messages between window procedures

[xandaz]

    I have this code:

Code Select Expand

         .elseif ax==IDM_MDIOPEN
            invoke  SendMessage,hMdi,uMsg,wParam,lParam
         .elseif ax==IDM_MDISAVEAS
            invoke  SendMessage,hMdi,uMsg,wParam,lParam
         .elseif ax==IDM_MDISAVE
            invoke  SendMessage,hMdi,uMsg,wParam,lParam
         .elseif ax==IDM_MDICLOSE
            invoke  SendMessage,hMdi,uMsg,wParam,lParam
         .endif           

...to send the mdimenu messages to the propper window procedure but the message does't get to the MDIClient Proc. Can anyone give me some insight into this matter? thanks

[HSE]

Hi xandaz!

Just send the message to the other window.

[xandaz]

   The other window is the MDiClient. That's the code presented. ty

[HSE]

   The other window is the MDiClient. That's the code presented. ty

No matter.

A window can send a message to other window, obviously:
1- you know or find the handle of the other window
2 - the other window must understand message   
3 - take care if the other window respond sending a message to another window, you can make a mess 

[xandaz]

    ty HSE. looking into it. thanks

[TimoVJL]

An old C version of MDI windows

Code Select Expand

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include "MDIFrame.h"

const char MainClassName[]  = "MainMDIWnd";
const char ChildClassName[] = "MDIChildWnd";

const int StartChildrenNo = 994;

HWND hWndMainFrame  = NULL;
HWND hWndChildFrame = NULL;

BOOL CreateNewDocument(HINSTANCE hInstance);
LRESULT CALLBACK MainWndProc(HWND hwnd, UINT msg,
WPARAM wParam, LPARAM lParam);
BOOL CreateNewDocument(HINSTANCE hInstance);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR lpCmdLine, int nCmdShow)
{
WNDCLASSEX WndClsEx;
MSG Msg;

WndClsEx.cbSize = sizeof(WNDCLASSEX);
WndClsEx.style = 0;
WndClsEx.lpfnWndProc = MainWndProc;
WndClsEx.cbClsExtra = 0;
WndClsEx.cbWndExtra = 0;
WndClsEx.hInstance = hInstance;
WndClsEx.hIcon = LoadIcon(NULL, IDI_ASTERISK);
WndClsEx.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClsEx.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
WndClsEx.lpszMenuName  = MAKEINTRESOURCE(IDR_MAIN_MENU);
WndClsEx.lpszClassName = MainClassName;
WndClsEx.hIconSm = LoadIcon(NULL, IDI_ASTERISK);

if(!RegisterClassEx(&WndClsEx))
{
MessageBox(NULL,
       "Window Registration Failed!", "Error!",
       MB_OK);
return 0;
}

if( !CreateNewDocument(hInstance) )
return 0;

hWndMainFrame = CreateWindowEx(0L,
  MainClassName,
  "Multiple Document Application",
  WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN,
  CW_USEDEFAULT,
  CW_USEDEFAULT,
  CW_USEDEFAULT,
  CW_USEDEFAULT,
  NULL,
  NULL,
  hInstance,
  NULL);

if(hWndMainFrame == NULL)
{
MessageBox(NULL, "Window Creation Failed!", "Error!",
MB_ICONEXCLAMATION | MB_OK);
return 0;
}

ShowWindow(hWndMainFrame, nCmdShow);
//UpdateWindow(hWndMainFrame);

while(GetMessage(&Msg, NULL, 0, 0) > 0)
{
if (!TranslateMDISysAccel(hWndChildFrame, &Msg))
{
TranslateMessage(&Msg);
DispatchMessage(&Msg);
}
}
return 0;
}

HWND CreateNewMDIChild(HWND hMDIClient)
{
MDICREATESTRUCT mcs;
HWND NewWnd;

mcs.szTitle = "Untitled";
mcs.szClass = ChildClassName;
mcs.hOwner  = GetModuleHandle(NULL);
mcs.x = mcs.cx = CW_USEDEFAULT;
mcs.y = mcs.cy = CW_USEDEFAULT;
mcs.style = MDIS_ALLCHILDSTYLES;

NewWnd = (HWND)SendMessage(hMDIClient, WM_MDICREATE, 0, (LONG)&mcs);

if( !NewWnd )
{
MessageBox(NULL,
   "Error creaing child window",
   "Creation Error",
   MB_OK);
}
return NewWnd;
}

LRESULT CALLBACK MainWndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
switch(Msg)
{
case WM_CREATE:
{
CLIENTCREATESTRUCT ccs;

ccs.hWindowMenu  = GetSubMenu(GetMenu(hWnd), 2);
ccs.idFirstChild = StartChildrenNo;

hWndChildFrame = CreateWindowEx(WS_EX_CLIENTEDGE,
    "MDICLIENT",
   NULL,
   WS_CHILD | WS_CLIPCHILDREN | WS_VSCROLL
            | WS_HSCROLL | WS_VISIBLE,
   CW_USEDEFAULT,
   CW_USEDEFAULT,
   680,
   460,
   hWnd,
   (HMENU)IDM_FILE_NEW,
   GetModuleHandle(NULL),
   (LPVOID)&ccs);

if(hWndChildFrame == NULL)
MessageBox(hWnd, "Could not create MDI client.", "Error", MB_OK | MB_ICONERROR);
}
CreateNewMDIChild(hWndChildFrame);
break;
case WM_SIZE:
{
HWND hWndMDI;
RECT rctClient;

