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DBus adaptor slots with 'const QDBusMessege &messege' argument.

  • Hi,

    In documentation of DBus in qt: "Declaring Slots in D-Bus Adaptors":" information about QDBusMessage parameter can be found.

    I need access to this parameter to be able post errors instead standard output.
    According to this documentation it should look like this (more or less):
    class SomeAdaptor : public: QDBusAbstractAdaptor
    Q_CLASSINFO("D-Bus Interface", "")
    Q_CLASSINFO("D-Bus Introspection", ""
    " <interface name="">\n"
    " <method name="myMethod">\n"
    " <arg direction="in" type="u" name="in"/>\n"
    " <arg direction="out" type="b" name="out1"/>\n"
    " <arg direction="out" type="s" name="out2"/>\n"
    " </method>\n"
    " </interface>\n"

    .... // standard stuff

    public Q_SLOTS:
    bool myMethod(uint in, QString &out2); // this version works
    bool myMethod(uint in, const QDBusMessege &messege, QString &out2); // this version doesn't work
    First version of myMethod slot works perfectly! Data are received and send back.
    But when this method is replaced with second version (as documentation suggested), it doesn't work (client is unable to call method).
    Now what should I do to make it work?
    Should I correct xml data in Q_CLASSINFO("D-Bus Introspection"? If yes, than how?
    Or maybe my declaration of slot is incorrect?
    Documentations says that this argument should be between input and output arguments like in my example.

  • You might have to update the Q_CLASSINFO() declaration as the direction of the second argument is incorrect, but from this code I'd be more worried about the fact that QDBusMessage is spelled incorrectly.

  • Yes I noticed that QDBusMessage was misspelled but only here in my post. In code in such case it would not compile.

    Anyway I've checked all classes related with DBus and I've found nice clear solution, much better than this extra argument. There is class "QDBusContext": which is used like this.
    @class ActualDBusObjectNotAdaptor : public QObject, protected QDBusContext {
    // rest is the same

    bool ActualDBusObjectNotAdaptor::myMethod(uint in, QString &out2) {
    if (in<0) {
    sendErrorReply("Error.string", "User readable messege");
    So extra parameter is not needed.
    Apparently "here in documentations": is mistake (it doesn't work as specified) probably some leftover after older version or at least it is incomplete.
    I will file a bug report.

    Thanks for trying help me.

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