Hi,

When I started using Qwt I used it in a single class (my only class), but getting bigger and bigger I decided to split it.
So now I have a class handling the mainWindow and another one using only Qwt for plotting curves.

In order to have access to my UI, I used a singleton technique (with getInstance() and static member) with methods in my mainwindow class (like getters or setters to use the ui pointer).

But with that, I have an error when it compile : "QWidget: Must construct a QApplication before a QPaintDevice". With Google I learned it was caused by my static instance of mainwindow.

How can I reconcile a nice way to access my Ui in other classes and Qwt ?

Thanks in advance
Have a nice day