Help with timer and JavaScript slot.

[SPlatten]

@KroMignon , thank you, will try this now, right now before trying your suggestion the output is:

S000000000027E000000000715T09:32:03.904DL00000202Fsimon2.js[void clsScriptHelper::log]
setupForm() !!!!
S000000000028E000000000715T09:32:03.904DL00000207Fsimon2.js[void clsScriptHelper::log]
setupForm() !!!!
S000000000029E000000003405T09:32:06.594W:QObject::startTimer: Timers cannot be started from another thread

@KroMignon, thank you so much, this now works, here are the prototypes:

Q_INVOKABLE void createTimer(const QString& crstrID, const uint cuintInterval
                            ,const QString& crstrFunction);
Q_INVOKABLE void startTimer(const QString& crstrID);

And the final implementations:

/**
 * @brief clsScriptHelper::createTimer
 * @param crstrID : Constant reference to Timer ID
 * @param cuintInterval : Constant millisecond interval
 * @param crstrFunction : Constant reference to JSfile@Function
 */
void clsScriptHelper::createTimer(const QString& crstrID, const uint cuintInterval
                                 ,const QString& crstrFunction) {
    if ( crstrID.trimmed().isEmpty() == true || cuintInterval == 0
      || crstrFunction.trimmed().isEmpty() == true
      || crstrFunction.indexOf(clsXMLnode::msccScriptDelimiter) == -1 ) {
    //One or more of the parameters are invalid, do nothing
        return;
    }
    //Get Application instance
    clsMainWnd* pAppInstance(clsMainWnd::pobjGetAppWnd());
    if ( pAppInstance == nullptr ) {
    //Cannot get application instance!
        return;
    }
    //Look for registered timer
    QTimer* ptmrScript(pAppInstance->ptmrGetTimer(crstrID));
    if ( ptmrScript != nullptr ) {
    //Already registered, do nothing
        return;
    }
    //No timer locatd with that ID, its safe to proceed
    QStringList slstScript = crstrFunction.split(clsXMLnode::msccScriptDelimiter);
    mpScripts* pmpScriptsMap;
    if ( slstScript.length() == SSF_PARAM_COUNT
    && (pmpScriptsMap = clsMainWnd::pmpGetScriptsMap()) != nullptr ) {
    //Look for the script in the scripts map
        mpScripts::iterator itrScript(pmpScriptsMap->find(slstScript[SFF_FILE_IDX]));
        if ( itrScript != pmpScriptsMap->end() ) {
    //Found it, build the script up ready for the signal connection
            QString strScript(itrScript->second);
    //Get pointer to script engine
            QJSEngine* pobjScriptEng(clsJSON::pobjGetScriptEng());
    //Create new timer
            ptmrScript = new QTimer();
            ptmrScript->setInterval(cuintInterval);
    //Register the new timer using the supplied ID
            pAppInstance->registerTimer(ptmrScript, crstrID);
    //Add any globals to the script
            clsScriptHelper::pobjGetInstance()->addGlobals(pobjScriptEng);
    //Build up script function call
            QString strFile(slstScript[SFF_FILE_IDX])
                   ,strCall(slstScript[SSF_FUNCTION_IDX])
                   ,strScriptWithCall(strScript)
                   ,strFunc(strCall
                          + QString(clsDebugService::msccBrktOpen)
                          + QString(clsDebugService::msccBrktClose)
                          + QString(clsXMLnode::msccScriptFunctionTerminator));
             if ( strScriptWithCall.endsWith(clsXMLnode::msccScriptFunctionTerminator) != true ) {
                 strScriptWithCall += clsXMLnode::msccScriptFunctionTerminator;
             }
             strScriptWithCall += strFunc;
    //Create connection to timer and script
             QMetaObject::Connection cn = QObject::connect(ptmrScript
                                                         ,&QTimer::timeout
                                                         ,pobjScriptEng
                                                         ,[pobjScriptEng
                                                          ,ptmrScript
                                                          ,strFile
                                                          ,strFunc
                                                          ,strScriptWithCall]() {
                 QJSValue objResult(pobjScriptEng->evaluate(strScriptWithCall));
                 QString strError;
                 if ( objResult.isError() == true ) {
                     strError = QString("%1\n%2\n%3").arg(strFile).arg(strFunc)
                                                     .arg(objResult.toString());
                 } else {
                     QString strResult(objResult.toString());
                     if ( strResult.compare("undefined") != 0 ) {
                         strError = strResult;
                     }
                 }
                 if ( strError.isEmpty() != true ) {
                     clsXMLnode* pobjRoot(clsXMLnode::spobjGetRoot());
                     emit pobjRoot->error(strError);
                     ptmrScript->deleteLater();
                 }
            });
            QThread* pobjScriptEngThread(pobjScriptEng->thread());
            ptmrScript->moveToThread(pobjScriptEngThread);
        }
    }
}
/**
 * @brief clsScriptHelper::startTimer
 * @param crstrID : Constant reference to timer ID
 */
void clsScriptHelper::startTimer(const QString& crstrID) {
    //Get Application instance
    clsMainWnd* pAppInstance(clsMainWnd::pobjGetAppWnd());
    if ( pAppInstance == nullptr ) {
    //Cannot get application instance!
        return;
    }
    QTimer* ptmrScript(pAppInstance->ptmrGetTimer(crstrID));
    if ( ptmrScript != nullptr ) {
        QTimer::singleShot(0, ptmrScript, [ptmrScript]() { ptmrScript->start(); } );
    }
}

[kshegunov]

@SPlatten said in Help with timer and JavaScript slot.:

I would provide the call stack, but execution doesn't halt, so where would you like me to break to then get the stack?

Before doing the connect for the timer timeout. Provide the following things (in one post please):

1. The whole source of the enclosing function.
2. The call stack.
3. The output of this added just before doing the connect:

qDebug() << ptmrScript->thread() << QThread::currentThread() << ptmrScript->parent();

[KroMignon]

@SPlatten said in Help with timer and JavaScript slot.:

right now before trying your suggestion the output is:

   setupForm() !!!!
   S000000000029E000000003405T09:32:06.594W:QObject::startTimer: Timers cannot be started from another thread

Same issue, you are trying to start a QTimer from the wrong thread.
QTimer::singleShot(0, myTimer, [myTimer]() { myTimer->start(); } ); will solve this.