QT 实现在一个模块中间显示一个红色提示框，3秒后消失

#include "dialog.h"

#include "ui_dialog.h"

#include 

#include 

Dialog::Dialog(QWidget *parent) :

    QDialog(parent),

    ui(new Ui::Dialog),

    label(new QLabel(this))

{

    ui->setupUi(this);

}

Dialog::~Dialog()

{

    delete ui;

}

void Dialog::on_toolButton_clicked()

{

    showFinished();

    QTimer::singleShot(3000, this, SLOT(slotHideFinishedLabel()));  // 这里是一个3秒定时器， 且只执行一次。

}

//下面这是提示框隐藏

void Dialog::slotHideFinishedLabel()

{

    label->hide();

    this->close();

}

//下面这个红色提示框显示

void Dialog::showFinished()

{

    QRect rect = geometry();

    label->setMaximumWidth(500);

    label->setMaximumHeight(50);

    label->setMinimumWidth(500);

    label->setMinimumHeight(50);

    QFont font;

    font.setPointSize(25);

    label->setFont(font);

    label->setStyleSheet(QLatin1String("color:red;"));

    label->setText("The answer end of time!");

    label->setGeometry(int((rect.width()-label->width())/2), int((rect.height()-label->height())/2), label->width(), label->height());

    label->show();

}