QT 移入控件展示卡片

功能：移入widget显示卡片，并且可以进入卡片不消失（widget与卡片距离离得很近），移出卡片才离开

bool DataShowWidget::eventFilter(QObject *obj, QEvent *event)
{
    if (obj == ui->widget && event->type() == QEvent::Enter) {
        if (!m_noFollow) {
        	m_noFollow = new NoFollowWidget(this);
    		m_noFollow->installEventFilter(this);
    		// 连接卡片的离开事件
    		connect(m_noFollow, &NoFollowWidget::leaveNoFollow,
            		this, &DataShowWidget::onLeaveNoFollow);
    	}

		// 卡片显示在widget的左下方
    	QPoint pos = ui->widget->mapToGlobal(QPoint(0, 0)) +
                 QPoint(0, ui->widget->height());
    	m_noFollow->move(pos.x(), pos.y());
    	m_noFollow->show();
    	m_noFollow->adjustSize();
    }

    if (obj == ui->widget&& event->type() == QEvent::Leave) {
        if (!m_noFollow) {
            return QWidget::eventFilter(obj, event);
        }

        if (m_noFollow->geometry().contains(QCursor::pos())) {
            return QWidget::eventFilter(obj, event);
        }
        
        m_noFollow->hide();
    }
    return QWidget::eventFilter(obj, event);
}