Question

I am going crazy with this problem.

I have this self-defined struct

struct oneRectangle
{
    QString partName;
    QGraphicsRectItem * rectangle;
};

And I have a List use this struct as a template:

QList<oneRectangle> partList;

After I append an entity of struct(without init the pointer), I need to do something like this:

partList.at(index).rectangle = some pointer points to a QGraphicsRectItem

But, I got an error saying the struct is a read-only struct. I tried to malloc the pointer first, then append it to the list, But when I assign address to the pointer, I still get the error.
What’s the problem here?

Answer 1

Change

partList.at(index).rectangle

into

partList[index].rectangle

as QList::operator[](int) returns a modifiable reference, where QList::at(int) returns a const reference (and is thus not modifiable).