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mixxx package

On Mac,when I run the Mixxx.app ,I get"must construct a QApplication before a QPaintDevice"

Asked by zfp

On Mac,when I run the Mixxx.app ,I get"must construct a QApplication before a QPaintDevice"

Note that when running from source,it is ok. But when run from the installer, it crashed.

warning:[main]:On Mac ,you might be loading two sets of Qt binaries into the same process.
warning:[main]:QObject:: movetoThread: Current thread is not the object's thread.
Cannot move to target thread.

Any help would be greatly appreciated.

Thanks a lot & Best regards.
Sincerely.

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zfp
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zfp (84024482-j) said : 		#1

The messages in console :

Debug:[main]: Displaying Mixxx
Debug:[main]: Running Mixxx
QWidget:Must construct a QApplication before a QPaintDevice
Abort trap

then Mixxx crashed.

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Miha Gašperšič (miha.gaspersic) said : 		#2

Hello Zfp,

It will be probably the best way, that you post your question and official launchpad Mixxx question page. You can find it on this url:
https://answers.launchpad.net/mixxx. They could solve your problem easly.

If this help you some way, please mark it as solved.

Regards,
Miha

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zfp (84024482-j) said : 		#3

In this case when loading certain QT plugins look for them in the system instead of in the .app therefore triggering the load of the Qt installed in your machine. This is why you get the message of two sets of Qt binaries.

Create a blank file "qt.conf" in your "Mixxx.app/Contents/Resources/" directory.
Insert the following 2 lines into "qt.conf" and save.

[Paths]
Plugins = plugins

This file forces qt binaries in the .app to load the plugins contained in the package, and not those installed in your system.
Maybe the file could be included in the Mixxx distribution...

Problem solved

Thanks jus.

This is his solution.