubMenu, MF_STRING, FILE_MENU_DESTROY, L"Exit");
SetMenu(hWnd, hMenu);
}
void AddControls(HWND hWnd)
{
HWND hUNameS = CreateWindowW(L"static", L"Username: ", WS_VISIBLE | WS_CHILD | ES_CENTER,
100, 50, 100, 25, hWnd, NULL, NULL, NULL);
HWND hUName = CreateWindowW(L"edit", L" ", WS_VISIBLE | WS_CHILD | WS_BORDER,
202, 50, 100, 25, hWnd, NULL, NULL, NULL);
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_COMMAND:
{
int wmId = LOWORD(wParam);
// Parse the menu selections:
switch (wmId)
{/*
case IDM_ABOUT:
DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
break;
case IDM_EXIT:
DestroyWindow(hWnd);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
case FILE_MENU_NEW:
{
MessageBox(hWnd, L"task failed successfully", L"you done goofed", MB_OK | MB_ICONEXCLAMATION);
break;
}*/
case FILE_MENU_DESTROY:
{
DestroyWindow(hWnd);
break;
}
case FILE_MENU_ABOUT:
{
MessageBox(hWnd, L"about", L"About", MB_OK);
break;
}
}
}
break;
case WM_CREATE:
AddControls(hWnd);
AddMenus(hWnd);
break;
case WM_DESTROY:
{
PostQuitMessage(0);
break;
}
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}