Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. How to save a table in a file
Forum Updated to NodeBB v4.3 + New Features

How to save a table in a file

Scheduled Pinned Locked Moved Unsolved General and Desktop
27 Posts 5 Posters 6.5k Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • D Offline
    D Offline
    Daesos
    wrote on last edited by Daesos
    #5

    The image above is the directory of my project. If I click on save button, the cell corresponding to log_activity.csv and Event changes into modified.
    It shows "Modified" when the date of the previous directory is different from the current one.
    So I guess the save_button works.

    0_1531210402194_729a0dca-9bc9-4745-a532-9d41af2aef78-image.png

    Also, if the file doesn't exit, the program create the file with the given name.

    jsulmJ JonBJ 2 Replies Last reply
    0
    • D Daesos

      I'd like to not implement other libraries. I want to resolve this only with given libraries by Qt.

      VRoninV Offline
      VRoninV Offline
      VRonin
      wrote on last edited by VRonin
      #6

      @Daesos said in How to save a table in a file:

      I want to resolve this only with given libraries by Qt

      Then copy-paste my code. I only use Qt in those and license is apache 2 so you can basically do what you want with it.

      In your code above you are not:

      • Writing any new line to separate rows.
      • Writing any column separator
      • Escaping column separators inside the data

      "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
      ~Napoleon Bonaparte

      On a crusade to banish setIndexWidget() from the holy land of Qt

      1 Reply Last reply
      0
      • D Daesos

        The image above is the directory of my project. If I click on save button, the cell corresponding to log_activity.csv and Event changes into modified.
        It shows "Modified" when the date of the previous directory is different from the current one.
        So I guess the save_button works.

        0_1531210402194_729a0dca-9bc9-4745-a532-9d41af2aef78-image.png

        Also, if the file doesn't exit, the program create the file with the given name.

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #7

        @Daesos Did you try to debug? Especially the nested for loops?

        https://forum.qt.io/topic/113070/qt-code-of-conduct

        D 1 Reply Last reply
        0
        • D Daesos

          The image above is the directory of my project. If I click on save button, the cell corresponding to log_activity.csv and Event changes into modified.
          It shows "Modified" when the date of the previous directory is different from the current one.
          So I guess the save_button works.

          0_1531210402194_729a0dca-9bc9-4745-a532-9d41af2aef78-image.png

          Also, if the file doesn't exit, the program create the file with the given name.

          JonBJ Offline
          JonBJ Offline
          JonB
          wrote on last edited by JonB
          #8

          @Daesos
          Assuming the file is opened for write, you are saying you end up with nothing in it, and your table does indeed contain desired text (ui->tableWidget->item(i, j)->text()). You stream all your data to QTextStream out but you only close the QFile csv. I don't know if that knows to fetch all remaining data out of the stream. Try out.flush() prior to the csv.close()?

          1 Reply Last reply
          1
          • jsulmJ jsulm

            @Daesos Did you try to debug? Especially the nested for loops?

            D Offline
            D Offline
            Daesos
            wrote on last edited by Daesos
            #9

            @jsulm I'm trying, but it stops with this message: Stopped "end-stepping-range". I've put a breakpoint at "out<<ui->tableWidget->item(i, j)->text();" and as i can see, this returns "main.window.cpp", which is correct. Then, I don't what happen.

            jsulmJ 1 Reply Last reply
            0
            • D Daesos

              @jsulm I'm trying, but it stops with this message: Stopped "end-stepping-range". I've put a breakpoint at "out<<ui->tableWidget->item(i, j)->text();" and as i can see, this returns "main.window.cpp", which is correct. Then, I don't what happen.

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on last edited by
              #10

              @Daesos Try calling http://doc.qt.io/qt-5/qtextstream.html#flush before closing the file

              https://forum.qt.io/topic/113070/qt-code-of-conduct

              D 1 Reply Last reply
              0
              • jsulmJ jsulm

                @Daesos Try calling http://doc.qt.io/qt-5/qtextstream.html#flush before closing the file

                D Offline
                D Offline
                Daesos
                wrote on last edited by
                #11

                @jsulm Already did, and nothing changed.

                jsulmJ 1 Reply Last reply
                0
                • D Daesos

                  @jsulm Already did, and nothing changed.

                  jsulmJ Offline
                  jsulmJ Offline
                  jsulm
                  Lifetime Qt Champion
                  wrote on last edited by
                  #12

                  @Daesos Last idea I have: is it possible that you open same file somewhere else in your app, or that there is still an instance of your app running?
                  Oh, one more idea: try to write the file using an absolute path to some other location.

                  https://forum.qt.io/topic/113070/qt-code-of-conduct

                  D 1 Reply Last reply
                  0
                  • jsulmJ jsulm

                    @Daesos Last idea I have: is it possible that you open same file somewhere else in your app, or that there is still an instance of your app running?
                    Oh, one more idea: try to write the file using an absolute path to some other location.

