How to add a widget to QMainWindow layout?

Question

I'm using the code below to add a QPushButton to a ui:

    QPushButton *mine[PlayForm->horizontal][PlayForm->vertical];
    for(int i=0; i<PlayForm->horizontal; i++)
    {
        for(int j=0; j<PlayForm->vertical; j++)
        {
            QWidget wdg;
            mine[i][j] = new QPushButton(" ", &wdg);
            mine[i][j]->setGeometry(size*i, size*j, size, size);
            mine[i][j]->show();
            PlayForm->layout()->addWidget(mine[i][j]);
        }
    }

But I get this message:

QMainWindowLayout::addItem: Please use the public QMainWindow API instead

What should I do?

QMainWindowLayout::addItem: Please use the public QMainWindow API instead this is my problem and I don't know what should I do — Khosi, Mar 26 '13 at 11:26

score 8 · Accepted Answer · edited May 23 '17 at 11:54

8

You are creating a temporary parent widget on the stack, and using a reference to it for the QPushButton - this is a fine way to get a segfault.

The parent widget argument defaults to nullptr, which is acceptable for you as the layout takes ownership of it.

//QWidget wdg;
mine[i][j] = new QPushButton( " " );

The error message you are getting is answered by this question. In short it means that you should not modify the QMainWindow layout; you need to a create a widget, add that as the central widget, and then modify the central widget's layout.

edited May 23 '17 at 11:54

Community

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answered Mar 26 '13 at 10:19

cmannett85

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thanks. but I'm not sure I'm understanding correctly. If I use pointer to `QPushButton` and then new that, this is correct? – Khosi Mar 26 '13 at 11:25
I saw that link before ask question, but I didn't get it. Could you explain that? – Khosi Mar 26 '13 at 11:56

How to add a widget to QMainWindow layout?

1 Answers1

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