comboBox->additem() crash application..

mrjj

Hi
Super.
Try
QString test=cl.value(0).toString();
and see if it crash on that line instead.
else it must mean
ui->comboBox_Cliente is not valid pointer.

VRonin

I know this does not address your problem but it should solve it anyway. Replace all your code with:

QSqlQueryModel* queryModel = new QSqlQueryModel(this);
queryModel.setQuery(QStringLiteral("Select RAGSOC from CLIENTI order by RAGSOC ASC"));
if(dynamic_cast<QSqlQueryModel*>(ui->comboBox_Cliente->model()))
ui->comboBox_Cliente->model()->deleteLater();
ui->comboBox_Cliente->setModel(queryModel);

TheCipo76

@mrjj i've tried and crash on additem()..

comboBox is not a pointer .. i've create it with designer in the ui

TheCipo76

@VRonin it will crash however

Cobra91151

@TheCipo76

Hi! Actually in designer it creates pointers, ui-> is the namespace, and comboBox_Cliente-> is a C++ pointer. What is the error message when it crashes?

TheCipo76

@Cobra91151

in application output :

18:45:34: The process was ended forcefully.
18:45:34: /Users/matteo/Desktop/C++/QT/EasyGest/build-EasyGest-Desktop_Qt_5_11_2_clang_64bit18-Release/EasyGest.app/Contents/MacOS/EasyGest crashed.

VRonin

in the constructor of your class, can you add QObject::connect(ui->comboBox_Cliente,&Qobject::destroyed,[]()->void{qDebug("Something exploded");});?

If you see the output it means you are deleting your ui before reusing it

TheCipo76

@VRonin said in comboBox->additem() crash application..:

QObject::connect(ui->comboBox_Cliente,&Qobject::destroyed,->void{qDebug("Something exploded");});

i don't understand where i have to put it..

in the .h file

after Q_OBJECT ??

VRonin

@VRonin said in comboBox->additem() crash application..:

in the constructor of your class

TheCipo76

@VRonin ok..

no output were showed

i've put it after

ui->setupUi(this);

in the dialog

VRonin

And it still crashes? did you set Qt::WA_DeleteOnClose?

TheCipo76

@VRonin No, i don't know what is it.. sorry but i'm new user of Qt

VRonin

One more try, add QObject::connect(this,&QObject::destroyed,[]()->void{qDebug("Something big exploded");}); and see if you have any output when you crash the application

TheCipo76

@VRonin said in comboBox->additem() crash application..:

QObject::connect(this,&QObject::destroyed,->void{qDebug("Something big exploded");});

no, i don't see any output..

VRonin

This is turning into a mistery now. Can you post the stack trace at the moment of crash?

Cobra91151

@TheCipo76

This crash happens after you addItem() to the ui->comboBox_Cliente?

Try to change the code to:

if (cl.exec()) {
    msg.setText("QUI");
    msg.exec();

    if (cl.first()) {
         msg.setText("OK");
         msg.exec();
    }

    do {
        ui->comboBox_Cliente->addItem(cl.value(0).toString());
    } while (cl.next());
 }

and check if it still crashes?

JonB

@TheCipo76

after first record of database additem() crashes the application

Has nobody yet asked you to run this in a debugger (e.g. from Qt Creator)? And give us the stacktrace? EDIT: Oh, @VRonin has 2 posts above. Please do so!

TheCipo76

@VRonin you mean the os x crash report??

VRonin

@TheCipo76 said in comboBox->additem() crash application..:

you mean the os x crash report??

Nope, the stack trace which is a log of all the functions called up to the point of crash. If you use Qt Creator, see http://doc.qt.io/qtcreator/creator-debug-mode.html#viewing-call-stack-trace

JonB

@TheCipo76
Do you sit inside Qt Creator and run your app from within there via the debugger? We are expecting that when something "crashes", the debugger will catch that and show a stacktrace of exactly where it was in your code.