Help with QTreeView

[arturio955]

Can somebody please help. I have a problem opening the department tab in 1st company after adding employee in department, its crashing. It gives sigsegv signal.

CompanyModel::CompanyModel(QObject *parent)
    : QAbstractItemModel(parent){}

QModelIndex CompanyModel::index(int row, int column, const QModelIndex &parent) const {
    if (!hasIndex(row, column, parent))
        return QModelIndex();

    if (!parent.isValid()) {
        return createIndex(row, column, quintptr(-1));
    } else if (parent.internalId() == quintptr(-1)) {
        return createIndex(row, column, parent.row());
    } else {
        return createIndex(row, column, parent.internalId() * 1000 + parent.row());
    }
}

QModelIndex CompanyModel::parent(const QModelIndex &index) const {
    if (!index.isValid())
        return QModelIndex();

    quintptr internalId = index.internalId();
    if (internalId == quintptr(-1))
        return QModelIndex();

    if (internalId < 1000) {
        return createIndex(internalId, 0, quintptr(-1));
    } else {
        int companyIndex = internalId / 1000;
        int departmentIndex = internalId % 1000;
        return createIndex(departmentIndex, 0, companyIndex);
    }
}

int CompanyModel::rowCount(const QModelIndex &parent) const {
    if (!parent.isValid())
        return companies.size();

    if (parent.internalId() == -1) {
        return companies.at(parent.row()).departments.size();
    } else if (parent.internalId() >= 0 && parent.internalId() < companies.size()) {
        return companies.at(parent.internalId()).departments.at(parent.row()).employees.size();
    }

    return 0;
}
int CompanyModel::columnCount(const QModelIndex &parent) const {
    Q_UNUSED(parent);
    return 4;
}

QVariant CompanyModel::data(const QModelIndex &index, int role) const {
    if (!index.isValid())
        return QVariant();

    if (index.internalId() == quintptr(-1)) {
        const Company &company = companies.at(index.row());
        if (role == Qt::DisplayRole && index.column() == 0)
            return company.name;
        else if (role == Qt::DecorationRole && index.column() == 0)
            return company.logo.isNull() ? StaticIcons::companyIcon() : company.logo;
    } else if (index.internalId() < companies.size()) {
        const Department &department = companies.at(index.internalId()).departments.at(index.row());
        if (role == Qt::DisplayRole && index.column() == 0)
            return department.name;
        else if (role == Qt::DecorationRole && index.column() == 0)
            return StaticIcons::departmentIcon();
    } else {
        int companyIndex = index.internalId() / 1000;
        int departmentIndex = index.internalId() % 1000;
        const Employee &employee = companies.at(companyIndex).departments.at(departmentIndex).employees.at(index.row());
        if (role == Qt::DisplayRole) {
            switch (index.column()) {
            case 0: return employee.name;
            case 1: return employee.position;
            case 2: return employee.gender == Gender::Male ? "Мужской" : "Женский";
            }
        } else if (role == Qt::DecorationRole && index.column() == 0) {
            return employee.photo.isNull() ? StaticIcons::employeeIcon() : employee.photo;
        }
    }
    return QVariant();
}

QVariant CompanyModel::headerData(int section, Qt::Orientation orientation, int role) const {
    if (role == Qt::DisplayRole && orientation == Qt::Horizontal) {
        switch (section) {
        case 0:
            return QString("Name");
        case 1:
            return QString("Position");
        case 2:
            return QString("Gender");
        }
    }
    return QVariant();
}

bool CompanyModel::setData(const QModelIndex &index, const QVariant &value, int role) {
    if (!index.isValid() || role != Qt::EditRole) {
        return false;
    }

    if (index.internalId() == quintptr(-1)) {
        Company &company = companies[index.row()];
        if (index.column() == 0) {
            company.name = value.toString();
            emit dataChanged(index, index);
            return true;
        }
    } else if (index.internalId() < companies.size()) {
        Company &company = companies[index.internalId()];
        Department &department = company.departments[index.row()];
        if (index.column() == 0) {
            department.name = value.toString();
            emit dataChanged(index, index);
            return true;
        }
    } else {
        int companyIndex = index.internalId() / 1000;
        int departmentIndex = index.internalId() % 1000;
        Company &company = companies[companyIndex];
        Department &department = company.departments[departmentIndex];
        Employee &employee = department.employees[index.row()];

        switch (index.column()) {
        case 0:
            employee.name = value.toString();
            break;
        case 1:
            employee.position = value.toString();
            break;
        case 2:
            employee.gender = value.value<Gender>();
            break;
        default:
            return false;
        }

        emit dataChanged(index, index);
        return true;
    }

    return false;
}

Qt::ItemFlags CompanyModel::flags(const QModelIndex &index) const {
    if (!index.isValid()) {
        return Qt::NoItemFlags;
    }
    Qt::ItemFlags flags = Qt::ItemIsSelectable | Qt::ItemIsEnabled;
    if (index.column() >= 0 && index.column() <= 3) {
        flags |= Qt::ItemIsEditable;
    }
    return flags;
}

