C++ 在非客户区绘图时如何保持控制盒响应

我正在使用下面的代码绘制一个图像，该图像在我的窗口的非客户端区域扩展。代码可以工作，但控制框（最小化、最大化和关闭按钮）保持无响应，单击时不会发生任何事情。如何在非客户区绘图，使我的控制箱保持响应

下面是我在Windows 7上运行的应用程序的屏幕截图：

我的代码是：

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    WTA_OPTIONS ops;
    ops.dwFlags = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
    ops.dwMask = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
    SetWindowThemeNonClientAttributes(winId(), ops.dwMask, ops.dwFlags);

    MARGINS margins = {-1};
    DwmExtendFrameIntoClientArea(winId(), &margins);
}

bool MainWindow::winEvent(MSG *pMessage, long *result)
{
    HWND hWnd = pMessage->hwnd;
    UINT message = pMessage->message;
    WPARAM wParam = pMessage->wParam;
    LPARAM lParam = pMessage->lParam;

    DwmDefWindowProc(hWnd, message, wParam, lParam, NULL);

    if(message == WM_PAINT)
    {
        HDC hDC = GetWindowDC(hWnd);
        PaintCustomCaption(hWnd, hDC);
        DeleteDC(hDC);
        return true;
    }

    if(message == WM_NCCALCSIZE) return true;

    if(message == WM_NCHITTEST) return true;

    return QWidget::winEvent(pMessage, result);
}

QPixmap pixmap;

void MainWindow::PaintCustomCaption(HWND hWnd, HDC hdc)
{
    RECT rcClient;
    GetClientRect(hWnd, &rcClient);

    HDC hdcPaint = CreateCompatibleDC(hdc);

    HDC hdcRes = CreateCompatibleDC(hdc);

    if (pixmap.isNull()) pixmap = QPixmap("png.png");

    HBITMAP hBmpRes = pixmap.toWinHBITMAP(QPixmap::PremultipliedAlpha);

    SIZE szBmpRes;
    BITMAP rBitmap;
    GetObject(hBmpRes, sizeof (BITMAP), &rBitmap);
    szBmpRes.cx = rBitmap.bmWidth;
    szBmpRes.cy = rBitmap.bmHeight;

    HBITMAP hOldBmpRes = (HBITMAP)SelectObject(hdcRes, hBmpRes);

    if (hdcPaint)
    {
        int cx = rcClient.right - rcClient.left;
        int cy = rcClient.bottom - rcClient.top;

        BITMAPINFO dib = {0};
        dib.bmiHeader.biSize            = sizeof(BITMAPINFOHEADER);
        dib.bmiHeader.biWidth           = cx;
        dib.bmiHeader.biHeight          = -cy;
        dib.bmiHeader.biPlanes          = 1;
        dib.bmiHeader.biBitCount        = 32;
        dib.bmiHeader.biCompression     = BI_RGB;

        HBITMAP hbm = CreateDIBSection(hdc, &dib, DIB_RGB_COLORS, NULL, NULL, 0);

        if (hbm)
        {
            HBITMAP hbmOld = (HBITMAP)SelectObject(hdcPaint, hbm);
            BitBlt(hdcPaint, 0, 0, cx, cy, hdcRes, 0, 0, SRCCOPY);
            BitBlt(hdc, 0, 0, cx, cy, hdcPaint, 0, 0, SRCCOPY);
            SelectObject(hdcPaint, hbmOld);
            DeleteObject(hbm);
        }
        DeleteDC(hdcPaint);
    }
    SelectObject(hdcRes, (HBITMAP)hOldBmpRes);
    DeleteObject(hBmpRes);
    DeleteDC(hdcRes);
}

---

在几次尝试之后，我编写了这段代码来绘制一个图像，该图像在Qt窗口的非客户端区域扩展，在Windows7下测试

结果截图：

及有关守则：

在.pro文件中：

LIBS += -lGdi32
LIBS += -lUser32
LIBS += -lDwmApi
LIBS += -lUxTheme

在头文件中：

#include <dwmapi.h>

#define LEFTEXTENDWIDTH 8
#define RIGHTEXTENDWIDTH 8
#define BOTTOMEXTENDWIDTH 20
#define TOPEXTENDWIDTH 161

private slots:
    void PaintCustomCaption(HWND hWnd, HDC hdc);
    LRESULT HitTestNCA(HWND hWnd, LPARAM lParam);

protected:
    bool winEvent(MSG *pMessage, long *result);

private:
    QPixmap pixmap;