                    D Offline
                    D Offline
                    Daesos
                    wrote on last edited by Daesos
                    #13

                    @jsulm I checked and there is no other instance opened. Also, I used another path. The program created the file.csv (empty), then quitted. Application Output: "The program has unexpectedly finished."

                    Since I don't know if I have mistaken something I will post all the mainwindow.cpp code:

                    #include "mainwindow.h"
                    #include "ui_mainwindow.h"
                    #include <QFileDialog>
                    #include <QFileInfo>
                    #include <QTimer>
                    #include <QDateTime>
                    #include <QFile>
                    #include <QTextStream>
                    
                    MainWindow::MainWindow(QWidget *parent) :
                        QMainWindow(parent),
                        ui(new Ui::MainWindow)
                    {
                        ui->setupUi(this);
                    
                        setWindowTitle("DirectoryMonitor");
                        ui->tableWidget->setColumnCount(4);
                        ui->tableWidget->setHorizontalHeaderLabels(QStringList() << "" << "Filename" << "Event" << "Time");
                    
                        f_name = "log_activity.csv";
                    }
                    
                    MainWindow::~MainWindow()
                    {
                        delete ui;
                    }
                    
                    void MainWindow::on_pushButton_clicked()
                    {
                        ui->tableWidget->clearContents();
                        path = QFileDialog::getExistingDirectory(this, tr("Open Directory"), ".", QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
                        ui->lineEdit->setText(path);
                    
                    QDir dir(path);
                    
                    dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                    dir.setSorting(QDir::Time);
                    list = dir.entryInfoList();
                    
                    for(int i = 0; i < list.size(); ++i){
                            ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                            ui->tableWidget->setItem(i, 1, new QTableWidgetItem(list.at(i).fileName()));
                            ui->tableWidget->setItem(i, 3, new QTableWidgetItem(list.at(i).lastModified().toString()));
                    }
                    
                    int count = 0;
                    
                    for(int i = 0; i < ui->tableWidget->rowCount(); ++i){
                        QTableWidgetItem *itm = ui->tableWidget->item(i, 1);
                        if(itm != 0)
                           ++count;
                    }
                    //rimuovi righe vuote
                    ui->tableWidget->setRowCount(count);
                    
                    QTimer *time = new QTimer(this);
                    
                    connect(time, SIGNAL(timeout()), this, SLOT(changes()));
                    time->start(3000);
                    }
                    
                    void MainWindow::changes()
                    {
                    QDir dir(path);
                    dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                    dir.setSorting(QDir::Time);
                    
                    QFileInfoList newlist = dir.entryInfoList();
                    
                    int index_delete = -1;
                    
                    //caso modified e delete file
                    for(int i = 0; i < list.size(); ++i){
                        int count = 0;
                        for(int j = 0; j < newlist.size(); ++j){
                            if(list.at(i).fileName() == newlist.at(j).fileName()){
                                ++count;
                                if(list.at(i).lastModified() != newlist.at(j).lastModified()){
                                    QTableWidgetItem *itm = new QTableWidgetItem("");
                                    itm->setBackground(QColor(109, 158, 235));
                                    ui->tableWidget->setItem(i, 0, itm);
                                    ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                    ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                }
                            }
                        }
                        if(count == 0){
                            index_delete = i;
                        }
                    }
                    
                    if(index_delete != -1){
                        QTableWidgetItem *itm = new QTableWidgetItem("");
                        itm->setBackground(QColor(224, 102, 99));
                        ui->tableWidget->setItem(index_delete, 0, itm);
                        if(ui->tableWidget->item(index_delete, 2)->text() != "Deleted")
                            ui->tableWidget->setItem(index_delete, 3, new QTableWidgetItem(QDateTime::currentDateTime().toString()));
                        ui->tableWidget->setItem(index_delete, 2, new QTableWidgetItem("Deleted"));
                    }
                    
