Qt 实现在隐藏标题栏情况下，窗口的缩放（未成功）

#include <windows.h>

bool Widget::nativeEvent(const QByteArray &eventType, void *message, long *result)
{
    Q_UNUSED(eventType);
    if (this->isMaximized())
    {
        return false;
    }
    const int HIT_BORDER = 5;
    const MSG *msg=static_cast<MSG*>(message);
    if(msg->message == WM_NCHITTEST) {
        int xPos = ((int)(short)LOWORD(msg->lParam)) - this->frameGeometry().x();
        int yPos = ((int)(short)HIWORD(msg->lParam)) - this->frameGeometry().y();
        if(this->childAt(xPos,yPos) == 0) {
            *result = HTCAPTION;
        } else {
            return false;
        }
        if(xPos > 0 && xPos < HIT_BORDER) {
            *result = HTLEFT;
        }
        if(xPos > (this->width() - HIT_BORDER) && xPos < (this->width() - 0)) {
            *result = HTRIGHT;
        }
        if(yPos > 0 && yPos < HIT_BORDER) {
            *result = HTTOP;
        }
        if(yPos > (this->height() - HIT_BORDER) && yPos < (this->height() - 0)) {
            *result = HTBOTTOM;
        }
        if(xPos > 0 && xPos < HIT_BORDER && yPos > 0 && yPos < HIT_BORDER) {
            *result = HTTOPLEFT;
        }
        if(xPos > (this->width() - HIT_BORDER) && xPos < (this->width() - 0) && yPos > 0 && yPos < HIT_BORDER) {
            *result = HTTOPRIGHT;
        }
        if(xPos > 0 && xPos < HIT_BORDER && yPos > (this->height() - HIT_BORDER) && yPos < (this->height() - 0)) {
            *result = HTBOTTOMLEFT;
        }
        if(xPos > (this->width() - HIT_BORDER) && xPos < (this->width() - 0) && yPos > (this->height() - HIT_BORDER) && yPos < (this->height() - 0)) {
            *result = HTBOTTOMRIGHT;
        }
        return true;
    }
    return false;
}