background.c

ReactOS是一些高手根据Windows XP的内核编写出的类XP。内核实现机理和API函数调用几乎相同。甚至可以兼容XP的程序。喜欢研究系统内核的人可以看一看。

    TCHAR filename[MAX_PATH];
    TCHAR fileTitle[256];
    TCHAR filter[MAX_PATH];
    BackgroundItem *backgroundItem = NULL;
    SHFILEINFO sfi;
    LV_ITEM listItem;
    HWND hwndBackgroundList;

    hwndBackgroundList = GetDlgItem(hwndDlg, IDC_BACKGROUND_LIST);

    ZeroMemory(&ofn, sizeof(OPENFILENAME));

    ofn.lStructSize = sizeof(OPENFILENAME);
    ofn.hwndOwner = hwndDlg;
    ofn.lpstrFile = filename;

    LoadString(hApplet, IDS_BACKGROUND_COMDLG_FILTER, filter, sizeof(filter) / sizeof(TCHAR));

    /* Set lpstrFile[0] to '\0' so that GetOpenFileName does not
     * use the contents of szFile to initialize itself */
    ofn.lpstrFile[0] = TEXT('\0');
    ofn.nMaxFile = MAX_PATH;
    ofn.lpstrFilter = filter;
    ofn.nFilterIndex = 0;
    ofn.lpstrFileTitle = fileTitle;
    ofn.nMaxFileTitle = 256;
    ofn.lpstrInitialDir = NULL;
    ofn.Flags = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;

    if (GetOpenFileName(&ofn) == TRUE)
    {
        /* Check if there is already a entry that holds this filename */
        if (CheckListViewFilenameExists(hwndBackgroundList, ofn.lpstrFileTitle) == TRUE)
            return;

        if (pGlobalData->listViewItemCount > (MAX_BACKGROUNDS - 1))
            return;

        SHGetFileInfo(filename,
                      0,
                      &sfi,
                      sizeof(sfi),
                      SHGFI_SYSICONINDEX | SHGFI_SMALLICON | SHGFI_DISPLAYNAME);

        backgroundItem = &pGlobalData->backgroundItems[pGlobalData->listViewItemCount];

        backgroundItem->bWallpaper = TRUE;

        _tcscpy(backgroundItem->szDisplayName, sfi.szDisplayName);
        _tcscpy(backgroundItem->szFilename, filename);

        ZeroMemory(&listItem, sizeof(LV_ITEM));
        listItem.mask       = LVIF_TEXT | LVIF_PARAM | LVIF_STATE | LVIF_IMAGE;
        listItem.state      = 0;
        listItem.pszText    = backgroundItem->szDisplayName;
        listItem.iImage     = sfi.iIcon;
        listItem.iItem      = pGlobalData->listViewItemCount;
        listItem.lParam     = pGlobalData->listViewItemCount;

        (void)ListView_InsertItem(hwndBackgroundList, &listItem);

        pGlobalData->listViewItemCount++;
    }
}


static VOID
ListViewItemChanged(HWND hwndDlg, PGLOBAL_DATA pGlobalData, int itemIndex)
{
    BackgroundItem *backgroundItem = NULL;

    pGlobalData->backgroundSelection = itemIndex;
    backgroundItem = &pGlobalData->backgroundItems[pGlobalData->backgroundSelection];

    if (pGlobalData->pWallpaperBitmap != NULL)
    {
        DibFreeImage(pGlobalData->pWallpaperBitmap);
        pGlobalData->pWallpaperBitmap = NULL;
    }

    if (backgroundItem->bWallpaper == TRUE)
    {
        pGlobalData->pWallpaperBitmap = DibLoadImage(backgroundItem->szFilename);

        if (pGlobalData->pWallpaperBitmap == NULL)
            return;
    }

    InvalidateRect(GetDlgItem(hwndDlg, IDC_BACKGROUND_PREVIEW),
                   NULL, TRUE);

    EnableWindow(GetDlgItem(hwndDlg, IDC_COLOR_BUTTON),
                 (backgroundItem->bWallpaper == FALSE ? TRUE : FALSE));
    EnableWindow(GetDlgItem(hwndDlg, IDC_PLACEMENT_COMBO),
                 backgroundItem->bWallpaper);

    PropSheet_Changed(GetParent(hwndDlg), hwndDlg);
}


static VOID
DrawBackgroundPreview(LPDRAWITEMSTRUCT draw, PGLOBAL_DATA pGlobalData)
{
    float scaleX;
    float scaleY;
    int scaledWidth;
    int scaledHeight;
    int posX;
    int posY;
    HBRUSH hBrush;
    int x;
    int y;

    if (pGlobalData->backgroundItems[pGlobalData->backgroundSelection].bWallpaper == FALSE)
    {
        /* update desktop background color image */
        hBrush = CreateSolidBrush(pGlobalData->backgroundDesktopColor);
        FillRect(draw->hDC, &draw->rcItem, hBrush);
        DeleteObject(hBrush);
        return;
    }

    if (pGlobalData->pWallpaperBitmap == NULL)
        return;

    scaleX = ((float)GetSystemMetrics(SM_CXSCREEN) - 1) / (float)draw->rcItem.right;
    scaleY = ((float)GetSystemMetrics(SM_CYSCREEN) - 1) / (float)draw->rcItem.bottom;

    scaledWidth = pGlobalData->pWallpaperBitmap->width / scaleX;
    scaledHeight = pGlobalData->pWallpaperBitmap->height / scaleY;

    posX = (draw->rcItem.right / 2) - (scaledWidth / 2);
    posY = (draw->rcItem.bottom / 2) - (scaledHeight / 2);

