[SOLVED] Reload contents of QTableView from textfile

[amban]

Hi Friends,
I have a QTableView which is generated by reading a text file line-by-line. This text file is changing pretty often. I have a refresh button with which i want to reload the table i.e. again read the textfile and generate the table.....
I followed previous discussions and added this :

@QTimer *mytimer = new QTimer(this);

//code to read a txt file line by line and generating a QTableView

connect(mytimer, SIGNAL(timeout()),
         this, SLOT(update()) );
         guitimer->start(1000);

@
But this is not working. Pls suggest how to correct this ?

Thanks

[giesbert]

you are triggering the wrong timer...

[amban]

I made an error in posting ....
@QTimer *mytimer = new QTimer(this);

//code to read a txt file line by line and generating a QTableView

connect(mytimer, SIGNAL(timeout()),
         this, SLOT(update()) );
         mytimer->start(1000);

@

But it doesnt work.....

[giesbert]

It is a bit less code to say what's wrong.

what is this?

has this a sot called update?

do you get some debugger messages?

[amban]

This is the code
@
PendingTab::PendingTab(QWidget *parent)
:QWidget(parent)
{

QTimer *guitimer = new QTimer(this);
QVBoxLayout *mainLayout = new QVBoxLayout;

refreshbutton = new QPushButton(tr("Refresh"));
findbutton = new QPushButton(tr("Find"));
findstring = new QLineEdit;

QHBoxLayout *findLayout = new QHBoxLayout;
findLayout->addWidget(findstring);
findLayout->addWidget(findbutton);

mytable = new QTableView();
mytablemodel = new QStandardItemModel();
mytablemodel->setRowCount(0);

int Max_num_of_Columns(10);
int Max_Number_of_Lines(0);
mytablemodel->setColumnCount(Max_num_of_Columns);

QStringList header_list ;
header_list << ......
mytablemodel->setHorizontalHeaderLabels(header_list);

QProcess *proc = new QProcess();

QFile file&#40;"/path/to/a/text/file"&#41;;
if (!file.open(QIODevice::ReadWrite | QIODevice::Text))
     qDebug() << "Error opening file";

proc->setStandardOutputFile&#40;"/path/"&#41;;
proc->start("/path/to/the/script/file");
proc->waitForFinished();

QTextStream InputDataFile&#40;&file&#41;;
while (!InputDataFile.atEnd())
{

    QString line = InputDataFile.readLine();

    line = line.trimmed();
    QStringList fields = line.split(QRegExp("\\s+"));

    if (fields.size() == Max_num_of_Columns)
    {
        for (int column=0; column< Max_num_of_Columns; column++)
        {
            QStandardItem *item = new QStandardItem(fields[column]);
            mytablemodel->setItem(Max_Number_of_Lines, column, item);

        }
        Max_Number_of_Lines++ ;
    }

}

mytable->setModel(mytablemodel);
mytable->setAlternatingRowColors(true);
mainLayout->addWidget(mytable);
mainLayout->addWidget(refreshbutton);
mainLayout->addLayout(findLayout);
setLayout(mainLayout);

file.close();

connect(guitimer, SIGNAL(timeout()),
         this, SLOT(update()) );
         guitimer->start(1000);

connect(refreshbutton, SIGNAL(clicked()),
          this, SLOT(update()));

connect(findbutton, SIGNAL(clicked()),
        this, SLOT(findButtonClicked()));

connect(findstring, SIGNAL(textChanged(QString)), // For changing the background of the searched key
        this, SLOT(clearColoredRows()));

mytable->setSortingEnabled(true);

}
@

I am using the default update() slot which autopopulated for slots related to "this" i.e. my widget

[tobias.hunger]

Maybe a "QFileSystemWatcher":http://doc.trolltech.com/4.7/qfilesystemwatcher.html would be better than doing timer-based polling of the file?

[wongk]

Update causes the widget to repaint, which has nothing to do with the data in your model. Where are you updating the data in your model?

[amban]

Thanks all for your help. I was unaware that repainting widget doesnt do anything to the data model. So i created a new slot loadTable() and moved the loading table data to the slot. So now i do

@connect(guitimer, SIGNAL(timeout()), this, SLOT(loadTable())); @

Thanks a lot. It works fine.