PS - First Test #1

// Ex4.cpp : Defines the entry point for the application.
//

#include "framework.h"
#include "Ex4.h"
#include <CommCtrl.h>
#include <stdio.h>

#define MAX_LOADSTRING 100

// 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);
INT_PTR CALLBACK    Calculator(HWND, UINT, WPARAM, LPARAM);

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_EX4, szWindowClass, MAX_LOADSTRING);
    MyRegisterClass(hInstance);

    // Perform application initialization:
    if (!InitInstance(hInstance, nCmdShow))
    {
        return FALSE;
    }

    HACCEL hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_EX4));

    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)
{
    WNDCLASSEXW 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_EX4));
    wcex.hCursor = LoadCursor(nullptr, IDC_ARROW);
    wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wcex.lpszMenuName = MAKEINTRESOURCEW(IDC_EX4);
    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)
{
    hInst = hInstance; // Store instance handle in our global variable

    HWND hWnd = CreateWindowW(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, 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
//
//
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;
        case ID_MENU_MESSAGEBOX:
            MessageBox(hWnd, "Message", "Message Box", MB_OK | MB_ICONINFORMATION);
            break;
        case ID_MENU_ENABLEMENU:
        {
            HMENU hMenu = GetMenu(hWnd);
            UINT res = GetMenuState(hMenu, ID_MENU_DISABLED, MF_BYCOMMAND);
            if (res & MF_DISABLED)
            {
                EnableMenuItem(hMenu, ID_MENU_DISABLED, MF_BYCOMMAND | MF_ENABLED);
            }
            else
            {
                EnableMenuItem(hMenu, ID_MENU_DISABLED, MF_BYCOMMAND | MF_DISABLED);
            }
            break;
        }
        case ID_MENU_DELETE:
        {
            HMENU hMenu = GetMenu(hWnd);
            DeleteMenu(hMenu, ID_MENU_DELETED, MF_BYCOMMAND);
            break;
        }
        case ID_MENU_INSERT:
        {
            HMENU hMenu = GetMenu(hWnd);
            if (GetMenuState(hMenu, ID_MENU_MESSAGEBOX + 1, MF_BYCOMMAND) == -1)
            {
                MENUITEMINFO mii;
                ZeroMemory(&mii, sizeof(mii));
                mii.cbSize = sizeof(mii);
                mii.fMask = MIIM_ID | MIIM_TYPE | MIIM_STATE;
                mii.wID = ID_MENU_MESSAGEBOX + 1;
                mii.fType = MFT_STRING;
                mii.dwTypeData = const_cast<char*>("Inserted");
                mii.fState = MFS_ENABLED;
                InsertMenuItem(hMenu, ID_MENU_ENABLEMENU, FALSE, &mii);
            }
            break;
        }
        case ID_MENU_MESSAGEBOX + 1:
            DialogBox(hInst, MAKEINTRESOURCE(IDD_DIALOG1), hWnd, Calculator);
            break;
        default:
            return DefWindowProc(hWnd, message, wParam, lParam);
        }
    }
    break;
    case WM_PAINT:
    {
        PAINTSTRUCT ps;
        HDC hdc = BeginPaint(hWnd, &ps);
        // TODO: Add any drawing code that uses hdc here...
        EndPaint(hWnd, &ps);
    }
    break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}

// Message handler for about box.
INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    UNREFERENCED_PARAMETER(lParam);
    switch (message)
    {
    case WM_INITDIALOG:
        return (INT_PTR)TRUE;

    case WM_COMMAND:
        if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
        {
            EndDialog(hDlg, LOWORD(wParam));
            return (INT_PTR)TRUE;
        }
        break;
    }
    return (INT_PTR)FALSE;
}

INT_PTR CALLBACK Calculator(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    char result[100];
    double a = 0, b = 0, c = 0, math = 0;
    BOOL* LPt = NULL;
    BOOL SIG = TRUE;
    UNREFERENCED_PARAMETER(lParam);
    switch (message)
    {
    case WM_INITDIALOG:
        CheckDlgButton(hDlg, IDC_RADIO1, BST_CHECKED);
        return (INT_PTR)TRUE;

    case WM_COMMAND:
        if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
        {
            EndDialog(hDlg, LOWORD(wParam));
            return (INT_PTR)TRUE;
        }
        else if (LOWORD(wParam) == IDC_BUTTON1)
        {
            if (IsDlgButtonChecked(hDlg, IDC_RADIO1))
            {
                a = GetDlgItemInt(hDlg, IDC_EDIT1, LPt, SIG);
                b = GetDlgItemInt(hDlg, IDC_EDIT2, LPt, SIG);
                c = GetDlgItemInt(hDlg, IDC_EDIT3, LPt, SIG);
                if (c == 0)
                {
                    MessageBox(hDlg, "ERROR: Cannot divise by 0", "Invalid Input", MB_OK | MB_ICONWARNING);
                    break;
                }
                else
                {
                    math = (a + b) / c;
                    sprintf_s(result, "%6.3f", math);
                    SetDlgItemText(hDlg, IDC_EDIT4, result);
                }
            }
            else if (IsDlgButtonChecked(hDlg, IDC_RADIO2))
            {
                a = GetDlgItemInt(hDlg, IDC_EDIT1, LPt, SIG);
                b = GetDlgItemInt(hDlg, IDC_EDIT2, LPt, SIG);
                c = GetDlgItemInt(hDlg, IDC_EDIT3, LPt, SIG);
                math = (a - b) * c;
                sprintf_s(result, "%6.3f", math);
                SetDlgItemText(hDlg, IDC_EDIT4, result);
            }
        }
        break;
    }
    return (INT_PTR)FALSE;
}