                    //caso new file
                    int index_new = -1;
                    
                    for(int i = 0; i < newlist.size(); ++i){
                        int count = 0;
                        for(int j = 0; (j < list.size() && count == 0); ++j){
                            if(newlist.at(i).fileName() == list.at(j).fileName())
                                ++count;
                        }
                        if(count == 0)
                            index_new = i;
                    }
                    
                    if(index_new != -1){
                        ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                        QTableWidgetItem *itm = new QTableWidgetItem("");
                        itm->setBackground(QColor(148, 195, 123));
                        ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 0, itm);
                        ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));
                        ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 2, new QTableWidgetItem("Created"));
                        ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 3, new QTableWidgetItem(newlist.at(index_new).lastModified().toString()));
                        list.append(newlist.at(index_new));
                    }
                    }
                    void MainWindow::on_pushButton_2_clicked()
                    {
                    QFile csv(f_name);
                    
                    if(!csv.open(QFile::WriteOnly))
                        return;
                    
                    QTextStream out(&csv);
                    
                    for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                        for (int j = 1; j < ui->tableWidget->columnCount(); j++){
                            QString txt(ui->tableWidget->item(i, j)->text());
                            out<<txt;
                        }
                    out.flush();
                    csv.close();
                    }
                    

                    Sorry for the indentation.
                    This is the declaration of the global variables in mainwindow.h

                    QString path, f_name;
                    QFileInfoList list;
                    
                    jsulmJ J.HilkJ JonBJ 3 Replies Last reply
                    0
                    • D Daesos

                      @jsulm I checked and there is no other instance opened. Also, I used another path. The program created the file.csv (empty), then quitted. Application Output: "The program has unexpectedly finished."

                      Since I don't know if I have mistaken something I will post all the mainwindow.cpp code:

                      #include "mainwindow.h"
                      #include "ui_mainwindow.h"
                      #include <QFileDialog>
                      #include <QFileInfo>
                      #include <QTimer>
                      #include <QDateTime>
                      #include <QFile>
                      #include <QTextStream>
                      
                      MainWindow::MainWindow(QWidget *parent) :
                          QMainWindow(parent),
                          ui(new Ui::MainWindow)
                      {
                          ui->setupUi(this);
                      
                          setWindowTitle("DirectoryMonitor");
                          ui->tableWidget->setColumnCount(4);
                          ui->tableWidget->setHorizontalHeaderLabels(QStringList() << "" << "Filename" << "Event" << "Time");
                      
                          f_name = "log_activity.csv";
                      }
                      
                      MainWindow::~MainWindow()
                      {
                          delete ui;
                      }
                      
                      void MainWindow::on_pushButton_clicked()
                      {
                          ui->tableWidget->clearContents();
                          path = QFileDialog::getExistingDirectory(this, tr("Open Directory"), ".", QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
                          ui->lineEdit->setText(path);
                      
                      QDir dir(path);
                      
                      dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                      dir.setSorting(QDir::Time);
                      list = dir.entryInfoList();
                      
                      for(int i = 0; i < list.size(); ++i){
                              ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                              ui->tableWidget->setItem(i, 1, new QTableWidgetItem(list.at(i).fileName()));
                              ui->tableWidget->setItem(i, 3, new QTableWidgetItem(list.at(i).lastModified().toString()));
                      }
                      
                      int count = 0;
                      
                      for(int i = 0; i < ui->tableWidget->rowCount(); ++i){
                          QTableWidgetItem *itm = ui->tableWidget->item(i, 1);
                          if(itm != 0)
                             ++count;
                      }
                      //rimuovi righe vuote
                      ui->tableWidget->setRowCount(count);
                      
                      QTimer *time = new QTimer(this);
                      
                      connect(time, SIGNAL(timeout()), this, SLOT(changes()));
                      time->start(3000);
                      }
                      
                      void MainWindow::changes()
                      {
                      QDir dir(path);
                      dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                      dir.setSorting(QDir::Time);
                      
                      QFileInfoList newlist = dir.entryInfoList();
                      
                      int index_delete = -1;
                      
