[Qt-interest] Using a single MySQL Connection in the whole project

[David Villalobos Cambronero]

Hi all,

My name is David, I'm really new in Qt.

I'm writing an application to learn it, but I have found a problem
while trying to connect to MySQL.

Here is the scenario:

I have a MDI Widget where I'll add some classes with information, i.e
a widget showing the MySQL server status an other to show the MySQL
Variables.

I can connect successfully to MySQL with the following statement:

QSqlDatabase mainServerConnection = QsqlDatabase::addDatabase("QMYSQL");

In addition I have a class that shows a form for collecting the
connection parameters.

But, How can I use the mainServerConnection in other classes, I have
tried to make it public, but the addDatabase seems not to work. Here
is what I tried:

In MainClass.h
public:
  QSqlDatabase *mainServerConnection;

In MainClass.cpp
mainServerConnection = new QSqlDatabase;
mainServerConnection->addDatabase("QMYSQL");

How can I use a just one MySQL Connection in my whole project?

And many thanks for the help.

PD: BTW I'm not American, so my English is bad, please be patient.

Best regards
David