QtWarning QMetaObject::connectSlotsByName: No matching signal for on_something_event()
Search with Google I found a post that explained, very clearly, what happens. I'd bet it's somewhere in thedocumentation of Qt, but so far I have not found anything about that in the event sections I read.
The fact is that the setupUi() function, which is created when you generate a window using Designer or Qt Creator, does a special search on all the functions named on_widgetName_eventName() functions and attempts to connect them. This is neat, although it means that if you have a slot named that way which is not directly related to a widgetName and a valid eventName for that widget, the connect() call fails and you getthat warning at runtime.
You have two solutions here:
1) Rename your functions to not use on_... as the introducer (i.e. you could use slot_... instead, or the Qt naming convention such as onName1Name2()...)
2) Rename your functions so the auto-connect happens as expected!
In the second case, you need to rename the function to match the widget name exactly and then the eventname exactly. For example, if you have a QPushButton named clickHere, you could create a function named:
on_clickHere_clicked()
and that function will be called any time the user clicks your clickHere button (and of course you don't have to do the connect yourselves.)