#包括
#定义LEFTEXTENDWIDTH 8
#定义RIGHTEXTENDWIDTH 8
#定义底部延伸宽度20
#定义TOPEXTENDWIDTH 161
专用插槽：
无效标题（HWND HWND，HDC HDC）；
LRESULT HitTestNCA（HWND HWND，LPARAM LPARAM）；
受保护的：
bool winEvent（MSG*pMessage，long*result）；
私人：
QPixmap；

最后，在cpp文件中：

bool MainWindow::winEvent(MSG *pMessage, long *result)
{
    HWND hWnd = pMessage->hwnd;
    UINT message = pMessage->message;
    WPARAM wParam = pMessage->wParam;
    LPARAM lParam = pMessage->lParam;

    bool retvalue = false;
    LRESULT lRet = 0;

    DwmDefWindowProc(hWnd, message, wParam, lParam, &lRet);

    if (message == WM_ACTIVATE)
    {
        MARGINS margins;

        margins.cxLeftWidth = LEFTEXTENDWIDTH;
        margins.cxRightWidth = RIGHTEXTENDWIDTH;
        margins.cyBottomHeight = BOTTOMEXTENDWIDTH;
        margins.cyTopHeight = TOPEXTENDWIDTH;

        WTA_OPTIONS ops;
        ops.dwFlags = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
        ops.dwMask = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
        SetWindowThemeNonClientAttributes(hWnd, ops.dwMask, ops.dwFlags);

        DwmExtendFrameIntoClientArea(hWnd, &margins);

        lRet = 0;
        retvalue = false;
    }

    if(message == WM_PAINT)
    {
        HDC hDC = GetWindowDC(hWnd);
        PaintCustomCaption(hWnd, hDC);
        DeleteDC(hDC);
        lRet = 0;
        retvalue = true;
    }

    if(message == WM_NCCALCSIZE)
    {
        lRet = 0;
        retvalue = true;
    }

    if(message == WM_NCHITTEST)
    {
        lRet = HitTestNCA(hWnd, lParam);
        DwmDefWindowProc(hWnd, message, wParam, lParam, &lRet);
        retvalue = true;
    }

    *result = lRet;
    if(retvalue) return true;

    return QWidget::winEvent(pMessage, result);
}

void MainWindow::PaintCustomCaption(HWND hWnd, HDC hdc)
{
    RECT rcClient;
    GetClientRect(hWnd, &rcClient);

    HDC hdcPaint = CreateCompatibleDC(hdc);

    HDC hdcRes = CreateCompatibleDC(hdc);

    if (pixmap.isNull()) pixmap = QPixmap("png.png");

    HBITMAP hBmpRes = pixmap.toWinHBITMAP(QPixmap::PremultipliedAlpha);

    SIZE szBmpRes;
    BITMAP rBitmap;
    GetObject(hBmpRes, sizeof (BITMAP), &rBitmap);
    szBmpRes.cx = rBitmap.bmWidth;
    szBmpRes.cy = rBitmap.bmHeight;

    HBITMAP hOldBmpRes = (HBITMAP)SelectObject(hdcRes, hBmpRes);

    if (hdcPaint)
    {
        int cx = rcClient.right - rcClient.left;
        int cy = rcClient.bottom - rcClient.top;

        BITMAPINFO dib = {0};
        dib.bmiHeader.biSize            = sizeof(BITMAPINFOHEADER);
        dib.bmiHeader.biWidth           = cx;
        dib.bmiHeader.biHeight          = -cy;
        dib.bmiHeader.biPlanes          = 1;
        dib.bmiHeader.biBitCount        = 32;
        dib.bmiHeader.biCompression     = BI_RGB;

        HBITMAP hbm = CreateDIBSection(hdc, &dib, DIB_RGB_COLORS, NULL, NULL, 0);

        if (hbm)
        {
            HBITMAP hbmOld = (HBITMAP)SelectObject(hdcPaint, hbm);
            BitBlt(hdcPaint, 0, 0, cx, cy, hdcRes, 0, 0, SRCCOPY);
            BitBlt(hdc, 0, 0, cx, cy, hdcPaint, 0, 0, SRCCOPY);
            SelectObject(hdcPaint, hbmOld);
            DeleteObject(hbm);
        }
        DeleteDC(hdcPaint);
    }
    SelectObject(hdcRes, (HBITMAP)hOldBmpRes);
    DeleteObject(hBmpRes);
    DeleteDC(hdcRes);
}

LRESULT MainWindow::HitTestNCA(HWND hWnd, LPARAM lParam)
{
    POINT ptMouse = {(int)(short)LOWORD(lParam), (int)(short)HIWORD(lParam)};

