ReadMultiple Files at one time

[giblit]

First of all, I couldnt figure out how to map or get an array of variable names basically I was trying like QFile file[i] where I would be like 1-3 and i wanted it to be QFile file1, QFile2, QFile3 same with QTextStream because I think if I had that working it would be a lot better.

Secondly with my Code below I can read in two files, but if I try and read in a 3rd I get an application failure and it wont even open the exe get this error message:
ASSERT failure in QLIST<T>:perator[]: "index out of range", file C:\QtSDK\Desktop\Qt\4.8.1\mingw\include/Qtcore/qlist.h, line 477. and two mesages saying Invalid parameter passed to C runtime.

my code is here PS: if i make my two loops i < 2 and comment out the other 3 files it works but I want to read all 5 =/

#include <QtGui>
#include "datelistdialog.h"
#include "abitem.h"
#include <sstream>
#include <iostream>
using namespace std;
DateListDialog::DateListDialog()
{
 
    QStringList foods;
    QStringList dates;
    QStringList totalProteins;
    QStringList totalFats;
    QStringList totalCarbs;
    QStringList labels;
    labels << tr("Date") << tr("Food") << tr("Total Protein") << tr("Total Carb") << tr("Total Fat");
 
    treeWidget = new QTreeWidget;
    treeWidget->setColumnCount(5);
    treeWidget->setHeaderLabels(labels);
 
 
 
    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(treeWidget);
    setLayout(mainLayout);
 
    for(int i = 0; i < 3; i++){
 
        string filename = "/";
        string type [] = {"date","food","totalProtein","totalCarb","totalFat"};
        string number;
        stringstream convert;
        filename.append(type[i]);
        convert << i;
        number = convert.str();
         filename.append(".txt");
 
 
 
         QString filename2 = QString::fromStdString(filename);
       QFile i(QDir::homePath() + filename2);
    if (i.open(QIODevice::ReadOnly)) {
 
         QTextStream input(&i);
        input.setCodec("UTF-8");
        while(!input.atEnd()){
 
                if(filename == "/date.txt"){
                    dates << input.readLine();
                } else if(filename == "/food.txt"){
                    foods << input.readLine();
                }  else if(filename == "/totalProtein.txt"){
                    totalProteins << input.readLine();
                } else if(filename == "/totalCarb.txt"){
                    totalCarbs << in.readLine();
                    in.readLine();
                } else if(filename == "/totalFat.txt"){
                    totalFats << in.readLine();
                    in.readLine();
                }
    }
    }
    }
 
 
 
    for (int i = 0; i < 5; ++i) {
        QTreeWidgetItem* item = new QTreeWidgetItem;
        //item->setText(0,"HELLO");
        item->setText(0, dates[i]);
        item->setText(1, foods[i]);
        item->setText(2, totalProteins[i]);
        item->setText(3, totalCarbs[i]);
        item->setText(4, totalFats[i]);
        treeWidget->addTopLevelItem(item);
 
    }
}

#include <QtGui>
#include "datelistdialog.h"
#include "abitem.h"
#include <sstream>
#include <iostream>
using namespace std;
DateListDialog::DateListDialog()
{

    QStringList foods;
    QStringList dates;
    QStringList totalProteins;
    QStringList totalFats;
    QStringList totalCarbs;
    QStringList labels;
    labels << tr("Date") << tr("Food") << tr("Total Protein") << tr("Total Carb") << tr("Total Fat");

    treeWidget = new QTreeWidget;
    treeWidget->setColumnCount(5);
    treeWidget->setHeaderLabels(labels);



    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addWidget(treeWidget);
    setLayout(mainLayout);

    for(int i = 0; i < 3; i++){

        string filename = "/";
        string type [] = {"date","food","totalProtein","totalCarb","totalFat"};
        string number;
        stringstream convert;
        filename.append(type[i]);
        convert << i;
        number = convert.str();
         filename.append(".txt");



         QString filename2 = QString::fromStdString(filename);
       QFile i(QDir::homePath() + filename2);
    if (i.open(QIODevice::ReadOnly)) {

         QTextStream input(&i);
        input.setCodec("UTF-8");
        while(!input.atEnd()){

                if(filename == "/date.txt"){
                    dates << input.readLine();
                } else if(filename == "/food.txt"){
                    foods << input.readLine();
                }  else if(filename == "/totalProtein.txt"){
                    totalProteins << input.readLine();
                } else if(filename == "/totalCarb.txt"){
                    totalCarbs << in.readLine();
                    in.readLine();
                } else if(filename == "/totalFat.txt"){
                    totalFats << in.readLine();
                    in.readLine();
                }
    }
    }
    }



    for (int i = 0; i < 5; ++i) {
        QTreeWidgetItem* item = new QTreeWidgetItem;
        //item->setText(0,"HELLO");
        item->setText(0, dates[i]);
        item->setText(1, foods[i]);
        item->setText(2, totalProteins[i]);
        item->setText(3, totalCarbs[i]);
        item->setText(4, totalFats[i]);
        treeWidget->addTopLevelItem(item);

    }
}

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[anda_skoa]

my guess is that you get the assert when accessing the QStringLists in line 71 and later. Maybe you should check that they all have 6 entries.

Also: naming the QFile instance with the same name as the loop variable looks very weird.

Btw, the easiest way to create filenames based on a patter is QString::arg(). Basically you create a QString using placeholders and then use arg() calls to replace them with data

const QString filenamePattern( "/%1%2.txt" );
 
QString filename = filenamePattern.arg( type[i] ).arg( i );

const QString filenamePattern( "/%1%2.txt" );

QString filename = filenamePattern.arg( type[i] ).arg( i );

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Cheers,
_

[giblit]

thanks about the arg that will make life much easier, and btw you were correct about the line 71 and later..I did a .size() check on all of them and found that one of my txt files was only one line instead of 4 like it should have been reason for this was when I was writing the file I forgot the output << endl; (well I had it but it was commented out on that one instead of all the others =p) Thanks again.
EDIT: the reading of multiple files was working correctly whole time like you thought.

[ChrisW67]

Line 42 should be generating a warning that QFile i masks the int i loop counter (line 28) also.

[giblit]

I didn't get any errors but I can rename QFile i to QFile file. tbh I was tyring to make it Qfile 1, Qfile 2, ect by using the i but it just made the variable name i and it works having the same variable name for them all.

The program is working perfectly now though btw