Trying to construct an instance of an invalid type, type id: 145

[smita30apr]

Hi,

I am getting these messages as warnings in my Desktop Application using Qt 5:

Trying to construct an instance of an invalid type, type id: 145
Trying to construct an instance of an invalid type, type id: 145
Trying to construct an instance of an invalid type, type id: 145
Trying to construct an instance of an invalid type, type id: 145

The gui runs fine. Its just that I get these warnings. What could be wrong?

Thanks :)

[leon.anavi]

Could you please provide the source code which generates this warning? I guess that you might be using QVariant in an appropriate way.

[smita30apr]

Thank you for your reply!

QVariant is being used in many places in the code actually. So What do you mean by using QVariant unappropriately? I can search for all existing QVariants, but how to see if its used correctly. Do you have any idea about the significance of "145" id, that its generating.

[SGaist]

Hi,

Did you:

• declared your type with Q_DECLARE_METATYPE ?
• call qRegisterMetaTypeStreamOperators and implement both stream operators ?

[smita30apr]

Yes I have. Declared my new type with Q_DECLARE_METATYPE and used qRegisterMetaTypeStreamOperators

[smita30apr]

I tried to debug, seems its happening with a QTreeView. My code is below

@
QAction *show_user_action = QAction("User");
show_user_action->setCheckable(true);
show_user_action->setChecked(show_user); connect(show_user_action,SIGNAL(triggered(bool)),
m_directory_view,SLOT(show_column(bool)));
@

On Calling:
show_user_action->trigger();
those warnings are displayed.

the slot code is:

@
show_column(bool show) {

QAction *action = qobject_cast< QAction *>(QObject::sender());
QString action_name = action->get_name();
m_filter_model->set_column_visible(action_name,show);
m_directory_view->header()->resizeSections(QHeaderView::ResizeToContents);
}
@

The last line m_directory_view->header()->resizeSections(QHeaderView::ResizeToContents); generates the warning.

Any clue here?

[edit: added missing coding tags @ SGaist]

[SGaist]

Well… It looks unrelated.

Do you have any QVariant stuff in your code ? QSettings ?

[smita30apr]

Well, I added a breakpoint at m_directory_view->header()->resizeSections(QHeaderView::ResizeToContents);
and once it is executed it generates that warning. Its strange though.
But I use both QVariant and QSettings. Actually line 3 at the above code:
show_user_action->setChecked(show_user); <- show_user is a QVariant stored in QSettings.

What can I check for here?

[SGaist]

Are you storing one of your custom class in QSettings ?