About making a progress bar for software initialization for Qt

为什么

Why make an initialization progress bar for the software？
A slightly larger software,Lots of pages and resources,Only initialize when all resources and pages are in use,Then a slightly larger page will be stuck when it is openedPPT.All pages are initialized when the software is just opened,It can solve the subsequent software freeze problem.But the software is all initialized when it is just opened,配合是openmp创建多个线程,Use multiple threads to quickly complete initialization work,The relevant page functions at this time cannot be too complicated,A progress bar that can indicate the progress of software initialization is the best choice.

说明

I don't have a window that needs to load a lot of resources for the time being,就是用Sleepfunction instead of its function,Implement its initialization function.

效果展示

程序

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QTimer>
namespace Ui {
    
class MainWindow;
}

class MainWindow : public QWidget
{
    
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
signals:
    void ooo();
private slots:
    void on_timerout();
    void on_timerout2();
private:
    Ui::MainWindow *ui;
    QTimer timer;
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <omp.h>
#include <QDebug>
#include <windows.h>
 int count=0;
MainWindow::MainWindow(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::MainWindow)
{
    
    ui->setupUi(this);
    ui->progressBar->setRange(0,70);
    setWindowFlags(Qt::FramelessWindowHint);//隐藏标题栏,remove taskbar,Put the window on top of all windows
    this->setAttribute(Qt::WA_TranslucentBackground);
    connect(&timer,&QTimer::timeout,this,&MainWindow::on_timerout2);
    connect(this,&MainWindow::ooo,this,&MainWindow::on_timerout);
    timer.start(20);
}

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

void MainWindow::on_timerout()
{
    
    ui->progressBar->setValue(count);
    if(count>=70)
        close();
}

void MainWindow::on_timerout2()
{
    
    timer.stop();
#pragma omp parallel for
for (int i = 1; i <= 70; i++)
{
    
    Sleep(1000);
    qDebug() << "Hello World! " << i <<" "<<count<< endl;
    count++;
    ooo();
}
qDebug()<<count<<endl;
}

UIThere is only one progress bar in the file

最后

初始化过程中openmp的forThe number of loops should not be too large,最大保持在50左右,Any higher progress bar will get stuck,出现一个黑框.