                      //caso modified e delete file
                      for(int i = 0; i < list.size(); ++i){
                          int count = 0;
                          for(int j = 0; j < newlist.size(); ++j){
                              if(list.at(i).fileName() == newlist.at(j).fileName()){
                                  ++count;
                                  if(list.at(i).lastModified() != newlist.at(j).lastModified()){
                                      QTableWidgetItem *itm = new QTableWidgetItem("");
                                      itm->setBackground(QColor(109, 158, 235));
                                      ui->tableWidget->setItem(i, 0, itm);
                                      ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                      ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                  }
                              }
                          }
                          if(count == 0){
                              index_delete = i;
                          }
                      }
                      
                      if(index_delete != -1){
                          QTableWidgetItem *itm = new QTableWidgetItem("");
                          itm->setBackground(QColor(224, 102, 99));
                          ui->tableWidget->setItem(index_delete, 0, itm);
                          if(ui->tableWidget->item(index_delete, 2)->text() != "Deleted")
                              ui->tableWidget->setItem(index_delete, 3, new QTableWidgetItem(QDateTime::currentDateTime().toString()));
                          ui->tableWidget->setItem(index_delete, 2, new QTableWidgetItem("Deleted"));
                      }
                      
                      //caso new file
                      int index_new = -1;
                      
                      for(int i = 0; i < newlist.size(); ++i){
                          int count = 0;
                          for(int j = 0; (j < list.size() && count == 0); ++j){
                              if(newlist.at(i).fileName() == list.at(j).fileName())
                                  ++count;
                          }
                          if(count == 0)
                              index_new = i;
                      }
                      
                      if(index_new != -1){
                          ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                          QTableWidgetItem *itm = new QTableWidgetItem("");
                          itm->setBackground(QColor(148, 195, 123));
                          ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 0, itm);
                          ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));
                          ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 2, new QTableWidgetItem("Created"));
                          ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 3, new QTableWidgetItem(newlist.at(index_new).lastModified().toString()));
                          list.append(newlist.at(index_new));
                      }
                      }
                      void MainWindow::on_pushButton_2_clicked()
                      {
                      QFile csv(f_name);
                      
                      if(!csv.open(QFile::WriteOnly))
                          return;
                      
                      QTextStream out(&csv);
                      
                      for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                          for (int j = 1; j < ui->tableWidget->columnCount(); j++){
                              QString txt(ui->tableWidget->item(i, j)->text());
                              out<<txt;
                          }
                      out.flush();
                      csv.close();
                      }
                      

                      Sorry for the indentation.
                      This is the declaration of the global variables in mainwindow.h

                      QString path, f_name;
                      QFileInfoList list;
                      
                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #14

                      @Daesos Start your app with debugger (F5) and when it crashes check the stack trace to see where it crashes (use debug build of your app).

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      1 Reply Last reply
                      0
                      • D Daesos

                        @jsulm I checked and there is no other instance opened. Also, I used another path. The program created the file.csv (empty), then quitted. Application Output: "The program has unexpectedly finished."

                        Since I don't know if I have mistaken something I will post all the mainwindow.cpp code:

                        #include "mainwindow.h"
                        #include "ui_mainwindow.h"
                        #include <QFileDialog>
                        #include <QFileInfo>
                        #include <QTimer>
                        #include <QDateTime>
                        #include <QFile>
                        #include <QTextStream>
                        
                        MainWindow::MainWindow(QWidget *parent) :
                            QMainWindow(parent),
                            ui(new Ui::MainWindow)
                        {
                            ui->setupUi(this);
                        
                            setWindowTitle("DirectoryMonitor");
                            ui->tableWidget->setColumnCount(4);
                            ui->tableWidget->setHorizontalHeaderLabels(QStringList() << "" << "Filename" << "Event" << "Time");
                        
                            f_name = "log_activity.csv";
                        }
                        
                        MainWindow::~MainWindow()
                        {
                            delete ui;
                        }
                        
                        void MainWindow::on_pushButton_clicked()
                        {
                            ui->tableWidget->clearContents();
                            path = QFileDialog::getExistingDirectory(this, tr("Open Directory"), ".", QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
                            ui->lineEdit->setText(path);
                        
                        QDir dir(path);
                        
                        dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                        dir.setSorting(QDir::Time);
                        list = dir.entryInfoList();
                        
                        for(int i = 0; i < list.size(); ++i){
                                ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                                ui->tableWidget->setItem(i, 1, new QTableWidgetItem(list.at(i).fileName()));
                                ui->tableWidget->setItem(i, 3, new QTableWidgetItem(list.at(i).lastModified().toString()));
                        }
                        
                        int count = 0;
                        
                        for(int i = 0; i < ui->tableWidget->rowCount(); ++i){
                            QTableWidgetItem *itm = ui->tableWidget->item(i, 1);
                            if(itm != 0)
                               ++count;
                        }
                        //rimuovi righe vuote
                        ui->tableWidget->setRowCount(count);
                        
