Application output "flashes", but my GUI is not displayed on the screen.

Neutrox

I have a problem with my project when a start with qDebug.
In my code I have two .txt files that I need to read in my program. But when I
put All.txt (my txt file) and dbconf.txt (my txt file) in my Working Directory my GUI doesn't show on screen.
When I delete All.txt and dbconf.txt, my GUI show but my application has no purpose because I gotta read and write in these text files.
How can I solve it?

Chris Kawa

It's impossible to help without looking at the code. There can be million number of reasons matching your brief description.

Neutrox

this is just a part of my code, but now to view the file I try to open when starting the program.

@{
ui->setupUi(this);

//Write all paths in the GUI when start the program.
_directorydbconf = "dbconf.txt";


if (!_directorydbconf.isEmpty()) {
        QFile file&#40;_directorydbconf&#41;;
        if (!file.open(QIODevice::ReadOnly)) {
            QMessageBox::critical(this, tr("Error"), tr("Could not open file"));
            return;
                                             }

        QTextStream in(&file);
        line1 = in.readLine();
        line12 = line1.mid(4);
        line2 = in.readLine();
        line21 = line2.mid(4);            //Reads from the fourth character
        ui->lineEdit_4->setText(line21);
        line3 = in.readLine();
        line31 = line3.mid(4);            //Reads from the fourth character
        ui->lineEdit_5->setText(line31);
        line4 = in.readLine();
        line41=line4.mid(4);              //Reads from the fourth character
        ui->lineEdit_6->setText(line41);


                         }
QFile file4(_directorydbconf);
QTextStream in4(&file4);
if(!file4.open(QFile::ReadOnly)){
         qDebug() << "could not open file writing";
                    return;
}else{
for(int x=0; x<7; x++){

    _text11= in4.readLine();

}

}
for(int x=0; x=7; x++){

_text21= in4.readLine();
}

}
@

When I put the dbconf.txt file in the working directory, the GUI does not appear when I remove(dbconf.txt) the GUI file appears but with the mesagem "Could not open file".

DBoosalis

It looks like there might be an error in your code with where you declare QFile. YOu declare it inside some brackets but I think it is going out of scope where you create a datastream and try to read it Try moving QFile to the top of the program

Binary91

Yes, this is definitely an error. I'm wondering why compiler doesn't throw an error while trying to compile that code...

Neutrox

Yes, there are errors.
As I was learning and riding my application for a long time, I made mistakes I did not realize.
I modified only the logic to read the file and opened it to read only once.

Thanks for help! :)