GetClientRect(hWnd, &rctClient);

hWndMDI = GetDlgItem(hWnd, IDM_FILE_NEW);
SetWindowPos(hWndMDI, NULL, 0, 0, rctClient.right, rctClient.bottom, SWP_NOZORDER);
}
break;
case WM_CLOSE:
DestroyWindow(hWnd);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
case WM_COMMAND:
switch(LOWORD(wParam))
{
case IDM_FILE_NEW:
CreateNewMDIChild(hWndChildFrame);
break;
case IDM_FILE_CLOSE:
{
HWND hChild = (HWND)SendMessage(hWndChildFrame, WM_MDIGETACTIVE,0,0);
if(hChild)
{
SendMessage(hChild, WM_CLOSE, 0, 0);
}
}
break;
case IDM_FILE_EXIT:
PostMessage(hWnd, WM_CLOSE, 0, 0);
break;
case IDM_WINDOW_TILE:
SendMessage(hWndChildFrame, WM_MDITILE, 0, 0);
break;

case IDM_WINDOW_CASCADE:
SendMessage(hWndChildFrame, WM_MDICASCADE, 0, 0);
break;

case IDM_WINDOW_ICONS:
SendMessage(hWndChildFrame, WM_MDIICONARRANGE, 0, 0);
break;

case IDM_WINDOW_CLOSE_ALL:
{
HWND hWndCurrent;

do {
hWndCurrent = (HWND)SendMessage(hWndChildFrame, WM_MDIGETACTIVE,0,0);
SendMessage(hWndCurrent, WM_CLOSE, 0, 0);
}while(hWndCurrent);
}
break;

default:
{
if(LOWORD(wParam) >= StartChildrenNo)
{
DefFrameProc(hWnd, hWndChildFrame, WM_COMMAND, wParam, lParam);
}
else
{
HWND hWndCurrent = (HWND)SendMessage(hWndChildFrame, WM_MDIGETACTIVE,0,0);
if( hWndCurrent )
{
SendMessage(hWndCurrent, WM_COMMAND, wParam, lParam);
}
}
}
}
break;
default:
return DefFrameProc(hWnd, hWndChildFrame, Msg, wParam, lParam);
}
return 0;
}

LRESULT CALLBACK ChildWndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch(msg)
{
case WM_CREATE:
break;

case WM_MDIACTIVATE:
{
HMENU hMenu, hFileMenu;
UINT EnableFlag;

hMenu = GetMenu(hWndMainFrame);
if(hwnd == (HWND)lParam)
{
EnableFlag = MF_ENABLED;
}
else
{
EnableFlag = MF_GRAYED;
}

EnableMenuItem(hMenu, 1, MF_BYPOSITION | EnableFlag);
EnableMenuItem(hMenu, 2, MF_BYPOSITION | EnableFlag);

hFileMenu = GetSubMenu(hMenu, 0);

EnableMenuItem(hFileMenu, IDM_FILE_CLOSE, MF_BYCOMMAND | EnableFlag);
EnableMenuItem(hFileMenu, IDM_WINDOW_CLOSE_ALL, MF_BYCOMMAND | EnableFlag);

DrawMenuBar(hWndMainFrame);
}
break;

default:
return DefMDIChildProc(hwnd, msg, wParam, lParam);
}
return 0;
}

BOOL CreateNewDocument(HINSTANCE hInstance)
{
WNDCLASSEX WndClsEx;

WndClsEx.cbSize = sizeof(WNDCLASSEX);
WndClsEx.style = CS_HREDRAW | CS_VREDRAW;
WndClsEx.lpfnWndProc = ChildWndProc;
WndClsEx.cbClsExtra = 0;
WndClsEx.cbWndExtra = 0;
WndClsEx.hInstance = hInstance;
WndClsEx.hIcon = LoadIcon(NULL, IDI_WARNING);
WndClsEx.hCursor = LoadCursor(NULL, IDC_ARROW);
WndClsEx.hbrBackground = (HBRUSH)(COLOR_BTNFACE + 1);
WndClsEx.lpszMenuName  = NULL;
WndClsEx.lpszClassName = ChildClassName;
WndClsEx.hIconSm = LoadIcon(NULL, IDI_WARNING);

if(!RegisterClassEx(&WndClsEx))
{
MessageBox(NULL,
   "There was a problem when attempting to create a document",
   "Application Error",
   MB_OK);
return FALSE;
}
else
return TRUE;
}


[hutch--]

Its usually the case that an MDI app points all of its control to the MDI window that has the focus. This means all of the menus and toolbar buttons. You normally switch between windows with a menu that is dynamically constructed and you have a dynamically constructed handle "hFocus" or similar that changes with the focus.

Its been about 20 years since I wrote an MDI app as I don't like the interface but you need to get this basic architecture right and the rest becomes easy to extend.

[TouEnMasm]

This demo of mdi ,that i have modify,can be usefull.

[xandaz]

   Yeah, thanks. I already fixed the problem. The messages should be sent to child windows rather than the mdiclient window.
Thanks y'all