                        QTimer *time = new QTimer(this);
                        
                        connect(time, SIGNAL(timeout()), this, SLOT(changes()));
                        time->start(3000);
                        }
                        
                        void MainWindow::changes()
                        {
                        QDir dir(path);
                        dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                        dir.setSorting(QDir::Time);
                        
                        QFileInfoList newlist = dir.entryInfoList();
                        
                        int index_delete = -1;
                        
                        //caso modified e delete file
                        for(int i = 0; i < list.size(); ++i){
                            int count = 0;
                            for(int j = 0; j < newlist.size(); ++j){
                                if(list.at(i).fileName() == newlist.at(j).fileName()){
                                    ++count;
                                    if(list.at(i).lastModified() != newlist.at(j).lastModified()){
                                        QTableWidgetItem *itm = new QTableWidgetItem("");
                                        itm->setBackground(QColor(109, 158, 235));
                                        ui->tableWidget->setItem(i, 0, itm);
                                        ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                        ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                    }
                                }
                            }
                            if(count == 0){
                                index_delete = i;
                            }
                        }
                        
                        if(index_delete != -1){
                            QTableWidgetItem *itm = new QTableWidgetItem("");
                            itm->setBackground(QColor(224, 102, 99));
                            ui->tableWidget->setItem(index_delete, 0, itm);
                            if(ui->tableWidget->item(index_delete, 2)->text() != "Deleted")
                                ui->tableWidget->setItem(index_delete, 3, new QTableWidgetItem(QDateTime::currentDateTime().toString()));
                            ui->tableWidget->setItem(index_delete, 2, new QTableWidgetItem("Deleted"));
                        }
                        
                        //caso new file
                        int index_new = -1;
                        
                        for(int i = 0; i < newlist.size(); ++i){
                            int count = 0;
                            for(int j = 0; (j < list.size() && count == 0); ++j){
                                if(newlist.at(i).fileName() == list.at(j).fileName())
                                    ++count;
                            }
                            if(count == 0)
                                index_new = i;
                        }
                        
                        if(index_new != -1){
                            ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                            QTableWidgetItem *itm = new QTableWidgetItem("");
                            itm->setBackground(QColor(148, 195, 123));
                            ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 0, itm);
                            ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));
                            ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 2, new QTableWidgetItem("Created"));
                            ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 3, new QTableWidgetItem(newlist.at(index_new).lastModified().toString()));
                            list.append(newlist.at(index_new));
                        }
                        }
                        void MainWindow::on_pushButton_2_clicked()
                        {
                        QFile csv(f_name);
                        
                        if(!csv.open(QFile::WriteOnly))
                            return;
                        
                        QTextStream out(&csv);
                        
                        for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                            for (int j = 1; j < ui->tableWidget->columnCount(); j++){
                                QString txt(ui->tableWidget->item(i, j)->text());
                                out<<txt;
                            }
                        out.flush();
                        csv.close();
                        }
                        

                        Sorry for the indentation.
                        This is the declaration of the global variables in mainwindow.h

                        QString path, f_name;
                        QFileInfoList list;
                        
                        J.HilkJ Offline
                        J.HilkJ Offline
                        J.Hilk
                        Moderators
                        wrote on last edited by
                        #15

                        @Daesos
                        Going through your code, I noticed, you're mixing postfix, prefix in your nested loop to access the Tablewidget Item. I would search there for an out of bounds error.


                        Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                        Q: What's that?
                        A: It's blue light.
                        Q: What does it do?
                        A: It turns blue.

                        1 Reply Last reply
                        1
                        • D Daesos

                          @jsulm I checked and there is no other instance opened. Also, I used another path. The program created the file.csv (empty), then quitted. Application Output: "The program has unexpectedly finished."

