Phonon linking problem

Printable View

Hello, I seem to be having a bit of a problem using phonon as well as QSound::play();

When I try to use QSound::play();, the only sound I get is the windows error beep(ding), so I decided to use Phonon instead, even though I'm fairly certain it's a bit more resource intensive to use two instances of Phonon (one for media play back and one for environment sound effects to replace QSound). However, I am now having problems with Phonon as well.

I followed to example for Phonon included with the Qt SDK, included all that I needed for phonon, and added the QT += phonon to my project file. Still, I am having undefined reference errors when I try to compile. It doesn't seem that Phonon is being linked to my project properly, am I missing something?
Code:

debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:28: undefined reference to `_imp___ZN6Phonon11MediaSourceC1ERK7QString' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:28: undefined reference to `_imp___ZN6Phonon11MediaObject16setCurrentSourceERKNS_11MediaSourceE' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:28: undefined reference to `_imp___ZN6Phonon11MediaSourceD1Ev' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:29: undefined reference to `_imp___ZN6Phonon11MediaObject4playEv' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:28: undefined reference to `_imp___ZN6Phonon11MediaSourceD1Ev' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:34: undefined reference to `_imp___ZN6Phonon11AudioOutputC1ENS_8CategoryEP7QObject' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:35: undefined reference to `_imp___ZN6Phonon11Me***-build-desktop/../***/***.cpp:36: undefined reference to `_imp___ZN6Phonon11MediaObject15setTickIntervalEi' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:37: undefined reference to `_imp___ZN6Phonon10createPathEPNS_9MediaNodeES1_' debug/***.o:D:\Projects\***-build-desktop/../***/***.cpp:37: undefined reference to `_imp___ZN6Phonon4PathD1Ev'

13th August 2010, 06:27
tbscope

Re: Phonon linking problem

Did you compile Qt with Phonon support?
Or, did you install the Qt Phonon library (it might be separate on your system)
13th August 2010, 17:14
Decessus

Re: Phonon linking problem

Yes, I would assume that Phonon is installed because I am able to compile the phonon example, as well as it runs fine. Also, in my lib directory in Qt, I have libphonon.a and libphonond.a
13th August 2010, 17:22
Zlatomir

Re: Phonon linking problem
Do you have this line:
Code:

QT += phonon
in your .pro file?
13th August 2010, 17:24
Decessus

Re: Phonon linking problem

Yes sir I do
13th August 2010, 17:49
Zlatomir

Re: Phonon linking problem

I have tried to replicate that, and i can't

The only case when i get that errors, is missing QT += phonon, did you "rebuild" (run qmake again) after adding the QT += phonon? (sometimes simply clicking on the Build button <the green one> doesn't rebuild and the compiler still doesn't find the libraries, even if added)

Also check that <Phonon/MediaObject> and <Phonon/MediaSource> files are included, not only forward declared.

Re: Phonon linking problem

Well I manually ran qmake, since rebuild did not work, and it is not trying to link the phonon libs

Code:

Running build steps for project ***...
Starting: "c:/qt/2010.04/qt/bin/qmake.exe" D:/Projects/***/***.pro -r -spec win32-g++ 
The process "c:/qt/2010.04/qt/bin/qmake.exe" exited normally.

This is my .pro file

Code:

QT       += core gui \
            phonon
 
TARGET = ***
TEMPLATE = app
 
SOURCES += main.cpp\
        ***.cpp
 
HEADERS  += ***.h
 
FORMS    += ***.ui
 
RESOURCES += \
    images.qrc

13th August 2010, 17:57
tbscope

Re: Phonon linking problem

One thing that might be a problem is the difference in build configurations between the phonon libs and your program.

Is the Qt and Phonon library compiled with the same compiler and settings as your program?
13th August 2010, 18:02
Decessus

Re: Phonon linking problem

I never manually compiled any of the libs, I downloaded the SDK for Windows.
13th August 2010, 18:07
tbscope

Re: Phonon linking problem

Bingo :-)

Which version did you download? Visual studio version or minGW?

After finding out which you downloaded, how do you build your program. Using visual studio? or the minGW tools?

If both differ, you get these errors.
13th August 2010, 18:10
Decessus

Re: Phonon linking problem

I downloaded the minGW version as well as I use the minGW toolchain
13th August 2010, 18:18
tbscope

Re: Phonon linking problem

You downloaded the minGW toolchain separatly? If so, this might also be a problem.

Suggestion:

Remove all
Download the latest Qt SDK. This includes everything and works out of the box.
13th August 2010, 18:23
Decessus

Re: Phonon linking problem

No I did not download it seperately, I use the MinGW toolchain that comes with the SDK
13th August 2010, 18:28
Decessus

Re: Phonon linking problem

Is there a qmake flag that I can manually invoke for libphonon?
13th August 2010, 18:39
tbscope

Re: Phonon linking problem

Quote:

Originally Posted by Decessus

Is there a qmake flag that I can manually invoke for libphonon?

I'm not sure what you mean, but I guess no.
You include the phonon library with QT += phonon

What you see are linker errors which means that the linker can't find certain symbols in the phonon library.
This in turn means that the library isn't found or it is compiled with another compiler (symbols are messed up).

Since neither case describes your problem, I'm out of ideas.
Can you please give more information? Describe exactly what you downloaded, every step you did between installing what you downloaded and building your program, including the full source code.
13th August 2010, 19:08
Decessus

Re: Phonon linking problem

Hmm, well I seemed to have solved my problem, which apparently was caused by manually including windows.h in an attempt to use PlaySound();

Thank you for your patience and help :)