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我想知道如何用 C++ 制作一个透明的程序，我的意思是你能看到的只是窗口的内容（文本/内容）。我也不想使用像 Qt 这样的库，而只使用默认库（如果需要，还可以使用 SDL/OpenGL）。

我不是在控制台之后，我想要一个可以显示图像和文本的窗口。

系统：Windows 7

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2 回答 2

1

它应该是这样的：

SetLayeredWindowAttributes(GetActiveWindow(), NULL, Alpha, LWA_ALPHA);

在这种情况下Alpha是变量 [0; 255] 这决定了透明度的程度。您还需要检查返回值是否为TRUE.

于 2013-07-28T11:41:01.483 回答
0

我在 github 上有一个项目，它创建了一个带有一些自定义的半透明窗口

按钮-> https://github.com/xx4g/twlekezexe

有一个文件 transparentwindowbuilder.cpp 它包含以下功能。

使用 updatelayeredwindow 进行渲染时，我的运气会更好。

通常，当我只想要一个不可见的窗口时，我会使用 setlayeredwindow。

例子 ：

WndProc：重要的是要注意我们必须自己发送 WM_NCLBUTTONDOWN 消息：

LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)                  /* handle the messages */
    {
    case WM_MOVE:
        UpdatePosProc();
        return DefWindowProc(hwnd, message, wParam, lParam);
        break;
    case WM_DESTROY:/* the window was destroyed */
        PostQuitMessage(0);       /* send a WM_QUIT to the message queue */
        break;
    case WM_LBUTTONDOWN:/* the left mouse button was clicked */
        mouseHit = true;
        ::PostMessage(hwnd,WM_NCLBUTTONDOWN,HTCAPTION,lParam);  /* send a HTCAPTION to the message queue */
        return DefWindowProc(hwnd, message, wParam, lParam);
        break;
    default:                      /* for messages that we don't deal with */
        return DefWindowProc(hwnd, message, wParam, lParam);
    }
    return 0;
}

//In main.cpp somewhere
     hWndParent = MakeTransparentWindowProc(hThisInstance, SW_HIDE, L"back1.png", L"PNGDialog1", L"winexe", width, height, WindowProcedure, false,HWND_DESKTOP);
//transparentwindowbuilder.cpp  
    HWND MakeTransparentWindowProc (HINSTANCE hThisInstance,
   

int nCmdShow,
    const wchar_t* ImagePng1, /* This is the PNG image path */
    const wchar_t* windowClassName1,/* This is the class name */
    const wchar_t* windowName1, /* This is the application name */
    int width, /* This is the window width */
    int height,/* This is the window height */
    WNDPROC windocProcedure,
bool toolwindow,HWND Parent)
{
    /* Start GDIPlus */
    ULONG_PTR gdiplusStartupToken;  /* GDIPlus Startup Token */
    Gdiplus::GdiplusStartupInput gdiInput;
    Gdiplus::GdiplusStartup(&gdiplusStartupToken, &gdiInput, NULL);


    /* Make a transparent Window*/

    /* Local Variables*/

    HWND hwnd;               /* This is the handle for our window */
     /* Make Transparent Window */
    auto result = makeTransParentWindow(hThisInstance,  /* the hInstance, Should use WinMains HInstance */
        hwnd,  /* This is the handle for our window */
        nCmdShow,  /* The show Window Flag */
        ImagePng1,  /* The path to the Image File */
        windocProcedure, /* The pointer to the window procedure */
        windowClassName1, /* The name of the NEw class to create */
        width,/* The length */
        height,/* The width */
        windowName1, toolwindow, Parent);

    /* Shut down GDIPlus*/
    Gdiplus::GdiplusShutdown(gdiplusStartupToken);

    return result ? hwnd : nullptr;
}
bool makeTransParentWindow(HINSTANCE& hThisInstance, HWND& hWnd, int& nCmdShow, const wchar_t*& imagePath, WNDPROC lpfnWndProc, const wchar_t*& szClassName, int Width, int Height, const wchar_t*& szWindowName,bool toolwindow,HWND Parent)
{
    WNDCLASSEX wincl;        /* Data structure for the windowclass */

    if (!RegisterWindowClass(wincl, hThisInstance, szClassName, lpfnWndProc)) return false;

    /* The class is registered, let's create the program*/
    if (!CreateWindowPane(hWnd, szClassName, Width, Height, hThisInstance, szWindowName, toolwindow, Parent)) return false;

    /* Make the window visible on the screen */
    ShowWindow(hWnd, nCmdShow);

    RenderWindow(hWnd, imagePath);

    return true;
}

void RenderWindow(HWND& hWnd, const wchar_t*& imagePath)
{
    RECT wndRect;

    ::GetWindowRect(hWnd, &wndRect);

