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Read textfile and display on QLabel [SOLVED]

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c++textfilereadlinux
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  • M Offline
    M Offline
    marlenet15
    wrote on 28 Sept 2015, 16:31 last edited by marlenet15
    #1

    So I am trying to read a textfile and display it on a QLabel. This is what I have:

    QFile file("test.txt");
    QLabel *testLabel= new QLabel;
    
    QString line;
    if (file.open(QIODevice::ReadOnly | QIODevice::Text)){
        QTextStream stream(&file);
        while (!stream.atEnd()){
            line = stream.readLine();
            testLabel->setText(line+"\n");
        }
    }
    file.close();
    

    However, it only writes the last line of the file. So if my file is:

    apple
    oranges
    banana

    it only displays banana.

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    • P Offline
      P Offline
      Paul H.
      wrote on 28 Sept 2015, 18:04 last edited by Paul H.
      #2

      It looks to me like your problem is in the loop. You are setting line at each iteration thru the loop to be equal to the line read. You need to append the lines you are reading from the file to line, then set the label after the loop.

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      • M Offline
        M Offline
        marlenet15
        wrote on 28 Sept 2015, 18:42 last edited by
        #3

        Thank you!! I changed it to the following and it works!!!!

        QFile file("test.txt");
        QLabel *testLabel= new QLabel;
        
        QString line;
        if (file.open(QIODevice::ReadOnly | QIODevice::Text)){
            QTextStream stream(&file);
            while (!stream.atEnd()){
        
                line.append(stream.readLine()+"\n");
            }
            testLabel->setText(line);
        }
        file.close();
        
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        0

        3/3

        28 Sept 2015, 18:42

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