C++ 如何使用WM_NCHITTEST从子窗口移动无边框的父窗口

因此，我创建了这个带有自定义移动和大小的弹出窗口，按ctrl键并单击客户端中的任意位置进行移动，然后在边框处按alt键调整大小。问题是，现在我正在为这个窗口内部创建子窗口，但这里出现了“错误”。我找不到如何将消息发送到父窗口。 这就是我尝试过的

我在父窗口的wndproc中处理这些消息

case WM_NCHITTEST:
    //determines if the window should be moving, sizing or don't do a thing
    return DoHitTest(pWnd, GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam) );

case WM_NCLBUTTONDOWN:
    //just set the cursor for visual notice
if (GetAsyncKeyState(VK_CONTROL) & 0x8000)
    SetCursor(LoadCursor(NULL, IDC_SIZEALL));
break;

这是Dohit测试方法

int WindowGnaq::DoHitTest(WindowBase* pWnd, int x, int y)
{
    if( GetAsyncKeyState( VK_CONTROL ) & 0x8000 )
        return HTCAPTION;

    if( m_bAdjustable && GetAsyncKeyState( VK_MENU ) & 0x8000 )
    {
        short spare = 5;
        RECT r;
        pWnd->GetRect(r);
        r.right -= 1;
        r.bottom -= 1;

        if (x < (r.left + spare) && y < (r.top + spare))
            return HTTOPLEFT;
        else if (x < (r.left + spare) && y > (r.bottom - spare))
            return HTBOTTOMLEFT;
        else if (x < (r.left + spare))
            return HTLEFT;
        else if (x > (r.right - spare) && y < (r.top + spare))
            return HTTOPRIGHT;
        else if (x > (r.right - spare) && y > (r.bottom - spare))
            return HTBOTTOMRIGHT;
        else if (x > (r.right - spare))
            return HTRIGHT;
        else if (y < (r.top + spare))
            return HTTOP;
        else if (y > (r.bottom - spare))
            return HTBOTTOM;
    }
    return HTCLIENT;
}

---

孩子的窗口过程应该返回

HTTRANSPARENT

，以响应

WM\u NCHITTEST

，并且（引用）

“消息将被发送到同一线程中的底层窗口，直到其中一个窗口返回非HTTRANSPARENT的代码为止”

如果我的父窗口和子窗口不在同一线程中，该怎么办？如果

HTTRANSPARENT

返回，则整个窗口将不会响应鼠标。

    case WM_NCHITTEST:
        //this just moves the mouse to the border i don't have but doesn't make me able to move
        return SendMessage( m_pParent->GetHandle(), WM_SYSCOMMAND, SC_MOVE, -1); 
        //this doesn't to anything
        return PostMessage( m_pParent->GetHandle(), msg, wParam, lParam); 

        //this makes the childwindow move instead of the parent
        return SendMessage( m_pParent->GetHandle(), msg, wParam, lParam);