    SIZE wndSize = { wndRect.right - wndRect.left,wndRect.bottom - wndRect.top };

    DrawSizedWindow(hWnd, wndSize, imagePath);
}

void DrawSizedWindow(HWND& hWnd, SIZE& wndSize, const wchar_t*& imagePath)
{
    HDC hdc = ::GetDC(hWnd);

    HDC memDC = ::CreateCompatibleDC(hdc);

    HBITMAP memBitmap = ::CreateCompatibleBitmap(hdc, wndSize.cx, wndSize.cy);

    SelectAndDrawObject(memDC, memBitmap, imagePath, wndSize);

    HDC screenDC = GetDC(NULL);

    BlendLayeredWindow(hWnd, screenDC, wndSize, memDC);

    CleanUpObjects(memDC, memBitmap, hWnd, screenDC);
}

void SelectAndDrawObject(HDC& memDC, const HBITMAP& memBitmap, const wchar_t*& imagePath, SIZE& wndSize)
{
    ::SelectObject(memDC, memBitmap);

    ::DrawGdiImage(imagePath, memDC, wndSize);
}

void BlendLayeredWindow(HWND& hWnd, const HDC& screenDC, SIZE& wndSize, const HDC& memDC)
{
    POINT ptSrc = { 0,0 };

    BLENDFUNCTION blendFunction;

    ::SetBlendFunctionSetiings(blendFunction);

    ::UpdateLayeredWindow(hWnd, screenDC, &ptSrc, &wndSize, memDC, &ptSrc, 0, &blendFunction, 2);
}

void CleanUpObjects(const HDC& memDC, const HBITMAP& memBitmap, HWND& hWnd, const HDC& screenDC)
{
    ::DeleteDC(memDC);

    ::DeleteObject(memBitmap);

    ::ReleaseDC(hWnd, screenDC);
}

void DrawGdiImage(const wchar_t*& imagePath, const HDC& memDC, SIZE& wndSize)
{
    Gdiplus::Image image(imagePath);
    Gdiplus::Graphics graphics(memDC);
    graphics.DrawImage(&image, 0, 0, wndSize.cx, wndSize.cy);
}

bool CreateWindowPane(HWND& hWnd, const wchar_t*& szClassName, int Width, int Height, HINSTANCE& hThisInstance, const wchar_t*& windowName,bool toolwindow,HWND Owner)
{
    if (toolwindow)
    {
        hWnd = CreateWindowEx(
            WS_EX_LAYERED | WS_EX_NOACTIVATE,                   /* Extended possibilites for variation */
            szClassName,         /* Classname */
            windowName,       /* Title Text */
            WS_POPUPWINDOW | WS_CHILD, /* default window */
            CW_USEDEFAULT,       /* Windows decides the position */
            CW_USEDEFAULT,       /* where the window ends up on the screen */
            Width,                 /* The programs width */
            Height,                 /* and height in pixels */
            Owner,        /* The window is a child-window to desktop */
            NULL,                /* No menu */
            hThisInstance,       /* Program Instance handler */
            NULL                 /* No Window Creation data */
        );

    }
    else
    {
        hWnd = CreateWindowEx(
            WS_EX_LAYERED,                   /* Extended possibilites for variation */
            szClassName,         /* Classname */
            windowName,       /* Title Text */
            WS_POPUPWINDOW, /* default window */
            CW_USEDEFAULT,       /* Windows decides the position */
            CW_USEDEFAULT,       /* where the window ends up on the screen */
            Width,                 /* The programs width */
            Height,                 /* 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 */
        );
    }
    return hWnd != nullptr;
}

bool RegisterWindowClass(WNDCLASSEX& wincl, HINSTANCE& hThisInstance, const wchar_t*& szClassName, const WNDPROC& lpfnWndProc)
{
    /* The Window structure */
    wincl.hInstance = hThisInstance;
    wincl.lpszClassName = szClassName;
    wincl.lpfnWndProc = lpfnWndProc;      /* 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(hThisInstance, MAKEINTRESOURCE(IDI_WINEXE));
    wincl.hIconSm = LoadIcon(hThisInstance, MAKEINTRESOURCE(IDI_WINEXE));
    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 Windows's default colour as the background of the window */
    wincl.hbrBackground = (HBRUSH)COLOR_BACKGROUND;

    /* Register the window class, and if it fails quit the program */
    if (!RegisterClassEx(&wincl))
    {
        return false;
    }

    return true;
}

void SetBlendFunctionSetiings(BLENDFUNCTION& blendFunction)
{
    blendFunction.AlphaFormat = AC_SRC_ALPHA;
    blendFunction.BlendFlags = 0;
    blendFunction.BlendOp = AC_SRC_OVER;
    blendFunction.SourceConstantAlpha = 220;
}
于 2021-09-04T16:33:45.980 回答