Crash on QString assignment

[Radek]

IMO, the problem isn't in Q_OBJECT (as long as AutochargeData does not use "Qt extras" - it is not an UI object, it declares no properties, slots or signals, etc.) The setOrderID() method is innocent. IMO, the problem is somewhere in the database. For starters, I recommend splitting the setOrderID() statement and seeing whether you pass and what values will the debugger show. Therefore:

QVariant val = query.value("increment_id");   // does it pass?
QString  str = val.toString();                // does it pass? What is in str?
 
setOrderID(str);                              // does it pass? What happens?

QVariant val = query.value("increment_id");   // does it pass?
QString  str = val.toString();                // does it pass? What is in str?

setOrderID(str);                              // does it pass? What happens?

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Pleas, post your findings.

[ce_nort]

I got this figured out shortly before you posted. As predicted, it was something obvious that I was missing. I had created an instance of AutochargeData in the Mainwindow class, but was trying to use it in a different class without creating another instance of it. So it was invalid, as was guessed by the other posts in this thread. Thanks everyone!