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Import Causing - Qt Quick Emulation Layer Crashed

  • I have been using Qt Creator for a short while and the QML files presented themselves in the Design window just fine. Suddenly now the QML files give me an error as shown below.
    My file starts with

    import QtQuick 2.0
    import QtQuick.Window 2.10
    import QtMultimedia 5.9

    import "jsscript.js" as MyScript

    Window {
    id: splashscreen
    visible: true

    If I comment the import "jsscript.js" as MyScript in the Designer window the file displays fine.

    Is there a reason why this has started to happen. Thanks for any help.


  • Qt Champions 2018

    @gerardbyrne ,

    QtQuick designer of QtCreator doesn't support JavaScript.
    It can only change the design related function.

    Qt Documentation : Qt Quick UI Forms

    Therefore, QML file distinguish between as below two files.

    • A. Using in QtQuick designer file:

    • B. JavaScript / Signal Handlers processing file:

    It would be preferable if B file use only in Edit mode at QtCreator.
    For example:

    SampleForm.ui.qml (this file can use in QtQuickDesigner)

    import QtQuick 2.4
    Rectangle {
      id: rectangle
      color: "blue"
      property alias mouseArea: mouseArea
        MouseArea {
            id: mouseArea
            width: parent.width
            height: parent.height

    Sample.qml(this file can use Edit mode in Qt Creator)

    import QtQuick 2.4
    import "Console_log.js" as DebugLog 
    SampleForm {
      mouseArea.onClicked: {  //this file can use slot function
        DebugLog.log()    //this file can use js

    You may be also deepen my comment's understanding by below blog post.

    Qt Blog Proposal: Qt Quick Designer Workflow

  • Thank you for you help, I appreciate you taking the time to help me.

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