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QML file from extension plugin -> "Unknown component"

  • Hi all,

    I still manage to build properly a custom QML lib, so I built an extension plugin.

    Everything works fine except...code completion within QtCreator. But it works during execution.

    My custom QML type (defined in a QML file, not a QML binding from C++) isn't recognized by the QML editor. It's very frustrating.

    I tried many never works.

    Here's my project's structure :

    -- app
    ---- some things
    ---- qml.qrc
    ------ main.qml // error M300
    -- libs
    ---- customquick // Folder of QML plugins
    ------ controls // my extension plugin
    -------- customquickcontrolsplugin.(h/cpp)
    -------- gridmenulogic.(h/cpp) // C++ binding class
    -------- GridMenu.qml // the type which isn't recognized in main.qml
    -------- qmldir

    My qmldir :
    @module customquick.controls
    GridMenu 1.0 GridMenu.qml
    plugin customquickcontrolsplugin
    classname CustomQuickControlsPlugin

    @import QtQuick 2.2
    import QtQuick.Window 2.1
    import customquick.controls 1.0

    Window {
    visible: true
    width: 360
    height: 360

    GridMenu { *// <-- M300 error*
        id: menu
        anchors.fill: parent


    @import QtQuick 2.0
    import customquick.controls 1.0

    Item {
    width: 100
    height: 80

    GridMenuLogic {


    And my CustomQuickControlsPlugin class :
    @void CustomQuickControlsPlugin::registerTypes(const char *uri)
    // @uri controls
    Q_ASSERT(uri == QLatin1String("customquick.controls"));
    qmlRegisterType<GridMenuLogic>(uri, 1, 0, "GridMenuLogic");

    The project copies the .qml files to the build directory and I setted the "QML2_IMPORT_PATH" environment var. But GridMenu is still underlined in main.qml...

    I works with QtCreator 3.2.0 and Ubuntu 14.04.

    Thanks for your help.

  • Hi,

    Did you try put this line in main.qml?
    #import GridMenuLogic 1.0


  • Thanks for your reply.

    Yes, it doesn't work, the engine deosn't recognize it as a module.

    I tried to put GridMenu.qml in main.qml folder, and import with

    "import GridMenu.qml"

    but it failed too.

  • Well,

    Try to put GridMenu folder's path in a "import" clause, like this:

    #import "../libs/customquick/controls".


  • Well well well... It works...partially :p

    Firstly, I got a...warning (in french) :
    "The QML module contains some C++ modules, reading type informations...".

    So, GridMenu is recognized by the code model, but if I run the program it doesn't work anymore :

    "QQmlApplicationEngine failed to load component
    qrc:///main.qml:5 "../libs/customquick/controls": no such directory"

    Maybe because main.qml is within a Qt resource file ?

    EDIT :'s because the qrc file. If I copy main.qml in the build directory and I delete it from the resource file, It works. The "import" is still yellow underlined.

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