启动画面

#include "mainwindow.h"
#include 
#include 

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QPixmap pixmap(":/new/prefix1/image/back.jpg");
    QSplashScreen splash(pixmap);  //启动画面类
    splash.show();

    MainWindow w;
    w.show();
    splash.finish(&w); //Makes the splash screen wait until the widget mainWin is displayed 

    return a.exec();
}

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#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    sleep(1000);  //延时1s，即启动画面持续1s，之后启动程序
}

MainWindow::~MainWindow()
{
    delete ui;
}

/**
 * @brief 延时函数
 * @param msec
 */
void MainWindow::sleep(unsigned int msec)
{
    QTime dieTime = QTime::currentTime().addMSecs(msec);
    while( QTime::currentTime() < dieTime )
        QCoreApplication::processEvents(QEventLoop::AllEvents, 100);
}