Phonon

[Alexander Neundorf]

On Tuesday 31 May 2011, Harald Sitter wrote:
> On Tue, May 31, 2011 at 7:58 PM, Michael Jansen <kde at michael-jansen.biz> 
wrote:
> > On Tuesday 31 May 2011 19:34:57 Harald Sitter wrote:
> >> On Tue, May 31, 2011 at 12:31 AM, Alexander Neundorf <neundorf at kde.org>
> > 
> > wrote:
> >> > On Sunday 22 May 2011, Alexander Neundorf wrote:
> >> > ...
> >> > 
> >> >> > > There will be a PhononConfig.cmake file, which will be found
> >> >> > > by
> >> >> > > find_package(), and it will contain all the information about
> >> >> > > the
> >> >> > > installed phonon, like e.g. the include dir.
> >> >> > > It will be placed in lib/cmake/phonon/.
> >> >> > > Alternatively it could also go into lib/phonon/cmake/.
> >> >> > 
> >> >> > lib/cmake/phonon sounds best (to have everything in a central
> >> >> > place :)).
> >> >> 
> >> >> Ok.
> >> > 
> >> > One more thing: phonon installs some things by default outside
> >> > CMAKE_INSTALL_PREFIX.
> >> > This is the Qt plugin and the Qt prj file.
> >> > 
> >> > This is not good. By default nothing should be installed outside
> >> > CMAKE_INSTALL_PREFIX, because the one who installs may not have write
> >> > permissions there and he may have chosen the install prefix so that it
> >> > doesn't touch the rest of the system.
> >> 
> >> I agree.
> >> 
> >> > So, I'd like to change this so that the default is inside
> >> > CMAKE_INSTALL_PREFIX, maybe with a message that some things may have
> >> > to be set up, and that it can optionally be changed to whatever is
> >> > wanted.
> >> 
> >> If we'd install the Qt plugins anywhere but in the designated Qt
> >> directories, Qt would not find them, making for a major inconvenience
> >> for the user. I am not quite sure how to install to C_I_P and maintain
> >> sane default behavior. If I wanted to develop an application using
> >> Phonon and Qt Designer (though QML will have the very same problem
> >> really), I surely would not want to jump through all sorts of hoops to
> >> get the install paths right.
> >> 
> >> So, no idea what to do, but simply installing to C_I_P will not do as
> >> it moots the users/developers experience.
> > 
> > By default install into the CMAKE Prefix.
> > 
> > Add a option to install that file into the qt prefix. I have to emphasize
> > that the default of that option has to be "install into the cmake
> > prefix". Those qt-streamer guys  failed to get that right.
> > 
> > If that option not set print out a message stating it will not work and
> > if they want to have it work they have to use that option but that will
> > probably require root right for installation.
> > 
> > With qt 4.8 print out a warning if that option is not set and inform the
> > user that he has to set QMAKESPEC correctly if cmake prefix != qt prefix
> > and the option is not set and the sermon above.
> 
> I have no idea what that is supposed to mean.

I think it means this:

default to inside CMAKE_INSTALL_PREFIX

if QT_PREFIX != CMAKE_INSTALL_PREFIX
  print "Change Set PLUGIN_INSTALL_DIR to $QT_PLUGIN_DIR to make it work"
  if QT_VERSION >= 4.8
    print "You can also adjust the env.var QMAKESPEC


> At any rate cmake prefix != qt prefix is absolutely and entirely
> insufficient as distributions could be putting their Qt plunder

With Qt 4.8 the env.var QMAKESPEC is honored (am I right with this ?), so this 
has to be adjusted, similar to other env.vars like e.g. PKGCONFIG_PATH.

With versions < 4.8, it will not work (am I right with this ?), but at least 
developers and packagers will be able to compile everything without getting 
something into their system directories.
Who needs it to work, should follow the advice which should be printed. 
Maybe this can be handled by the build scripts ?

Alex