    RECT rcWindow;
    GetWindowRect(hWnd, &rcWindow);

    RECT rcFrame = { 0 };
    AdjustWindowRectEx(&rcFrame, WS_OVERLAPPEDWINDOW & ~WS_CAPTION, FALSE, NULL);

    USHORT uRow = 1;
    USHORT uCol = 1;
    bool fOnResizeBorder = false;

    if (ptMouse.y >= rcWindow.top && ptMouse.y < rcWindow.top + TOPEXTENDWIDTH)
    {
        fOnResizeBorder = (ptMouse.y < (rcWindow.top - rcFrame.top));
        uRow = 0;
    }
    else if (ptMouse.y < rcWindow.bottom && ptMouse.y >= rcWindow.bottom - BOTTOMEXTENDWIDTH)
    {
        uRow = 2;
    }

    if (ptMouse.x >= rcWindow.left && ptMouse.x < rcWindow.left + LEFTEXTENDWIDTH)
    {
        uCol = 0;
    }
    else if (ptMouse.x < rcWindow.right && ptMouse.x >= rcWindow.right - RIGHTEXTENDWIDTH)
    {
        uCol = 2;
    }

    LRESULT hitTests[3][3] =
    {
        { HTTOPLEFT,    fOnResizeBorder ? HTTOP : HTCAPTION,    HTTOPRIGHT },
        { HTLEFT,       HTNOWHERE,     HTRIGHT },
        { HTBOTTOMLEFT, HTBOTTOM, HTBOTTOMRIGHT },
    };

    return hitTests[uRow][uCol];
}

bool主窗口：：winEvent（MSG*pMessage，long*result）
{
HWND HWND=pMessage->HWND；
UINT message=pMessage->message；
WPARAM WPARAM=pMessage->WPARAM；
LPARAM LPARAM=pMessage->LPARAM；
bool-retvalue=false；
LRESULT lRet=0；
DwmDefWindowProc（hWnd、message、wParam、lParam和lRet）；
如果（消息==WM\U激活）
{
利润率；
margins.cxLeftWidth=LEFTEXTENDWIDTH；
margins.cxRightWidth=RIGHTEXTENDWIDTH；
margins.cyBottomHeight=底部延伸宽度；
margins.height=TOPEXTENDWIDTH；
WTA_选项操作；
ops.dwFlags=WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON；
ops.dwMask=WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON；
设置WindowTheMeNonClientAttributes（hWnd、ops.dwMask、ops.dwFlags）；
DwmExtendFrameIntoClientArea（硬件和边缘）；
lRet=0；
retvalue=false；
}
如果（消息==WM\U PAINT）
{
HDC HDC=GetWindowDC（hWnd）；
自定义标题（hWnd、hDC）；
DeleteDC（hDC）；
lRet=0；
retvalue=true；
}
如果（消息==WM\u NCCALCSIZE）
{
lRet=0；
retvalue=true；
}
如果（消息==WM_NCHITTEST）
{
lRet=HitTestNCA（hWnd，lParam）；
DwmDefWindowProc（hWnd、message、wParam、lParam和lRet）；
retvalue=true；
}
*结果=lRet；
if（retvalue）返回true；
返回QWidget:：winEvent（pMessage，result）；
}
void主窗口：：PaintCustomCaption（HWND HWND，HDC HDC）
{
RECT-rcClient；
GetClientRect（hWnd和rcClient）；
HDC hdcPaint=CreateCompatibleDC（HDC）；
HDC hdcRes=创建兼容的数据中心（HDC）；
如果（pixmap.isNull（））pixmap=QPixmap（“png.png”）；
HBITMAP hBmpRes=pixmap.towinhbmap（QPixmap:：premultipledalpha）；
大小szBmpRes；
位图rBitmap；
GetObject（hBmpRes、sizeof（位图）和rBitmap）；
szBmpRes.cx=rBitmap.bmWidth；
szBmpRes.cy=rBitmap.bmHeight；
HBITMAP hOldBmpRes=（HBITMAP）SelectObject（hdcRes，hBmpRes）；
if（hdcPaint）
{
int cx=rcClient.right-rcClient.left；
int cy=rcClient.bottom-rcClient.top；
BITMAPINFO dib={0}；
dib.bmiHeader.biSize=sizeof（BitMapInfo头文件）；
dib.bmiHeader.biWidth=cx；
dib.bmiHeader.biHeight=-cy；
dib.bmiHeader.biPlanes=1；
dib.bmiHeader.biBitCount=32；
dib.bmiHeader.biCompression=BI_RGB；
HBITMAP hbm=CreateDIBSection（hdc，&dib，dib_RGB_颜色，NULL，NULL，0）；
如果（hbm）
{
HBITMAP hbmOld=（HBITMAP）SelectObject（hdcPaint，hbm）；
BitBlt（hdcPaint，0，0，cx，cy，hdcRes，0，0，SRCCOPY）；
BitBlt（hdc，0，0，cx，cy，hdcPaint，0，0，SRCCOPY）；
选择对象（hdcPaint、hbmOld）；
删除对象（hbm）；
}
DeleteDC（hdcPaint）；
}
选择对象（hdcRes，（HBITMAP）hOldBmpRes）；
删除对象（hBmpRes）；
DeleteDC（hdcRes）；
}
LRESULT主窗口：：HitTestNCA（HWND HWND，LPARAM LPARAM）
{
点ptMouse={（int）（short）LOWORD（lParam），（int）（short）HIWORD（lParam）}；
矩形窗口；
GetWindowRect（hWnd和rcWindow）；
RECT rcFrame={0}；
AdjustWindowRectEx（&rcFrame，WS\u重叠窗口和~WS\u标题，FALSE，NULL）；
USHORT-uRow=1；
USHORT-uCol=1；
bool-fOnResizeBorder=false；
if（ptMouse.y>=rcWindow.top&&ptMouse.y=rcWindow.bottom-BOTTOMEXTENDWIDTH）
{
uRow=2；
}
if（ptMouse.x>=rcWindow.left&&ptMouse.x=rcWindow.right-rightedwidth）
{
uCol=2；
}
LRESULT hitTests[3][3]=
{
{httoplight，fOnResizeBorder？HTTOP:HTCAPTION，httoplight}，
{HTLEFT，HTNOWHERE，HTRIGHT}，
{HTBOTTOMLEFT，HTBOTTOM，HTBOTTOMRIGHT}，
};
返回测试[uRow][uCol]；
}