                          Since I don't know if I have mistaken something I will post all the mainwindow.cpp code:

                          #include "mainwindow.h"
                          #include "ui_mainwindow.h"
                          #include <QFileDialog>
                          #include <QFileInfo>
                          #include <QTimer>
                          #include <QDateTime>
                          #include <QFile>
                          #include <QTextStream>
                          
                          MainWindow::MainWindow(QWidget *parent) :
                              QMainWindow(parent),
                              ui(new Ui::MainWindow)
                          {
                              ui->setupUi(this);
                          
                              setWindowTitle("DirectoryMonitor");
                              ui->tableWidget->setColumnCount(4);
                              ui->tableWidget->setHorizontalHeaderLabels(QStringList() << "" << "Filename" << "Event" << "Time");
                          
                              f_name = "log_activity.csv";
                          }
                          
                          MainWindow::~MainWindow()
                          {
                              delete ui;
                          }
                          
                          void MainWindow::on_pushButton_clicked()
                          {
                              ui->tableWidget->clearContents();
                              path = QFileDialog::getExistingDirectory(this, tr("Open Directory"), ".", QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks);
                              ui->lineEdit->setText(path);
                          
                          QDir dir(path);
                          
                          dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                          dir.setSorting(QDir::Time);
                          list = dir.entryInfoList();
                          
                          for(int i = 0; i < list.size(); ++i){
                                  ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                                  ui->tableWidget->setItem(i, 1, new QTableWidgetItem(list.at(i).fileName()));
                                  ui->tableWidget->setItem(i, 3, new QTableWidgetItem(list.at(i).lastModified().toString()));
                          }
                          
                          int count = 0;
                          
                          for(int i = 0; i < ui->tableWidget->rowCount(); ++i){
                              QTableWidgetItem *itm = ui->tableWidget->item(i, 1);
                              if(itm != 0)
                                 ++count;
                          }
                          //rimuovi righe vuote
                          ui->tableWidget->setRowCount(count);
                          
                          QTimer *time = new QTimer(this);
                          
                          connect(time, SIGNAL(timeout()), this, SLOT(changes()));
                          time->start(3000);
                          }
                          
                          void MainWindow::changes()
                          {
                          QDir dir(path);
                          dir.setFilter(QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot);
                          dir.setSorting(QDir::Time);
                          
                          QFileInfoList newlist = dir.entryInfoList();
                          
                          int index_delete = -1;
                          
                          //caso modified e delete file
                          for(int i = 0; i < list.size(); ++i){
                              int count = 0;
                              for(int j = 0; j < newlist.size(); ++j){
                                  if(list.at(i).fileName() == newlist.at(j).fileName()){
                                      ++count;
                                      if(list.at(i).lastModified() != newlist.at(j).lastModified()){
                                          QTableWidgetItem *itm = new QTableWidgetItem("");
                                          itm->setBackground(QColor(109, 158, 235));
                                          ui->tableWidget->setItem(i, 0, itm);
                                          ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                          ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                      }
                                  }
                              }
                              if(count == 0){
                                  index_delete = i;
                              }
                          }
                          
                          if(index_delete != -1){
                              QTableWidgetItem *itm = new QTableWidgetItem("");
                              itm->setBackground(QColor(224, 102, 99));
                              ui->tableWidget->setItem(index_delete, 0, itm);
                              if(ui->tableWidget->item(index_delete, 2)->text() != "Deleted")
                                  ui->tableWidget->setItem(index_delete, 3, new QTableWidgetItem(QDateTime::currentDateTime().toString()));
                              ui->tableWidget->setItem(index_delete, 2, new QTableWidgetItem("Deleted"));
                          }
                          
                          //caso new file
                          int index_new = -1;
                          
                          for(int i = 0; i < newlist.size(); ++i){
                              int count = 0;
                              for(int j = 0; (j < list.size() && count == 0); ++j){
                                  if(newlist.at(i).fileName() == list.at(j).fileName())
                                      ++count;
                              }
                              if(count == 0)
                                  index_new = i;
                          }
                          
                          if(index_new != -1){
                              ui->tableWidget->insertRow(ui->tableWidget->rowCount());
                              QTableWidgetItem *itm = new QTableWidgetItem("");
                              itm->setBackground(QColor(148, 195, 123));
                              ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 0, itm);
                              ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));
                              ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 2, new QTableWidgetItem("Created"));
                              ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 3, new QTableWidgetItem(newlist.at(index_new).lastModified().toString()));
                              list.append(newlist.at(index_new));
                          }
                          }
                          void MainWindow::on_pushButton_2_clicked()
                          {
                          QFile csv(f_name);
                          
                          if(!csv.open(QFile::WriteOnly))
                              return;
                          
                          QTextStream out(&csv);
                          
                          for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                              for (int j = 1; j < ui->tableWidget->columnCount(); j++){
                                  QString txt(ui->tableWidget->item(i, j)->text());
                                  out<<txt;
                              }
                          out.flush();
                          csv.close();
                          }
                          

                          Sorry for the indentation.
                          This is the declaration of the global variables in mainwindow.h

                          QString path, f_name;
                          QFileInfoList list;
                          
                          JonBJ Offline
                          JonBJ Offline
                          JonB
                          wrote on last edited by JonB
                          #16

                          @Daesos
                          If you're still having problems with the file (once you've solved the "crash"), try replacing your QFile with a QString, and use https://doc.qt.io/Qt-5/qtextstream.html#QTextStream-3. You should be successfully building up the string of the file content. If that doesn't work, nor will write to file.

