How to make window non transparent?

Question

Dear All

I want to make parent window as non transparent with RGB value as (99,99,99)? Previously my window was transparent but now i have requirement to make window as non transparent.

Mentioned below are the function related to my parent window:

ATOM MyRegisterClass(HINSTANCE hInstance)
{
    LogEntry(L"Entered in myRegisterClass Function");

    WNDCLASS CLASS_NAME_ONE_SEG_APP;
    CLASS_NAME_ONE_SEG_APP.cbClsExtra = 0;
    CLASS_NAME_ONE_SEG_APP.cbWndExtra = 0;
    CLASS_NAME_ONE_SEG_APP.hbrBackground = 0;
    CLASS_NAME_ONE_SEG_APP.hCursor = 0;
    CLASS_NAME_ONE_SEG_APP.hIcon = 0;
    CLASS_NAME_ONE_SEG_APP.hInstance = hInstance;
    CLASS_NAME_ONE_SEG_APP.lpfnWndProc =  (WNDPROC) WndProc;
    CLASS_NAME_ONE_SEG_APP.lpszClassName = className;
    CLASS_NAME_ONE_SEG_APP.lpszMenuName = 0;
    CLASS_NAME_ONE_SEG_APP.style = 0;

    LogEntry(L"Exiting from myRegisterClass Function");

    return RegisterClass(&CLASS_NAME_ONE_SEG_APP); 
}

Mentioned below is an InitInstance function in which i am creating the parent window.

handles.parent is my parent window.

bool WINAPI InitInstance(HINSTANCE hInstance, int nCmdShow)
{
    LogEntry(L"Entered in InitInstance Function");
    handles.parent = CreateWindowEx(0,
                                    className,
                                    windowName, 
                                    WS_VISIBLE | WS_POPUP,
                                    0, 0, 
                                    coordinates.width, coordinates.height,
                                    NULL, 
                                    NULL, 
                                    hInstance, 
                                    NULL);

    if(handles.parent == NULL)
    {
        LogValue(L"Cannot Create Parent Window"
            L"\nInitInstance Function terminated abnormally");
        return false;
    }
    else
    {
        UpdateWindow(handles.parent);
        ShowWindow(handles.parent, nCmdShow);
        LogEntry(L"Exiting from InitInstance Function");
        return true;
    }
}

The below mentioned is a function for WM_PAINT:

case WM_PAINT:
        LogEntry(L"Entred in WM_PAINT");
        PaintWindow(); 
        SetFocus(handles.parent);
        LogEntry(L"Exited from WM_PAINT");
        break;

This PaintWindow does the following.....

void PaintWindow()
{
    LogEntry(L"Entered in PaintWindow Function");
    HWND *handle = &handles.volUp;

    //Paint Buttons on the window
    for(register char i =  MIN_BUTTON; i <= MAX_BUTTON; i++)
    {
        PaintButton( (INITIAL_BUTTON + i) , *handle, btns, i);
        handle++;
    }

    //Paint the AXIS_VOL_ON_OFF Button According to its Status
    if(volumeStatus.status == VOLUME_ON)
        PaintButton(IDB_BTN_VOL_OFF, handles.volOnOff, btns, AXIS_VOL_ON_OFF);
    else if(volumeStatus.status = VOLUME_MUTE)
        PaintButton(IDB_BTN_VOL_ON, handles.volOnOff, btns, AXIS_VOL_ON_OFF);

    //Paint Images on the window
    if(handles.screenMode == SCREEN_MODE_OPERATION)
        InsertImages();

    LogEntry(L"Exited from PaintWindow Function");
}

Thanks in advance......

Answer 1

You need to give your class a non-null background brush

  CLASS_NAME_ONE_SEG_APP.hbrBackground = CreateSolidBrush(RGB((99,99,99));

And in your WindowProc, you need to make sure that you pass the WM_ERASEBKGND message to DefWindowProc. (that part is probably already happening)

Later

Ok, your WM_PAINT code is doing some things wrong. It's important that you call BeginPaint and EndPaint when you handle the WM_PAINT message, and you have to use the HDC that you get from BeginPaint when you draw.

case WM_PAINT:
    {
    LogEntry(L"Entred in WM_PAINT");

    PAINTSTRUCT ps;
    HDC hdc = BeginPaint(&ps);
    PaintWindow(hdc); 
    EndPaint(hwnd, &ps);

    LogEntry(L"Exited from WM_PAINT");
    }  
    break;

Your window is transparent because you never call BeginPaint in your WM_PAINT handler, so you never end up drawing anything to the screen.

See Drawing in the Client Area for a more complete example.