    FillRect(draw->hDC, &draw->rcItem, GetSysColorBrush(COLOR_BACKGROUND));

    SetStretchBltMode(draw->hDC, COLORONCOLOR);

    switch (pGlobalData->placementSelection)
    {
        case PLACEMENT_CENTER:
            StretchDIBits(draw->hDC,
                          posX,
                          posY,
                          scaledWidth,
                          scaledHeight,
                          0,
                          0,
                          pGlobalData->pWallpaperBitmap->width,
                          pGlobalData->pWallpaperBitmap->height,
                          pGlobalData->pWallpaperBitmap->bits,
                          pGlobalData->pWallpaperBitmap->info,
                          DIB_RGB_COLORS,
                          SRCCOPY);
            break;

        case PLACEMENT_STRETCH:
            StretchDIBits(draw->hDC,
                          0,
                          0,
                          draw->rcItem.right,
                          draw->rcItem.bottom,
                          0,
                          0,
                          pGlobalData->pWallpaperBitmap->width,
                          pGlobalData->pWallpaperBitmap->height,
                          pGlobalData->pWallpaperBitmap->bits,
                          pGlobalData->pWallpaperBitmap->info,
                          DIB_RGB_COLORS,
                          SRCCOPY);
            break;

        case PLACEMENT_TILE:
            for (y = 0; y < draw->rcItem.bottom; y += scaledHeight)
            {
                for (x = 0; x < draw->rcItem.right; x += scaledWidth)
                {
                    StretchDIBits(draw->hDC,
                                  x,
                                  y,
                                  scaledWidth,
                                  scaledHeight,
                                  0,
                                  0,
                                  pGlobalData->pWallpaperBitmap->width,
                                  pGlobalData->pWallpaperBitmap->height,
                                  pGlobalData->pWallpaperBitmap->bits,
                                  pGlobalData->pWallpaperBitmap->info,
                                  DIB_RGB_COLORS,
                                  SRCCOPY);
                }
            }
            break;
    }
}


static VOID
SetWallpaper(PGLOBAL_DATA pGlobalData)
{
    HKEY regKey;

    RegOpenKeyEx(HKEY_CURRENT_USER, TEXT("Control Panel\\Desktop"), 0, KEY_ALL_ACCESS, &regKey);

    if (pGlobalData->placementSelection == PLACEMENT_TILE)
    {
        RegSetValueEx(regKey, TEXT("TileWallpaper"), 0, REG_SZ, (BYTE *)TEXT("1"), sizeof(TCHAR) * 2);
        RegSetValueEx(regKey, TEXT("WallpaperStyle"), 0, REG_SZ, (BYTE *)TEXT("0"), sizeof(TCHAR) * 2);
    }

    if (pGlobalData->placementSelection == PLACEMENT_CENTER)
    {
        RegSetValueEx(regKey, TEXT("TileWallpaper"), 0, REG_SZ, (BYTE *)TEXT("0"), sizeof(TCHAR) * 2);
        RegSetValueEx(regKey, TEXT("WallpaperStyle"), 0, REG_SZ, (BYTE *)TEXT("0"), sizeof(TCHAR) * 2);
    }

    if (pGlobalData->placementSelection == PLACEMENT_STRETCH)
    {
        RegSetValueEx(regKey, TEXT("TileWallpaper"), 0, REG_SZ, (BYTE *)TEXT("0"), sizeof(TCHAR) * 2);
        RegSetValueEx(regKey, TEXT("WallpaperStyle"), 0, REG_SZ, (BYTE *)TEXT("2"), sizeof(TCHAR) * 2);
    }

    RegCloseKey(regKey);

    if (pGlobalData->backgroundItems[pGlobalData->backgroundSelection].bWallpaper == TRUE)
    {
        SystemParametersInfo(SPI_SETDESKWALLPAPER,
                             0,
                             pGlobalData->backgroundItems[pGlobalData->backgroundSelection].szFilename,
                             SPIF_UPDATEINIFILE);
    }
    else
    {
        SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, (void*) TEXT(""), SPIF_UPDATEINIFILE);
    }
}


