Thread: Wm_paint/dialog

I fixed the menu! But new problems keep coming!!!

- When does the Window procedure get the WM_PAINT message?
- Dialog:

in resources.rc file:

Code:

IDD_ABOUT DIALOG DISCARDABLE  0, 0, 239, 66
STYLE DS_MODALFRAME | WS_POPUP | WS_CAPTION | WS_SYSMENU
CAPTION "My About Box"
FONT 8, "MS Sans Serif"
BEGIN
    DEFPUSHBUTTON   "&OK",IDOK,174,18,50,14
    PUSHBUTTON      "&Cancel",IDCANCEL,174,35,50,14
    GROUPBOX        "About this program...",IDC_STATIC,7,7,225,52
    CTEXT           "An example program showing how to use Dialog Boxes\r\n\r\nby theForger",
                    IDC_STATIC,16,18,144,33
END

nothing about the dialog in the resource.h file

in part of main code:

Code:

BOOL CALLBACK AboutDlgProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
    switch(Message)
    {
        case WM_INITDIALOG:

        return TRUE;
        case WM_COMMAND:
            switch(LOWORD(wParam))
            {
                case IDOK:
                    EndDialog(hwnd, IDOK);
                break;
                case IDCANCEL:
                    EndDialog(hwnd, IDCANCEL);
                break;
            }
        break;
        default:
            return FALSE;
    }
    return TRUE;
} // is the dialog procedure


case WM_COMMAND: // WM_COMMAND message in windows procedure
        switch(LOWORD(wParam))
        {
            case ID_FILE_EXIT:
                PostMessage(hwnd, WM_CLOSE, 0, 0);
            break;
            case ID_HELP_ABOUT:
            {
            int ret = DialogBox(GetModuleHandle(NULL), 
                MAKEINTRESOURCE(IDD_ABOUT), hwnd, AboutDlgProc);
            if(ret == IDOK){
                MessageBox(hwnd, "Dialog exited with IDOK.", "Notice",
                    MB_OK | MB_ICONINFORMATION);
            }
            else if(ret == IDCANCEL){
                MessageBox(hwnd, "Dialog exited with IDCANCEL.", "Notice",
                    MB_OK | MB_ICONINFORMATION);
            }
            else if(ret == -1){
                MessageBox(hwnd, "Dialog failed!", "Error",
                    MB_OK | MB_ICONINFORMATION);
            }
            }
            break;
            case ID_STUFF_GO:
                hdc = BeginPaint (hwnd, &ps) ;
                GetClientRect (hwnd, &rect) ;
                DrawText (hdc, TEXT ("You pressed the leftmouse button!"), -1, &rect,
                      DT_SINGLELINE | DT_LEFT | DT_BOTTOM) ;
                EndPaint (hwnd, &ps) ;
            break;
        }
        break;

It says: main1.cpp:50: `IDD_ABOUT' undeclared (first use this function)

How can I fix this problem?

>>- When does the Window procedure get the WM_PAINT message?

When you call for it or when the OS calls for it due to your window being covered / uncovered by another window.

To call for you own paint use

InvalidateRect() //send paint msg
UpdateWindow() //post directly to the apps msg que bypassing the OS que for faster drawing

I put the

Code:

#define IDD_ABOUT 100001

in my resource.h file,
but it says (Messagebox) Dialog failed, because

Code:

int ret = DialogBox(GetModuleHandle(NULL), MAKEINTRESOURCE(IDD_ABOUT), hwnd, AboutDlgProc);
                if(ret == IDOK){
                    MessageBox(hwnd, "Dialog exited with IDOK.", "Notice",
                    MB_OK | MB_ICONINFORMATION);
                }
                else if(ret == IDCANCEL){
                    MessageBox(hwnd, "Dialog exited with IDCANCEL.", "Notice",
                    MB_OK | MB_ICONINFORMATION);
                }
                else if(ret == -1){
                    MessageBox(hwnd, "Dialog failed!", "Error",
                    MB_OK | MB_ICONINFORMATION);
                }

What can I do to fix it?

change the return TRUEs to return FALSEs.

Look up DefWindowProc()

Place a break point in the About box's InitDlg handler and default case. I think the dlg is failing after it creates.

I would.......

Change the catch all 'return TRUE' to a 'return FALSE' to show you did not process that msg.

Return the result from a call to DefWndProc() in your 'default' case in the about box's callback (to get windows to process all msgs you don't have code for).