How to use a QVector with a custom class

[kasysbi]

Hello everybody...i'm triying to use a QVector with a custom class, can please someone explain me that mecanism? i try this QVector<CoupleStride>.... but the compilation return an error looking like this "ASSERT failure in QVector<T>::operator[]: "index out of range"...

[mrjj]

Hi
There is nothing special QVector needs
and can be used anywhere in code.

What it says is that you use a index that is too big.

So you have error in your code.
Some where you do
mylist[INDEX] and index is not
with in legal range.

-compilation return an error

It only happens when you RUN the app, right ?

also:
if you only do
QVector<CoupleStride> mylist;

The list is empty!
you must append some CoupleStride to it.

[kasysbi]

It only happens when you RUN the app, right ?// yes
In fact, i'm triying to return that QVector<CoupleStride> in a function.

[mrjj]

@kasysbi

well the error is from crashing the list using [].
Returning it should not crash it.

can you show the crashing code ?
You can single step with debugger to find it or
look in the call stack after the crash.

[kasysbi]

this appear on the screen
ASSERT failure in QVector<T>::operator[]: "index out of range", file..........
......\Qt\Qt5.2.1\5.2.1\mingw48_32\include/QtCore/qvector.h.line 369
...
end with the code 3

[Taz742]

@kasysbi hi.
can you post your full code?

[mrjj]

as @Taz742 says, we need to see your code
where you use the list.
Also where you append to list and what size you except it to be.

[Taz742]

@kasysbi
Use this:

#include "mainwindow.h"
#include <QApplication>
#include "QLocale"
#include "QDebug"
#include "QJsonArray"
#include "QJsonDocument"
#include "QJsonValue"
#include "QJsonObject"
#include "QTextCodec"

class QtIsMyLife{
    public:
        int Age;
        QString Name;
        QString Familyname;

        QtIsMyLife(int _age, QString _name, QString _familyname) {
            this->Age = _age;
            this->Name = _name;
            this->Familyname = _familyname;
        }
};

QVector<QtIsMyLife*> GetNewVector() {
    QVector<QtIsMyLife*> my_vector;
    my_vector.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    my_vector.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    my_vector.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    my_vector.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));

    return my_vector;
}

void GetNewVector(QVector<QtIsMyLife*> &vec) {
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
    vec.push_back(new QtIsMyLife(21, "Tazo", "Leladze"));
}

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    QVector<QtIsMyLife*> vec = GetNewVector();

    qDebug() << vec.size();

    QVector<QtIsMyLife*> vec_2;

    GetNewVector(vec_2);

    qDebug() << vec_2.size();

    return a.exec();
}

[kasysbi]

@Taz742
that was very helpfull thanks a lot...and it seems like use "data" pointer is better than use the [] operator with the main vector...thanks!