/* Change system color */
static VOID
SetDesktopBackColor(HWND hwndDlg, PGLOBAL_DATA pGlobalData)
{
    INT iElement = COLOR_BACKGROUND;
    HKEY hKey;
    LONG result;
    TCHAR clText[16];
    DWORD red, green, blue;

    if( !SetSysColors( 1, &iElement, &pGlobalData->backgroundDesktopColor ) )
        MessageBox(hwndDlg, TEXT("SetSysColor() failed!"), /* these error texts can need internationalization? */
            TEXT("Error!"), MB_ICONSTOP );
    /* Write color to registry key: HKEY_CURRENT_USER\Control Panel\Colors\Background */
    hKey = NULL;
    result = ERROR_SUCCESS;
    result = RegOpenKeyEx( HKEY_CURRENT_USER, TEXT("Control Panel\\Colors"), 0, KEY_WRITE, &hKey );
    if( result != ERROR_SUCCESS )
    {
        /* Key open failed; maybe it does not exist? create it! */
        result = RegCreateKeyEx( HKEY_CURRENT_USER, TEXT("Control Panel\\Colors"), 0, NULL, 0,
            KEY_ALL_ACCESS, NULL, &hKey, NULL );
        /* Now key must be created and opened and hKey must point at newly created key */
        /* On error result will not contain ERROR_SUCCESS. I don't know how to handle */
        /* this case :( */
    }
    red   = GetRValue(pGlobalData->backgroundDesktopColor);
    green = GetGValue(pGlobalData->backgroundDesktopColor);
    blue  = GetBValue(pGlobalData->backgroundDesktopColor);
    _stprintf(clText, TEXT("%d %d %d"), red, green, blue ); /* format string to be set to registry */
    RegSetValueEx(hKey, TEXT("Background"), 0, REG_SZ, (BYTE *)clText, lstrlen( clText )*sizeof(TCHAR) + sizeof(TCHAR) );
    RegCloseKey(hKey);
}


INT_PTR CALLBACK
BackgroundPageProc(HWND hwndDlg,
                   UINT uMsg,
                   WPARAM wParam,
                   LPARAM lParam)
{
    PGLOBAL_DATA pGlobalData;

    pGlobalData = (PGLOBAL_DATA)GetWindowLongPtr(hwndDlg, DWLP_USER);

    switch (uMsg)
    {
        case WM_INITDIALOG:
            pGlobalData = (GLOBAL_DATA*) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(GLOBAL_DATA));
            SetWindowLongPtr(hwndDlg, DWLP_USER, (LONG_PTR)pGlobalData);
            InitBackgroundDialog(hwndDlg, pGlobalData);
            break;

        case WM_COMMAND:
            {
                DWORD controlId = LOWORD(wParam);
                DWORD command   = HIWORD(wParam);

                switch (controlId)
                {
                    case IDC_COLOR_BUTTON:
                        if (command == BN_CLICKED)
                            OnColorButton(hwndDlg, pGlobalData);
                        break;

                    case IDC_BROWSE_BUTTON:
                        if (command == BN_CLICKED)
                            OnBrowseButton(hwndDlg, pGlobalData);
                        break;

                    case IDC_PLACEMENT_COMBO:
                        if (command == CBN_SELCHANGE)
                        {
                            pGlobalData->placementSelection = (int)SendDlgItemMessage(hwndDlg, IDC_PLACEMENT_COMBO, CB_GETCURSEL, 0, 0);

                            InvalidateRect(GetDlgItem(hwndDlg, IDC_BACKGROUND_PREVIEW), NULL, TRUE);

                            PropSheet_Changed(GetParent(hwndDlg), hwndDlg);
                        }
                        break;
                }
            } break;

        case WM_PAINT:
            {
                PAINTSTRUCT ps;
                HDC hdc, hdcMem;

                hdc = BeginPaint(hwndDlg, &ps);

                hdcMem = CreateCompatibleDC(hdc);
                SelectObject(hdcMem, pGlobalData->hBitmap);
/*
                TransparentBlt(hdc, 98, 0,
                               pGlobalData->cxSource, pGlobalData->cySource, hdcMem, 0, 0,
                               pGlobalData->cxSource, pGlobalData->cySource, 0xFF80FF);
*/
                DeleteDC(hdcMem);
                EndPaint(hwndDlg, &ps);
            }
            break;

        case WM_DRAWITEM:
            {
                LPDRAWITEMSTRUCT drawItem;
                drawItem = (LPDRAWITEMSTRUCT)lParam;

                if (drawItem->CtlID == IDC_BACKGROUND_PREVIEW)
                {
                    DrawBackgroundPreview(drawItem, pGlobalData);
                }

            }
            break;

        case WM_NOTIFY:
            {
                LPNMHDR lpnm = (LPNMHDR)lParam;

                switch(lpnm->code)
                {
                    case PSN_APPLY:
                        SetWallpaper(pGlobalData);
                        SetDesktopBackColor(hwndDlg, pGlobalData);
                        return TRUE;

                    case LVN_ITEMCHANGED:
                        {
                            LPNMLISTVIEW nm = (LPNMLISTVIEW)lParam;

                            if ((nm->uNewState & LVIS_SELECTED) == 0)
                                return FALSE;

                            ListViewItemChanged(hwndDlg, pGlobalData, nm->iItem);

                        } break;
                }
            }
            break;

        case WM_DESTROY:
            if (pGlobalData->pWallpaperBitmap != NULL)
                DibFreeImage(pGlobalData->pWallpaperBitmap);

            DeleteObject(pGlobalData->hBitmap);
            HeapFree(GetProcessHeap(), 0, pGlobalData);
            break;
    }

    return FALSE;
}