Question

I tried to use QTableView in a program. I’ve already fixed all bugs I got in the model in another testproject I started.

Now, I tried to insert the model and the QTableView in my mainproject, but in contrast to the other project, the QTableView just opens for half a second and then closes immediately! However, the same code was working well in the testproject.

This is my code in the testproject:

#include <QApplication>
#include <QTableView>
#include "start.h"
#include "mymodel.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QTableView tableView;
    MyModel myModel(0);
    tableView.setModel(&myModel);
    tableView.setSelectionBehavior(QAbstractItemView::SelectRows);
    tableView.show();
    //Start w;
    //w.show();

    return a.exec();
}

And this is the relevant code in the main project:

void Startseite::on_ButtonOK_clicked()
{
    switch (ui->menuLeiste->currentIndex()) {

    case 0:
    {
        QTableView tableview;
        Model myModel(0);
        tableview.setModel(&myModel);
        tableview.setSelectionBehavior(QAbstractItemView::SelectRows);
        tableview.show();
        break;
    }

    case 1:
    {
        // other functions...
    }
}
}

Model is a QAbstractTableModel.

Does anyone knows, why the TableView closes?

Thanks!

Answer 1

You need to create your model and view on the heap, otherwise they will go out of scope at the end of on_ButtonOK_clicked and will be destroyed.

It works in your test project because you create the both in main and they are only destroyed at the end of the program.