Qt设置创建部分半透明，上面控件不透明

//头文件
#pragma once

#include <QWidget>
#include "ui_widgetFullAD.h"

class widgetFullAD : public QWidget
{
    Q_OBJECT

public:
    widgetFullAD(QWidget *parent = Q_NULLPTR);
    ~widgetFullAD();

protected:
    virtual bool eventFilter(QObject *watched, QEvent *event);
    void paintEvent(QPaintEvent *event);
    virtual void mousePressEvent(QMouseEvent *event);

private:
    Ui::widgetFullAD ui;
};

#include "widgetFullAD.h"
#include <qpainter.h>
widgetFullAD::widgetFullAD(QWidget *parent)
    : QWidget(parent)
{
    ui.setupUi(this);
    setAttribute(Qt::WA_TranslucentBackground, true);
    setWindowFlags(Qt::ToolTip | Qt::FramelessWindowHint);
    //ui.widget->installEventFilter(this);
    //installEventFilter(this);
}

widgetFullAD::~widgetFullAD()
{
    int xx = 343;
}

bool widgetFullAD::eventFilter(QObject * watched, QEvent * event)
{

    return QWidget::eventFilter(watched, event);
}

void widgetFullAD::paintEvent(QPaintEvent * event)
{
    QPainter painter(this);
    painter.fillRect(this->rect(), QColor(0, 0, 0, 150));  //QColor最后一个参数80代表背景的透明度
}

void widgetFullAD::mousePressEvent(QMouseEvent * event)
{
    QRect rt = ui.widget->geometry();
    QPoint pt= this->mapFromGlobal(QCursor::pos());//将显示器坐标转换成窗口坐标
    if (ui.widget->geometry().contains(this->mapFromGlobal(QCursor::pos())))
    {

    }
    else
    {
        hide();
    }
}