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[solved] Trying to link my own static libarry

  • Hello guys!
    I've googled this evening converting my projects to Qt Creator.
    So far I managed to compile one static library, but it fails to link with another library I need it in.

    I have added these in my project file:
    INCLUDEPATH += "C:\Users\Tapsa"
    DEPENDPATH += "C:\Users\Tapsa"
    LIBS += "C:\Users\Tapsa\pcrio\release\libpcrio.a"

    I still get undefined reference to that library.
    I googled that those 3 lines, would solve this problem, but no.

    What else I need to do to link another Qt project?

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    Might be a silly question but did you check that both libraries are for the same architecture ?

  • Yes it seems so. Both use same qmake build commands.

    qmake.exe C:\Users\Tapsa\pcrio\ -r -spec win32-g++
    qmake.exe C:\Users\Tapsa\genieutils\ -r -spec win32-g++

    Also whenever I set pcrio as a dependency for genieutils, it unchecks on itself.

    Earlier I accidentally created app from the pcrio lib at first.
    I then created lib project on top of it later. Is that a problem?

  • Lifetime Qt Champion

    I'm not following you here, what did you create in what order ?

  • I had used to compile my projects using CMake and MinGW.
    Then I downloaded and installed Qt Creator and compiled boost with zlib.
    I applied "qmake -project" "qmake" in my two libraries.
    I built my pcrio library and noticed that it output an executable.
    Then I created a library project with the same name over the pcrio and it compiled into library fine.
    I added build and library paths into genieutils project file pointing to pcrio and it gives me undefined references to my pcrio library.

    My sources are on GitHub so if somebody wants I can push my progress there to look at.

  • Lifetime Qt Champion

    If you have a cmake project working why not continue to use cmake ?

  • Umm there was no option "create project from existing source using CMake".

  • Lifetime Qt Champion

    Because there's no need for that, just do "Open File or Project" and open your top-level CMakeFile.txt

  • I did try that, but Qt didn't read any other files in :(
    There are some errors too. I need to clear them first.

    CMake Error at cmake/FindCheck.cmake:35 (MESSAGE):
    Could NOT find CHECK

  • Lifetime Qt Champion

    Sorry, I meant CMakeLists.txt

  • Aye. Thanks.
    I managed to compile pcrio and zlib using CMakeLists.txt with Qt.
    Why Qt only shows the CMakeLists.txt and no other files whatsoever?

    It appears I managed to build both my libraries.
    I had to manually tell both library files to CMake Wizard -.-


    How can it be so stupid that it can't see the files unless I toss them on its face?

  • Lifetime Qt Champion

    How do you list the files your CMakeLists.txt ?


    For genieutils I passed some arguments to CMake:

    Is there a better way?

  • Lifetime Qt Champion

    You could try to use CMake's finder script for boost and zlib

  • Yeah, but those fail.
    find_package(Boost 1.58 COMPONENTS iostreams REQUIRED)
    Even if I give as additional argument the boost library folder, it still fails to find it.
    It hasn't complained about zlib yet for some reason.

    Since Qt doesn't save additional arguments anywhere, do I need to put them into the CMakeLists.txt? I used batch scripts to compile my builds before.
    Other people who compile my code probably have different paths. What is the best way to extract custom paths so that working with github is easy?

    I have much more questions about Qt designer etc. You seem to be Qt professional. Do you suggest adding new topics as I proceed coding and googling or can you answer some Qt GUI questions?

  • Lifetime Qt Champion

    You would have to give cmake additional paths to search for boost, but it's not something that you can really make generic since on Windows, there's no common place like on *nix systems. Using -DCMAKE_PREFIX_PATH can help.

    I can answer them however for other questions not directly related to this thread, you should rather open new topics. That will keep the forum easy to use and search for other users.

  • LOL are you kidding me :D I had these lines AFTER find boost:

    set(Boost_USE_STATIC_LIBS ON)

    Normally I don't even use this make file, but instead I use another for the actual program that uses these libraries. I moved those options above find boost and it works like a charm.

    Quick question: what is the fastest list box for over 10 000 items? It needs to have multiple selections and just be basic looking list box. Either it is not list view, or it needs to be adjusted a lot to achieve basic list box look.

  • Lifetime Qt Champion

    What do you mean by "list box" ?

  • Like the one in left in this picture:
    You can see it has bunch of string items (with void pointers to data) and you can select many at once.

    It's from this program:

  • Lifetime Qt Champion

    If you are talking about the widget on the left, it looks like a QListView with extended selection enabled. What makes you think it needs to be adjusted a lot ?

  • Nice, now I can rebuild my GUI with Qt.
    Each item in that list view has its own rounded selection area with dotted outline.
    It doesn't look/feel same to wxWidgets list box at all. Default QListView allows items to be moved around and edited their labels too. I disabled moving and label-editing. But if you say that QlistView can be made to look and feel like wxWidgets list box, then I will figure it out myself.

    You can mark this as solved. I don't know how to mark it.

  • Lifetime Qt Champion

    If you need some special visualization then you can subclass QStyledItemDelegate. Apart from that, you have to ponder whether you want to keep the current look and feel of your application or have it more close to what the platform you are targeting offers.

    To mark the thread as solved, you can simply edit the title and prepend [solved] :)

    Also, consider up-voting the answer(s) that helped you, so other forum users may find them more easily

  • Thank you.
    I'll be subclassing text/combo/check boxes as well.

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