calling a function from a button

[MPrestonf12]

I've tried to call a function from a button on a window. But nothing happens. I am calling it as I would in a console app but that's not working. How do you call it from a button? thanks

[SteveCRM]

It should work...post your code.

[MPrestonf12]

#include <windows.h>

HWND ghWnd_button1;
HWND hwnd; /* This is the handle for our window */

/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure(HWND, UINT, WPARAM, LPARAM);
/* Make the class name into a global variable */
char szClassName[ ] = "WindowsApp";
int WINAPI WinMain(HINSTANCE hThisInstance, HINSTANCE hPrevInstance, LPSTR lpszArgument, int nFunsterStil)

{

    MSG messages;            /* Here messages to the application are saved */
    WNDCLASSEX wincl;        /* Data structure for the windowclass */

    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;      /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                 /* Catch double-clicks */
    wincl.cbSize = sizeof(WNDCLASSEX);

    /* Use default icon and mouse-pointer */
    wincl.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wincl.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor(NULL, IDC_ARROW);
    wincl.lpszMenuName = NULL; /* No menu */
    wincl.cbClsExtra = 0;                      /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                      /* structure or the window instance */
    /* Use light-gray as the background of the window */
    wincl.hbrBackground = (HBRUSH) GetStockObject(LTGRAY_BRUSH);

    /* Register the window class, if fail quit the program */
    if(!RegisterClassEx(&wincl)) return 0;

    /* The class is registered, let's create the program*/
    hwnd = CreateWindowEx(
           0,                   /* Extended possibilites for variation */
           szClassName,         /* Classname */
           "Windows App",         /* Title Text */
           WS_OVERLAPPEDWINDOW, /* default window */
           CW_USEDEFAULT,       /* Windows decides the position */
           CW_USEDEFAULT,       /* where the window ends up on the screen */
           544,                 /* The programs width */
           375,                 /* and height in pixels */
           HWND_DESKTOP,        /* The window is a child-window to desktop */
           NULL,                /* No menu */
           hThisInstance,       /* Program Instance handler */
           NULL                 /* No Window Creation data */
           );

ghWnd_button1 = CreateWindow("Button", "Button 1", \
								  WS_CHILD | WS_VISIBLE, \
								  50, 50, 200, 40,hwnd, NULL, hThisInstance, NULL);

    /* Make ULL,hThisInstance,Nthe window visible on the screen */
    ShowWindow(hwnd, nFunsterStil);
    /* Run the message loop. It will run until GetMessage( ) returns 0 */
    while(GetMessage(&messages, NULL, 0, 0))
    {
           /* Translate virtual-key messages into character messages */
           TranslateMessage(&messages);
           /* Send message to WindowProcedure */
           DispatchMessage(&messages);
    }

    /* The program return-value is 0 - The value that PostQuitMessage( ) gave */
    return messages.wParam;
}

/* This function is called by the Windows function DispatchMessage( ) */
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)                  /* handle the messages */
    {      case WM_COMMAND:
			if(LOWORD(wParam) == BN_CLICKED && (HWND)lParam == ghWnd_button1) {
                    int space(5);
                }
           case WM_DESTROY:
           PostQuitMessage(0);        /* send a WM_QUIT to the message queue */
           break;
           default:                   /* for messages that we don't deal with */
           return DefWindowProc(hwnd, message, wParam, lParam);
    }
    return 0;
}

int test(int i)
{
MessageBox(hwnd,i, "My Messagebox", MB_OK);
return 0;
}

[SteveCRM]

First of all...I don't see a prototype. Next, in your button you say int space(5), but you only have the function

int test(int i)

[MPrestonf12]

ok, i think i corrected it but still nothing. Here is the corrected code(not functioning).

#include <windows.h>
#include <stdlib.h>
#include <iostream>

int test();

HWND ghWnd_button1;
HWND hwnd; /* This is the handle for our window */

/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure(HWND, UINT, WPARAM, LPARAM);
/* Make the class name into a global variable */
char szClassName[ ] = "WindowsApp";
int WINAPI WinMain(HINSTANCE hThisInstance, HINSTANCE hPrevInstance, LPSTR lpszArgument, int nFunsterStil)

{
    MSG messages;            /* Here messages to the application are saved */
    WNDCLASSEX wincl;        /* Data structure for the windowclass */

    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = WindowProcedure;      /* This function is called by windows */
    wincl.style = CS_DBLCLKS;                 /* Catch double-clicks */
    wincl.cbSize = sizeof(WNDCLASSEX);

    /* Use default icon and mouse-pointer */
    wincl.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wincl.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    wincl.hCursor = LoadCursor(NULL, IDC_ARROW);
    wincl.lpszMenuName = NULL; /* No menu */
    wincl.cbClsExtra = 0;                      /* No extra bytes after the window class */
    wincl.cbWndExtra = 0;                      /* structure or the window instance */
    /* Use light-gray as the background of the window */
    wincl.hbrBackground = (HBRUSH) GetStockObject(LTGRAY_BRUSH);

    /* Register the window class, if fail quit the program */
    if(!RegisterClassEx(&wincl)) return 0;

    /* The class is registered, let's create the program*/
    hwnd = CreateWindowEx(
           0,                   /* Extended possibilites for variation */
           szClassName,         /* Classname */
           "Windows App",         /* Title Text */
           WS_OVERLAPPEDWINDOW, /* default window */
           CW_USEDEFAULT,       /* Windows decides the position */
           CW_USEDEFAULT,       /* where the window ends up on the screen */
           544,                 /* The programs width */
           375,                 /* and height in pixels */
           HWND_DESKTOP,        /* The window is a child-window to desktop */
           NULL,                /* No menu */
           hThisInstance,       /* Program Instance handler */
           NULL                 /* No Window Creation data */
           );

ghWnd_button1 = CreateWindow("Button", "Button 1", \
								  WS_CHILD | WS_VISIBLE, \
								  50, 50, 200, 40,hwnd, NULL, hThisInstance, NULL);

    /* Make ULL,hThisInstance,Nthe window visible on the screen */
    ShowWindow(hwnd, nFunsterStil);
    /* Run the message loop. It will run until GetMessage( ) returns 0 */
    while(GetMessage(&messages, NULL, 0, 0))
    {
           /* Translate virtual-key messages into character messages */
           TranslateMessage(&messages);
           /* Send message to WindowProcedure */
           DispatchMessage(&messages);
    }

    /* The program return-value is 0 - The value that PostQuitMessage( ) gave */
    return messages.wParam;
}

/* This function is called by the Windows function DispatchMessage( ) */
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
                      /* handle the messages */

    {
    case WM_COMMAND:
			if(LOWORD(wParam) == BN_CLICKED && (HWND)lParam == ghWnd_button1)
                int test();
                 //When it gets here if i use break it does it exits with no messagebox. If i don't it just does not seem to exacute the function.
           case WM_DESTROY:
           PostQuitMessage(0);        /* send a WM_QUIT to the message queue */
           break;
           default:                   /* for messages that we don't deal with */
           return DefWindowProc(hwnd, message, wParam, lParam);
    }
    return 0;
}

int test()
{
MessageBox (NULL, "hello" , "hello", 0);
return 0;
}

I appreciate your help. Im still pretty new at this.

[parksie]

case WM_COMMAND:
	if(LOWORD(wParam) == BN_CLICKED && (HWND)lParam == ghWnd_button1)
		test();
	break;

You don't need to redefine anything else.