qsignalspy.h

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#ifndef QSIGNALSPY_H
#define QSIGNALSPY_H

#include <QtCore/qbytearray.h>
#include <QtCore/qlist.h>
#include <QtCore/qobject.h>
#include <QtCore/qmetaobject.h>
#include <QtCore/qvariant.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Test)

class QVariant;

/* ### Qt5: change the class to use regular BC mechanisms, such that we can
 * implement things like suggested in task 160192. */
class QSignalSpy: public QObject, public QList<QList<QVariant> >
{
public:
    QSignalSpy(QObject *obj, const char *aSignal)
    {
#ifdef Q_CC_BOR
        const int memberOffset = QObject::staticMetaObject.methodCount();
#else
        static const int memberOffset = QObject::staticMetaObject.methodCount();
#endif
        Q_ASSERT(obj);
        Q_ASSERT(aSignal);

        if (((aSignal[0] - '0') & 0x03) != QSIGNAL_CODE) {
            qWarning("QSignalSpy: Not a valid signal, use the SIGNAL macro");
            return;
        }

        QByteArray ba = QMetaObject::normalizedSignature(aSignal + 1);
        const QMetaObject *mo = obj->metaObject();
        int sigIndex = mo->indexOfMethod(ba.constData());
        if (sigIndex < 0) {
            qWarning("QSignalSpy: No such signal: '%s'", ba.constData());
            return;
        }

        if (!QMetaObject::connect(obj, sigIndex, this, memberOffset,
                    Qt::DirectConnection, 0)) {
            qWarning("QSignalSpy: QMetaObject::connect returned false. Unable to connect.");
            return;
        }
        sig = ba;
        initArgs(mo->method(sigIndex));
    }

    inline bool isValid() const { return !sig.isEmpty(); }
    inline QByteArray signal() const { return sig; }


    int qt_metacall(QMetaObject::Call call, int methodId, void **a)
    {
        methodId = QObject::qt_metacall(call, methodId, a);
        if (methodId < 0)
            return methodId;

        if (call == QMetaObject::InvokeMetaMethod) {
            if (methodId == 0) {
                appendArgs(a);
            }
            --methodId;
        }
        return methodId;
    }

private:
    void initArgs(const QMetaMethod &member)
    {
        QList<QByteArray> params = member.parameterTypes();
        for (int i = 0; i < params.count(); ++i) {
            int tp = QMetaType::type(params.at(i).constData());
            if (tp == QMetaType::Void)
                qWarning("Don't know how to handle '%s', use qRegisterMetaType to register it.",
                         params.at(i).constData());
            args << tp;
        }
    }

    void appendArgs(void **a)
    {
        QList<QVariant> list;
        for (int i = 0; i < args.count(); ++i) {
            QMetaType::Type type = static_cast<QMetaType::Type>(args.at(i));
            list << QVariant(type, a[i + 1]);
        }
        append(list);
    }

    // the full, normalized signal name
    QByteArray sig;
    // holds the QMetaType types for the argument list of the signal
    QList<int> args;
};

QT_END_NAMESPACE

QT_END_HEADER

#endif