                          1 Reply Last reply
                          0
                          • D Offline
                            D Offline
                            Daesos
                            wrote on last edited by Daesos
                            #17

                            I used debugger and when i click on pushButton_2 (save on interface) it returns a Segmentation Fault at "QTableWidgetItem::text".
                            @J.Hilk, I didn't even notice. I edited the increment.

                            Segmentation Fault occurs when I try to access to a NULL pointer, right? So, it might be out of bound.

                            JonBJ 1 Reply Last reply
                            0
                            • D Daesos

                              I used debugger and when i click on pushButton_2 (save on interface) it returns a Segmentation Fault at "QTableWidgetItem::text".
                              @J.Hilk, I didn't even notice. I edited the increment.

                              Segmentation Fault occurs when I try to access to a NULL pointer, right? So, it might be out of bound.

                              JonBJ Offline
                              JonBJ Offline
                              JonB
                              wrote on last edited by JonB
                              #18

                              @Daesos
                              I don't see save_button in the code you've posted?

                              I notice you have:

                                              ui->tableWidget->setItem(i, 0, itm);
                                              ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                              ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                              

                              Where do you setItem() on i, 1 ?

                              for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                                  for (int j = 1; j < ui->tableWidget->columnCount(); j++){
                                      QString txt(ui->tableWidget->item(i, j)->text());
                                      out<<txt;
                                  }
                              

                              Check your accesses on every i, j here. Somewhere you do not have an item at item(i, j)!

                              1 Reply Last reply
                              0
                              • D Offline
                                D Offline
                                Daesos
                                wrote on last edited by Daesos
                                #19

                                I've edited the increment:

                                   for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                                       for (int j = 1; j < ui->tableWidget->columnCount(); ++j)
                                           out<<ui->tableWidget->item(i, j)->text();
                                

                                @JonB said in How to save a table in a file:

                                @Daesos

                                I notice you have:

                                                ui->tableWidget->setItem(i, 0, itm);
                                                ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                                ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                

                                Where do you setItem() on i, 1 ?

                                I've inizialized item at (i, 1) before. Once inizialized the name of the file must not be modified. So I didn't use setItem on i, 1 again.

                                @Daesos
                                ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));

                                J.HilkJ 1 Reply Last reply
                                0
                                • D Daesos

                                  I've edited the increment:

                                     for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                                         for (int j = 1; j < ui->tableWidget->columnCount(); ++j)
                                             out<<ui->tableWidget->item(i, j)->text();
                                  

                                  @JonB said in How to save a table in a file:

                                  @Daesos

                                  I notice you have:

                                                  ui->tableWidget->setItem(i, 0, itm);
                                                  ui->tableWidget->setItem(i, 2, new QTableWidgetItem("Modified"));
                                                  ui->tableWidget->setItem(i, 3, new QTableWidgetItem(newlist.at(j).lastModified().toString()));
                                  

                                  Where do you setItem() on i, 1 ?

                                  I've inizialized item at (i, 1) before. Once inizialized the name of the file must not be modified. So I didn't use setItem on i, 1 again.

                                  @Daesos
                                  ui->tableWidget->setItem(ui->tableWidget->rowCount() - 1, 1, new QTableWidgetItem(newlist.at(index_new).fileName()));

                                  J.HilkJ Offline
                                  J.HilkJ Offline
                                  J.Hilk
                                  Moderators
                                  wrote on last edited by
                                  #20

                                  @Daesos said in How to save a table in a file:

                                  for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                                  for (int j = 1; j < ui->tableWidget->columnCount(); ++j)
                                  out<<ui->tableWidget->item(i, j)->text();

                                  Maybe it's time to #include good old <QDebug>

                                  for(int i = 0; i < ui->tableWidget->rowCount(); ++i)
                                         for (int j = 1; j < ui->tableWidget->columnCount(); ++j){
                                             qDebug() << i << "of" << ui->tableWidget->rowCount() << endl
                                                               << j << "of" << ui->tableWidget->columnCount();
                                             out<<ui->tableWidget->item(i, j)->text();
                                             qDebug() << QString("Found text at %1 | %2").arg(i).arg(j);
                                         }
                                  

                                  Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                                  Q: What's that?
                                  A: It's blue light.
                                  Q: What does it do?
                                  A: It turns blue.