几次尝试后，我将此代码写入代码，以绘制一个图像，该图像在Qt窗口的非客户端区域扩展，并在Windows 7下进行测试

结果截图：

及有关守则：

在.pro文件中：

LIBS += -lGdi32
LIBS += -lUser32
LIBS += -lDwmApi
LIBS += -lUxTheme

在头文件中：

#include <dwmapi.h>

#define LEFTEXTENDWIDTH 8
#define RIGHTEXTENDWIDTH 8
#define BOTTOMEXTENDWIDTH 20
#define TOPEXTENDWIDTH 161

private slots:
    void PaintCustomCaption(HWND hWnd, HDC hdc);
    LRESULT HitTestNCA(HWND hWnd, LPARAM lParam);

protected:
    bool winEvent(MSG *pMessage, long *result);

private:
    QPixmap pixmap;

#包括
#定义LEFTEXTENDWIDTH 8
#定义RIGHTEXTENDWIDTH 8
#定义底部延伸宽度20
#定义TOPEXTENDWIDTH 161
专用插槽：
无效标题（HWND HWND，HDC HDC）；
LRESULT HitTestNCA（HWND HWND，LPARAM LPARAM）；
受保护的：
bool winEvent（MSG*pMessage，long*result）；
私人：
QPixmap；

最后，在cpp文件中：

bool MainWindow::winEvent(MSG *pMessage, long *result)
{
    HWND hWnd = pMessage->hwnd;
    UINT message = pMessage->message;
    WPARAM wParam = pMessage->wParam;
    LPARAM lParam = pMessage->lParam;

    bool retvalue = false;
    LRESULT lRet = 0;

    DwmDefWindowProc(hWnd, message, wParam, lParam, &lRet);

    if (message == WM_ACTIVATE)
    {
        MARGINS margins;

        margins.cxLeftWidth = LEFTEXTENDWIDTH;
        margins.cxRightWidth = RIGHTEXTENDWIDTH;
        margins.cyBottomHeight = BOTTOMEXTENDWIDTH;
        margins.cyTopHeight = TOPEXTENDWIDTH;

        WTA_OPTIONS ops;
        ops.dwFlags = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
        ops.dwMask = WTNCA_NODRAWCAPTION | WTNCA_NODRAWICON;
        SetWindowThemeNonClientAttributes(hWnd, ops.dwMask, ops.dwFlags);

