source: trunk/src/corelib/kernel/qsignalmapper.cpp@ 67

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#include "qsignalmapper.h"
#ifndef QT_NO_SIGNALMAPPER
#include "qhash.h"
#include "qobject_p.h"

QT_BEGIN_NAMESPACE

class QSignalMapperPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QSignalMapper)
public:
    void _q_senderDestroyed() {
        Q_Q(QSignalMapper);
        q->removeMappings(q->sender());
    }
    QHash<QObject *, int> intHash;
    QHash<QObject *, QString> stringHash;
    QHash<QObject *, QWidget*> widgetHash;
    QHash<QObject *, QObject*> objectHash;

};


/*!
    \class QSignalMapper
    \brief The QSignalMapper class bundles signals from identifiable senders.

    \ingroup io
    \mainclass

    This class collects a set of parameterless signals, and re-emits
    them with integer, string or widget parameters corresponding to
    the object that sent the signal.

    The class supports the mapping of particular strings or integers
    with particular objects using setMapping(). The objects' signals
    can then be connected to the map() slot which will emit the
    mapped() signal with the string or integer associated with the
    original signalling object. Mappings can be removed later using
    removeMappings().

    Example: Suppose we want to create a custom widget that contains
    a group of buttons (like a tool palette). One approach is to
    connect each button's \c clicked() signal to its own custom slot;
    but in this example we want to connect all the buttons to a
    single slot and parameterize the slot by the button that was
    clicked.

    Here's the definition of a simple custom widget that has a single
    signal, \c clicked(), which is emitted with the text of the button
    that was clicked:

    \snippet doc/src/snippets/qsignalmapper/buttonwidget.h 0
    \snippet doc/src/snippets/qsignalmapper/buttonwidget.h 1

    The only function that we need to implement is the constructor:

    \snippet doc/src/snippets/qsignalmapper/buttonwidget.cpp 0
    \snippet doc/src/snippets/qsignalmapper/buttonwidget.cpp 1
    \snippet doc/src/snippets/qsignalmapper/buttonwidget.cpp 2

    A list of texts is passed to the constructor. A signal mapper is
    constructed and for each text in the list a QPushButton is
    created. We connect each button's \c clicked() signal to the
    signal mapper's map() slot, and create a mapping in the signal
    mapper from each button to the button's text. Finally we connect
    the signal mapper's mapped() signal to the custom widget's \c
    clicked() signal. When the user clicks a button, the custom
    widget will emit a single \c clicked() signal whose argument is
    the text of the button the user clicked.

    \sa QObject, QButtonGroup, QActionGroup
*/

/*!
    Constructs a QSignalMapper with parent \a parent.
*/
QSignalMapper::QSignalMapper(QObject* parent)
    : QObject(*new QSignalMapperPrivate, parent)
{
}

#ifdef QT3_SUPPORT
/*!
    \overload QSignalMapper()
    \obsolete
 */
QSignalMapper::QSignalMapper(QObject *parent, const char *name)
    : QObject(*new QSignalMapperPrivate, parent)
{
    setObjectName(QString::fromAscii(name));
}
#endif

/*!
    Destroys the QSignalMapper.
*/
QSignalMapper::~QSignalMapper()
{
}

/*!
    Adds a mapping so that when map() is signalled from the given \a
    sender, the signal mapped(\a id) is emitted.

    There may be at most one integer ID for each sender.