                                  1 Reply Last reply
                                  0
                                  • VRoninV Offline
                                    VRoninV Offline
                                    VRonin
                                    wrote on last edited by VRonin
                                    #21

                                    Replace out<<ui->tableWidget->item(i, j)->text(); with out<<ui->tableWidget->model()->index(i, j).data().tostring(); to prevent segfaults

                                    The problems I highlighted are still present though

                                    @VRonin said in How to save a table in a file:

                                    In your code above you are not:

                                    • Writing any new line to separate rows.
                                    • Writing any column separator
                                    • Escaping column separators inside the data

                                    "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                    ~Napoleon Bonaparte

                                    On a crusade to banish setIndexWidget() from the holy land of Qt

                                    D 1 Reply Last reply
                                    3
                                    • VRoninV VRonin

                                      Replace out<<ui->tableWidget->item(i, j)->text(); with out<<ui->tableWidget->model()->index(i, j).data().tostring(); to prevent segfaults

                                      The problems I highlighted are still present though

                                      @VRonin said in How to save a table in a file:

                                      In your code above you are not:

                                      • Writing any new line to separate rows.
                                      • Writing any column separator
                                      • Escaping column separators inside the data
                                      D Offline
                                      D Offline
                                      Daesos
                                      wrote on last edited by Daesos
                                      #22

                                      @VRonin In a previous version I've added both ";" and "\n", but I forgot to write them again.
                                      However I forgot one case: what happen if I did not create/delete/modify any file, folder, or other?
                                      The cells (i, 2) might be empty and here is where the program fails.
                                      I resolved by editing some code:

                                      void MainWindow::on_pushButton_2_clicked()
                                      {
                                      QFile csv(f_name);
                                      
                                      if(!csv.open(QFile::WriteOnly))
                                          return;
                                      
                                      QTextStream out(&csv);
                                      int tmp_column = 0;
                                      
                                      for(int i = 0; i < ui->tableWidget->rowCount(); ++i){
                                          for (int j = 1; j < ui->tableWidget->columnCount(); ++j){
                                              if(ui->tableWidget->item(i, j) != 0)
                                                  out<<ui->tableWidget->item(i, j)->text();
                                                  out<<";";
                                                  tmp_column = j;
                                          }
                                          if(ui->tableWidget->item(i, tmp_column) != 0)
                                              out<<"\n";
                                      }
                                      
                                      out.flush();
                                      csv.close();
                                      }
                                      

                                      It may not be quite good-looking but it works:

                                      0_1531227135676_6d7d870f-2968-47b7-8941-b6ffbaac0431-image.png

                                      I've also prevented segmentation faults like this for example:

                                      ui->tableWidget->setItem(index_delete, 0, itm);
                                          if(ui->tableWidget->item(index_delete, 2) != 0 && ui->tableWidget->item(index_delete, 2)->text() != "Deleted")
                                              ui->tableWidget->setItem(index_delete, 3, new QTableWidgetItem(QDateTime::currentDateTime().toString()));
                                      
                                      1 Reply Last reply
                                      0
                                      • VRoninV Offline
                                        VRoninV Offline
                                        VRonin
                                        wrote on last edited by VRonin
                                        #23

                                        Try naming a folder Ugly; Name and save your model

                                        "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                                        ~Napoleon Bonaparte

                                        On a crusade to banish setIndexWidget() from the holy land of Qt

                                        D VRoninV 2 Replies Last reply
                                        1
                                        • VRoninV VRonin

                                          Try naming a folder Ugly; Name and save your model

                                          D Offline
                                          D Offline
                                          Daesos
                                          wrote on last edited by
                                          #24

                                          @VRonin You got me, this is another case to write.

                                          1 Reply Last reply
                                          0

                                          • Login

                                          • Login or register to search.
                                          • First post
                                            Last post
                                          0
                                          • Categories
                                          • Recent
                                          • Tags
                                          • Popular
                                          • Users
                                          • Groups
                                          • Search
                                          • Get Qt Extensions
                                          • Unsolved