Patch for better Qt4 support

[Andreas Pakulat]

Hi,

here it is, my first try to provide better (as in: more easy to use) Qt4
support for KDevelop 3.4. The attached patch compiles fine here and I
also made sure that with a qmake project everything works as before.

The changes that I've done are:

- provide a new tab on the C++ configuration for Qt options
- move the include-style option to the new tab
- provide configuration options for qt version, qt directory and
  designer integration on the new tab page
- remove the designer integration configuration from kdevelop's settings
  page
- use the already existing qt root entry in the project dom to create
  path's for designer and qmake (in partcontroller.cpp and
  trollprojectpart.cpp)
- make the configured qt directory "override" the QTDIR environment
  variable in trollprojectpart.cpp, but keep the precedence of a
  specifically configured environment variable QTDIR
- change the logic of qt version and include style, so that the include
  style can be choosen freely for qt4 (but only qt3 style is available
  for qt3). I think this makes more sense, because people out there also
  use qt3 style with Qt4 projects.

That's all so far, I tried to provide proper what's This entries for the
new options (copying existing ones, if available) and I also found a
small bug during this: The what's this entries of other radio buttons on
the C++ configuration tab's are the same as for the Qt styles, so I
think these should be changed (will file a bugreport just after
finishing the mail).

Also I thought a bit more about stuff that could be improved, depending
on wether it is halfway as easy as the above changes I'll try to come up
with patches for the following (withing the next few weeks):

- Check for validity of the Qt directory given in the C++ configuration
  page
- Check the existing qmake templates to make sure that they configure
  the Qt options correctly, eventually asking for a Qt directory upon
  creation (not sure wether the "wizard" supports this).
- Improve qmake4 support, IIRC the qmake manager didn't get along very
  well with a Qt4 project I had, I'll try to at least make him recognize
  the various new variables
- improve the subclassing right-click menu and class wizard to provide
  correct subclassing for Qt4 .ui files (for now I'll start with the
  multiple inheritance method)

Any comments are welcome (for the patch and the planned items),
especially to tell me that I shouldn't try as you can't make such large
changes in kdevelop3.4 so late. (I'm sorry I didn't try earlier, I
always thought it would be much harder to implement...).

Andreas

-- 
Never give an inch!