        DwmExtendFrameIntoClientArea(hWnd, &margins);

        lRet = 0;
        retvalue = false;
    }

    if(message == WM_PAINT)
    {
        HDC hDC = GetWindowDC(hWnd);
        PaintCustomCaption(hWnd, hDC);
        DeleteDC(hDC);
        lRet = 0;
        retvalue = true;
    }

    if(message == WM_NCCALCSIZE)
    {
        lRet = 0;
        retvalue = true;
    }

    if(message == WM_NCHITTEST)
    {
        lRet = HitTestNCA(hWnd, lParam);
        DwmDefWindowProc(hWnd, message, wParam, lParam, &lRet);
        retvalue = true;
    }

    *result = lRet;
    if(retvalue) return true;

    return QWidget::winEvent(pMessage, result);
}

void MainWindow::PaintCustomCaption(HWND hWnd, HDC hdc)
{
    RECT rcClient;
    GetClientRect(hWnd, &rcClient);

    HDC hdcPaint = CreateCompatibleDC(hdc);

    HDC hdcRes = CreateCompatibleDC(hdc);

    if (pixmap.isNull()) pixmap = QPixmap("png.png");

    HBITMAP hBmpRes = pixmap.toWinHBITMAP(QPixmap::PremultipliedAlpha);

    SIZE szBmpRes;
    BITMAP rBitmap;
    GetObject(hBmpRes, sizeof (BITMAP), &rBitmap);
    szBmpRes.cx = rBitmap.bmWidth;
    szBmpRes.cy = rBitmap.bmHeight;

    HBITMAP hOldBmpRes = (HBITMAP)SelectObject(hdcRes, hBmpRes);

    if (hdcPaint)
    {
        int cx = rcClient.right - rcClient.left;
        int cy = rcClient.bottom - rcClient.top;

        BITMAPINFO dib = {0};
        dib.bmiHeader.biSize            = sizeof(BITMAPINFOHEADER);
        dib.bmiHeader.biWidth           = cx;
        dib.bmiHeader.biHeight          = -cy;
        dib.bmiHeader.biPlanes          = 1;
        dib.bmiHeader.biBitCount        = 32;
        dib.bmiHeader.biCompression     = BI_RGB;

        HBITMAP hbm = CreateDIBSection(hdc, &dib, DIB_RGB_COLORS, NULL, NULL, 0);

        if (hbm)
        {
            HBITMAP hbmOld = (HBITMAP)SelectObject(hdcPaint, hbm);
            BitBlt(hdcPaint, 0, 0, cx, cy, hdcRes, 0, 0, SRCCOPY);
            BitBlt(hdc, 0, 0, cx, cy, hdcPaint, 0, 0, SRCCOPY);
            SelectObject(hdcPaint, hbmOld);
            DeleteObject(hbm);
        }
        DeleteDC(hdcPaint);
    }
    SelectObject(hdcRes, (HBITMAP)hOldBmpRes);
    DeleteObject(hBmpRes);
    DeleteDC(hdcRes);
}

LRESULT MainWindow::HitTestNCA(HWND hWnd, LPARAM lParam)
{
    POINT ptMouse = {(int)(short)LOWORD(lParam), (int)(short)HIWORD(lParam)};

    RECT rcWindow;
    GetWindowRect(hWnd, &rcWindow);

    RECT rcFrame = { 0 };
    AdjustWindowRectEx(&rcFrame, WS_OVERLAPPEDWINDOW & ~WS_CAPTION, FALSE, NULL);

    USHORT uRow = 1;
    USHORT uCol = 1;
    bool fOnResizeBorder = false;

    if (ptMouse.y >= rcWindow.top && ptMouse.y < rcWindow.top + TOPEXTENDWIDTH)
    {
        fOnResizeBorder = (ptMouse.y < (rcWindow.top - rcFrame.top));
        uRow = 0;
    }
    else if (ptMouse.y < rcWindow.bottom && ptMouse.y >= rcWindow.bottom - BOTTOMEXTENDWIDTH)
    {
        uRow = 2;
    }

    if (ptMouse.x >= rcWindow.left && ptMouse.x < rcWindow.left + LEFTEXTENDWIDTH)
    {
        uCol = 0;
    }
    else if (ptMouse.x < rcWindow.right && ptMouse.x >= rcWindow.right - RIGHTEXTENDWIDTH)
    {
        uCol = 2;
    }

    LRESULT hitTests[3][3] =
    {
        { HTTOPLEFT,    fOnResizeBorder ? HTTOP : HTCAPTION,    HTTOPRIGHT },
        { HTLEFT,       HTNOWHERE,     HTRIGHT },
        { HTBOTTOMLEFT, HTBOTTOM, HTBOTTOMRIGHT },
    };

    return hitTests[uRow][uCol];
}

bool主窗口：：winEvent（MSG*pMessage，long*result）
{
HWND HWND=pMessage->HWND；
UINT message=pMessage->messa