CMake doesn't know where is Qt4 qmake

Question

I am using Debian OS and I\'m trying to point to cmake where is my Qt4.

I try to build qjson library and with its CMakeLists.txt: http://pastebin.com/fKNp0Qgy

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Answer 1

1) Where is your qtchooser configuration file?

  $: locate qtchooser | grep conf

2) From the list of conf files, probably there is one call "default.conf" This one is a link to one of the others (4.conf or qt4.conf or 5.conf or qt5.conf). Choose the one that makes sense too you, and create a link to it.

Suppose your default file path is

/usr/lib/x86_64-linux-gnu/qt-default/qtchooser/default.conf

Create backup:

  $: cd $(dirname /usr/lib/x86_64-linux-gnu/qt-default/qtchooser/default.conf)
  $: cp -av default.conf default.conf_backup

Let's say you target is /usr/lib/x86_64-linux-gnu/qtchooser/qt5.conf

Then:

  $: sudo ln -s /usr/lib/x86_64-linux-gnu/qtchooser/qt5.conf default.conf

3) Is the path to your qmake right?

Check qmake location

  $: locate qmake | grep bin

Is the same one as indicated in your modified qtchooser/default.conf?

  $: cat /usr/lib/x86_64-linux-gnu/qtchooser/qt5.conf

If the answer is YES, then you are done. If the anser is no, then you need to modify the file:

Create backup:

  $: cd $(dirname /usr/lib/x86_64-linux-gnu/qtchooser/qt5.conf)
  $: cp -av qt5.conf qt5.conf_backup

Edit file and change path to your qmake location

  $ sudo vi qt5.conf

Now it should be done.

Answer 2

In my case it was just that qtchooser was missing the "default" configuration. I figured cmake is just executing qtchooser and looking for a "default" configuration file name. You can install any configuration file by doing the following:

qtchooser -install <arbitrary_name> <path_to_qmake>

In my case I simply provided "default" as the arbitrary name... this created the default.conf file in the appropriate locations and all is well. I don't think there is a limit to how many named versions of qt you have. If you do this as root it should work for all users.

Answer 3

In my experience, this problem is most easily solved by putting the folder containing qmake in your PATH environment variable.

Answer 4

just try "sudo apt-get install qt-sdk" it works for me

Answer 5

I solved my problem.

Looking for QT_SELECT with grep command I found that QT_SELECT is related to /usr/lib/x86_64-linux-gnu/qt-default/qtchooser/default.conf file. From the "default" file name I assumed that it is what is seen as QT_SELECT. Other configs presented with qtchooser -l are in /usr/share/qtchooser/ and /usr/lib/x86_64-linux-gnu/qtchooser directories.

Such a config file has two lines with paths. I just changed these lines, first pointing to my Qt bin directory and second pointing to my Qt lib directory. Then I could see that qtchooser -print-env shows QTTOOLDIR and QTLIBDIR to my Qt.

Then I could easily build qjson library with CMake, Qt4 was found correctly.

Answer 6

On my old RHEL distro, this did it for me:

sudo yum install qt-devel.x86_64

Just the qt-base one wouldn't work with cmake.