C++ WinAPI input [closed] - c++

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I'm trying to get a Windows/DirectX Input in my little program. I have tried it now for 2 days, but it is not working as expected.
It only recognizes the WM_KEYDOWN message if I asked for the WM_QUIT message before that. I can't find the solution to this weird problem. You can see the code below.
while(m_Running)
{
if(PeekMessage(&msg,NULL,0,0,PM_REMOVE))
{
if(msg.message == WM_QUIT)
{
MessageBox(NULL,"QUIT",NULL,MB_OK);
}
if(msg.message == WM_KEYDOWN)
{
MessageBox(NULL,"PRESS",NULL,MB_OK);
}
TranslateMessage(&msg);
DispatchMessage(&msg);
}
if(Update() == false)
{
m_Running = false;
}
}

Answer 1

You should move your handlers into a win proc:
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_QUIT:
// ....
break;
case WM_KEYDOWN:
// ....
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;
}
And change your loop to:
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
Also, when you create your window class:
myclass.lpfnWndProc = WndProc;

Answer 2

Following on from the link I posted, I've downloaded Visual Studio Express 2013 and compiled run the following, tested it works.
This contains window and class creation, a message loop, and a windows procedure to process messages.
// Trim fat from windows
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
// Windows Procedure Message Handler
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
// Switch message, condition that is met will execute*/
switch (message)
{
case WM_CLOSE:
MessageBox(NULL, "QUIT", NULL, MB_OK);
PostQuitMessage(0);
break;
case WM_KEYDOWN:
MessageBox(NULL, "PRESS", NULL, MB_OK);
break;
default:
return DefWindowProc(hwnd, message, wParam, lParam);
}
return 0;
}
// Main function
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{
WNDCLASSEX windowClass; //window class
HWND hwnd; //window handle
MSG msg; //message
/* Fill out the window class structure*/
windowClass.cbSize = sizeof(WNDCLASSEX);
windowClass.style = CS_HREDRAW | CS_VREDRAW;
windowClass.lpfnWndProc = WndProc;
windowClass.cbClsExtra = 0;
windowClass.cbWndExtra = 0;
windowClass.hInstance = hInstance;
windowClass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
windowClass.hCursor = LoadCursor(NULL, IDC_ARROW);
windowClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
windowClass.lpszMenuName = NULL;
windowClass.lpszClassName = "MyClass";
windowClass.hIconSm = LoadIcon(NULL, IDI_WINLOGO);
/* Register window class*/
if (!RegisterClassEx(&windowClass))
{
return 0;
}
/* Class registerd, so now create window*/
hwnd = CreateWindowEx(NULL, //extended style
"MyClass", //class name
"A Real Win App", //app name
WS_OVERLAPPEDWINDOW | //window style
WS_VISIBLE |
WS_SYSMENU,
100, 100, //x/y coords
400, 400, //width,height
NULL, //handle to parent
NULL, //handle to menu
hInstance, //application instance
NULL); //no extra parameter's
/* Check if window creation failed*/
if (!hwnd)
return 0;
bool done = false; //initialize loop condition variable
/* main message loop*/
while (!done)
{
PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE);
if (msg.message == WM_QUIT) //check for a quit message
{
done = true;
}
else
{
// Translate and dispatch to event queue
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return msg.wParam;
}