Scope problem maybe?

[Nefastious]

Well, as requested here comes the code:

class mainwindow : public QMainWindow {
...
public:
        //declaring the SqlTable model
        QSqlTableModel *model;
        //declaring the searchBox
        QLineEdit *searchBox;
...
}

class mainwindow : public QMainWindow {
...
public:
        //declaring the SqlTable model
        QSqlTableModel *model;
        //declaring the searchBox
        QLineEdit *searchBox;
...
}

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And later on in the implementation file:

//this submits all changes to the database
void mainwindow::save() {
    model->submitAll();
}

//this submits all changes to the database
void mainwindow::save() {
    model->submitAll();
}

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or even,

/*this funtion sets up everything in the toolbar (buttons, icons, descriptions of buttons, connections)
  and menus*/
void mainwindow::setting_up_toolbar_menus() {
...
     ui->toolBar->addWidget(searchBox);
     searchBox->show();
     QAction *searchAct;
...
}

/*this funtion sets up everything in the toolbar (buttons, icons, descriptions of buttons, connections)
  and menus*/
void mainwindow::setting_up_toolbar_menus() {
...
     ui->toolBar->addWidget(searchBox);
     searchBox->show();
     QAction *searchAct;
...
}

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Hope this helps...