Finding an specific item in QTreeWidget by its text

[ChrisW67]

This:

#include <QtGui>
#include <QDebug>
 
 
int main(int argc, char *argv[])c++ singelton
{
    QApplication app(argc, argv);
 
    QTreeWidget tree;
    tree.setColumnCount(3);
 
    QFile data("test.txt");
    if (data.open(QIODevice::ReadOnly)) {
        QTextStream s(&data);
        while (!s.atEnd()) {
            QString leituraall = s.readLine();
            QString vr_data = leituraall.section('\t',0,0);
            QString vr_semana = leituraall.section('\t',1,1);
            QString vr_hora = leituraall.section('\t',2,2);
            QString vr_smalldescription = leituraall.section('\t',3,3);
 
            // Look for the date in column zero
            QTreeWidgetItem *group;
            QList<QTreeWidgetItem*> items = tree.findItems(vr_data, Qt::MatchExactly, 0);
            if (items.count() == 0) {   // not found, create new entry
                group = new QTreeWidgetItem(&tree);
                group->setText(0, vr_data);
            }
            else
                group = items.at(0);
 
           // create the child entry 
           QTreeWidgetItem *child = new QTreeWidgetItem(group);
           child->setText(0, vr_semana);
           child->setText(1, vr_hora);
           child->setText(2, vr_smalldescription);
        }
    }
 
    tree.show();
 
    return app.exec();
}

#include <QtGui>
#include <QDebug>


int main(int argc, char *argv[])c++ singelton
{
    QApplication app(argc, argv);

    QTreeWidget tree;
    tree.setColumnCount(3);

    QFile data("test.txt");
    if (data.open(QIODevice::ReadOnly)) {
        QTextStream s(&data);
        while (!s.atEnd()) {
            QString leituraall = s.readLine();
            QString vr_data = leituraall.section('\t',0,0);
            QString vr_semana = leituraall.section('\t',1,1);
            QString vr_hora = leituraall.section('\t',2,2);
            QString vr_smalldescription = leituraall.section('\t',3,3);

            // Look for the date in column zero
            QTreeWidgetItem *group;
            QList<QTreeWidgetItem*> items = tree.findItems(vr_data, Qt::MatchExactly, 0);
            if (items.count() == 0) {   // not found, create new entry
                group = new QTreeWidgetItem(&tree);
                group->setText(0, vr_data);
            }
            else
                group = items.at(0);

           // create the child entry 
           QTreeWidgetItem *child = new QTreeWidgetItem(group);
           child->setText(0, vr_semana);
           child->setText(1, vr_hora);
           child->setText(2, vr_smalldescription);
        }
    }

    tree.show();

    return app.exec();
}

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I have dispensed with the separate QStringList of dates already seen, the code that creates the child is not repeated, no goto. Or even this:

#include <QtGui>
#include <QDebug>
 
 
int main(int argc, char *argv[])                                                                      
{
    QApplication app(argc, argv);
 
 
    QTreeWidget tree;
    tree.setColumnCount(3);
 
    QFile data("test.txt");
    if (data.open(QIODevice::ReadOnly)) {
        QTextStream s(&data);
        while (!s.atEnd()) {
            QStringList fields = s.readLine().split('\t');
 
            // Look for the date in column zero
            QTreeWidgetItem *group;
            QList<QTreeWidgetItem*> items = tree.findItems(fields.at(0), Qt::MatchExactly, 0);
            if (items.count() == 0) {   // not found, create new entry
                group = new QTreeWidgetItem(&tree, fields.mid(0,1));
            }
            else
                group = items.at(0);
 
           // create the child entry 
           QTreeWidgetItem *child = new QTreeWidgetItem(group, fields.mid(1));
        }
    }
 
    tree.show();
 
    return app.exec();
}

#include <QtGui>
#include <QDebug>


int main(int argc, char *argv[])                                                                      
{
    QApplication app(argc, argv);


    QTreeWidget tree;
    tree.setColumnCount(3);

    QFile data("test.txt");
    if (data.open(QIODevice::ReadOnly)) {
        QTextStream s(&data);
        while (!s.atEnd()) {
            QStringList fields = s.readLine().split('\t');
            
            // Look for the date in column zero
            QTreeWidgetItem *group;
            QList<QTreeWidgetItem*> items = tree.findItems(fields.at(0), Qt::MatchExactly, 0);
            if (items.count() == 0) {   // not found, create new entry
                group = new QTreeWidgetItem(&tree, fields.mid(0,1));
            }
            else
                group = items.at(0);
            
           // create the child entry 
           QTreeWidgetItem *child = new QTreeWidgetItem(group, fields.mid(1));
        }
    }

    tree.show();

    return app.exec();
}

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which dispenses with intermediate variables.

If the second column in the data file contains any values that are identical to values in the first column this will fail.

"goto" is not inherently evil. However, using "goto" in code has a long track record of producing unmaintainable spaghetti code because it allows the execution path to jump around arbitrarily (bowl of spaghetti). Using "goto" when there is a perfectly good, well defined alternative (while loop, break, continue, return) is not likely to win many friends.

[Momergil]

This:

[...]

which dispenses with intermediate variables.

If the second column in the data file contains any values that are identical to values in the first column this will fail.

"goto" is not inherently evil. However, using "goto" in code has a long track record of producing unmaintainable spaghetti code because it allows the execution path to jump around arbitrarily (bowl of spaghetti). Using "goto" when there is a perfectly good, well defined alternative (while loop, break, continue, return) is not likely to win many friends.

ChrisW67,

thanks a lot for taking your time to write those two codes. I will test them soon after I do some changes in the code.

Also thanks for the explanation about the use of goto. In case you have time, could you please help me with another "goto situation" in this post? --> http://www.qtcentre.org/threads/4452...etter?p=202750

Thanks!


Momergil