[JonB]

@arturio955
Hi. If you think about it, nobody can possibly help you with your issue from the description you give without any code, can they? [Ah, now you have added some code. I would suggest you drastically reduce this code to whatever minimal reproduces the issue, it cannot need all that code, most of it must be irrelevant.]

If you have a SIGSEGV you must run your code from the debugger. When it receives that signal it will break at that point; look in the debugger's stack trace pane to follow it back to the line in your code which caused it and examine that.

After that, Qt provides a QAbstractItemModelTester Class for you to use:

The QAbstractItemModelTester class is a utility class to test item models.

[arturio955]

This post is deleted!

[arturio955]

What can it be if my function in infinity loop

int CompanyModel::rowCount(const QModelIndex &parent) const {
    if (!parent.isValid()) {
        qDebug() << "Root level: Number of companies =" << companies.size();
        return companies.size();
    }

    quintptr id = parent.internalId();

    if (id == quintptr(-1)) {
        if (parent.row() >= 0 && parent.row() < companies.size()) {
            int numDepartments = companies.at(parent.row()).departments.size();
            qDebug() << "Company level: Number of departments in company" << parent.row() << "=" << numDepartments;
            return numDepartments;
        } else {
            qDebug() << "Invalid company index:" << parent.row();
        }
    } else if (id >= 0) {
 
        int companyIndex = id / 1000;
        int departmentIndex = id % 1000;

 
        if (companyIndex >= 0 && companyIndex < companies.size()) {
            const Company &company = companies.at(companyIndex);
            if (departmentIndex >= 0 && departmentIndex < company.departments.size()) {
                int numEmployees = company.departments.at(departmentIndex).employees.size();
                qDebug() << "Department level: Number of employees in department" << departmentIndex << "of company" << companyIndex << "=" << numEmployees;
                return numEmployees;
            } else {
                qDebug() << "Invalid department index:" << departmentIndex;
            }
        } else {
            qDebug() << "Invalid company index:" << companyIndex;
        }
    }

    return 0;
}

output:Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1
Department level: Number of employees in department 0 of company 0 = 1 and than crash

[JonB]

@arturio955 What about stepping through your code in debugger to see what is happening?

[arturio955]

@JonB
1 QList<Company>::data qlist.h 418 0x7ff6151c5413
2 QList<Company>::at qlist.h 434 0x7ff6151c53df
3 CompanyModel::rowCount CompanyModel.cpp 61 0x7ff6151b51d8
5 CompanyModel::index CompanyModel.cpp 11 0x7ff6151b4d4a

[JonB]

@arturio955
That is not " stepping through your code in debugger to see what is happening". I'll leave it to someone else who wants to help you.

[arturio955]

@JonB What did you want?

[JonB]

@arturio955
I am suggesting some sort of debugging effort from you. For example, I originally suggested you allow it to SEGV, then move up the stack trace to which line of code was the last to execute and examine it. You have the source code. If you make me guess

5 CompanyModel::index CompanyModel.cpp 11 0x7ff6151b4d4a

Does that perchance indicate line #11 of CompanyModel.cpp? You will have the line in front of you, so you know. Is that the 11th line of what you show, which seems to be:

int numDepartments = companies.at(parent.row()).departments.size();

? I don't know. If it is, what is the value of companies.at(parent.row()).departments? If it is a different line, what is going on in that line which could cause a SEGV? That sort of thing.

I also linked to the QAbstractItemModelTester Class which might (or might not) reveal more information to you.

Nobody can actually reproduce your issue because they don't know what data you have.

[arturio955]

@JonB
3 CompanyModel::rowCount CompanyModel.cpp 61 0x7ff6151b51d8:
else if (parent.internalId() >= 0 && parent.internalId() < companies.size()) {
return companies.at(parent.internalId()).departments.at(parent.row()).employees.size();
5 CompanyModel::index CompanyModel.cpp 11 0x7ff6151b4d4a:
if (!hasIndex(row, column, parent))
return QModelIndex();