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| #include <windows.h>
//The main window handle
HWND MainWindowHandle = 0;
//Necessary to initialise a Windows application
bool InitWindowApp(HINSTANCE instanceHandle, int show);
//Wraps the code to initialize a Windows application
int Run();
//The window procedure, handles events our window receives
LRESULT CALLBACK WndProc(HWND hWnd,
UINT msg,
WPARAM wParam,
LPARAM lParam);
//Windows equivalant to main()
int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
PSTR pCmdLine,
int nShowCmd)
{
//First we create and initialize our Windows application
if(!InitWindowApp(hInstance, nShowCmd))
{
::MessageBox(0, L"Init - Failed", L"Error", MB_OK);
return 0;
}
//Once application has been created and initialized,
//we enter the message loop. We stay in the message
//loop until a WM_QUIT message is received,
//indicating the application should be terminated.
return Run(); //enter message loop
}
bool InitWindowApp(HINSTANCE instanceHandle, int show)
{
//Describe the window's characteristics by filling out a WNDCLASS structure
WNDCLASS wc;
wc.style = CS_HREDRAW | CS_VREDRAW;
wc.lpfnWndProc = WndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = instanceHandle;
wc.hIcon = ::LoadIcon(0, IDI_APPLICATION);
wc.hCursor = ::LoadCursor(0, IDC_ARROW);
wc.hbrBackground = static_cast<HBRUSH>(::GetStockObject(WHITE_BRUSH));
wc.lpszMenuName = 0;
wc.lpszClassName = L"Hello";
//Register the window class description
if(!::RegisterClass(&wc))
{
::MessageBox(0, L"RegisterClass - Failed", 0, 0);
return false;
}
//Create a window with the CreateWindow function
//Note, this function returns a HWND to the created window
//which we save in MainWindowHandle. Through MainWindowHandle
//we can reference this particular window we are creating
MainWindowHandle = ::CreateWindow(
L"Hello",
L"Hello",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
0,
0,
instanceHandle,
0);
if(MainWindowHandle == 0)
{
::MessageBox(0, L"CreateWindow - Failed", 0, 0);
return false;
}
::ShowWindow(MainWindowHandle, show);
::UpdateWindow(MainWindowHandle);
return true;
}
int Run()
{
MSG msg;
::ZeroMemory(&msg, sizeof(MSG));
//The function GetMessage will return 0 (false)
//when a WM_QUIT message is received.
while(::GetMessage(&msg, 0, 0, 0))
{
//Translate the message and then dispatch it
//to the appropriate window procedure.
::TranslateMessage(&msg);
::DispatchMessage(&msg);
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND windowHandle,
UINT msg,
WPARAM wParam,
LPARAM lParam)
{
switch(msg)
{
//In the case the left mouse button was pressed
//then display a messge box
case WM_LBUTTONDOWN:
::MessageBox(0, L"Hello World", L"Hello", MB_OK);
return 0;
//In the case the escape key was pressed
//then destroy the main application window,
//which is identified by MainWindowHandle.
case WM_KEYDOWN:
if(wParam == VK_ESCAPE)
{
::DestroyWindow(windowHandle);
return 0;
}
case WM_DESTROY:
::PostQuitMessage(0);
return 0;
}
return ::DefWindowProc(MainWindowHandle,
msg,
wParam,
lParam);
} |
