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Created December 11, 2018 16:13
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Minimal Windows GUI Program for Win32 API without WinMain - https://caiorss.github.io/C-Cpp-Notes/WindowsAPI-cpp.html#orgc3f65d8
// File: gui-without-winmain.cpp
// Brief: Minimal Windows GUI Program for Win32 API without WinMain.
// Author: Caio Rodrigues
//--------------------------------------------------------------------------------------
#include <iostream>
#include <string>
#include <windows.h>
LRESULT windowProcedure( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
int main(int argc, char** argv){
//---- Get WinMain Parameters ----//
HINSTANCE hInstance = GetModuleHandle(NULL);
STARTUPINFO si;
GetStartupInfo(&si);
int nCmdShow = si.wShowWindow;
// -------------------------//
OutputDebugString("Starting WinMain Application");
std::puts("Starting WinMain Application");
//Window class name must be unique
const char wincClassName [] = "NameOfWindow";
// Win32 Window class structure
WNDCLASSEX wc;
// Win32 message structure
MSG Msg;
wc.lpszClassName = wincClassName;
wc.lpfnWndProc = windowProcedure;
wc.cbSize = sizeof(WNDCLASSEX);
wc.style = 0;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wc.hCursor = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); // (HBRUSH) CreateSolidBrush(RGB(10, 20, 30)); //
wc.lpszMenuName = NULL;
wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
if(!RegisterClassEx(&wc)) {
MessageBox(NULL,
"Window Registration Failed!",
"Error!",
MB_ICONEXCLAMATION | MB_OK);
//Error status code
return -1;
}
std::cout << "Class Registered" << std::endl;
int width = 500, height = 400;
int pos_left = 400, pos_top = 100;
HWND hwnd = CreateWindowA(
wc.lpszClassName,
"Title of Window",
WS_OVERLAPPEDWINDOW,
pos_left,
pos_top,
width,
height,
nullptr,
nullptr,
hInstance,
nullptr
);
constexpr size_t buttonID = 1001;
OutputDebugString(" [INFO] Window created OK");
if(hwnd == NULL){
MessageBox(NULL,
"Error: Failure to create Window",
"Error Report",
MB_ICONEXCLAMATION | MB_OK);
return -1;
}
ShowWindow(hwnd, nCmdShow);
UpdateWindow(hwnd);
//---- Message Loop ----------//
while(GetMessage(&Msg, NULL, 0, 0) > 0 ){
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}
// Success status code
return 0;
}
// ------------ End of Main ------------------------- //
// Window Procedure - Process window messages or events
LRESULT windowProcedure (
HWND hwnd // Window Handle (Window object)
,UINT msg // Window Message
,WPARAM wParam // Additional message information
,LPARAM lParam // Additional message information
){
// Process messages
switch(msg)
{
case WM_CREATE:
break;
case WM_CLOSE:
DestroyWindow(hwnd);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
case WM_MOVE:
break;
case WM_PAINT:
{
// GDI - Graphics Devices Interface Here
//--------------------------------------------
PAINTSTRUCT ps;
HDC hdc;
// std::cerr << " [INFO] Windown painting" << std::endl;
hdc = BeginPaint(hwnd, &ps);
std::string text = "Hello world Window!";
TextOutA(hdc, 125, 200, text.c_str(), text.size());
Ellipse(hdc, 100, 100, 160, 160);
Rectangle(hdc, 100, 100, 160, 160);
EndPaint(hwnd, &ps);
}
break;
default:
return DefWindowProc(hwnd, msg, wParam, lParam);
}
return 0;
}
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