/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtCore module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 3 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL3 included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 3 requirements ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 2.0 or (at your option) the GNU General ** Public license version 3 or any later version approved by the KDE Free ** Qt Foundation. The licenses are as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-2.0.html and ** https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qsignalmapper.h" #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 intHash; QHash stringHash; QHash widgetHash; QHash objectHash; }; /*! \class QSignalMapper \inmodule QtCore \obsolete \brief The QSignalMapper class bundles signals from identifiable senders. \ingroup objectmodel 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 qsignalmapper/buttonwidget.h 0 \snippet qsignalmapper/buttonwidget.h 1 The only function that we need to implement is the constructor: \snippet qsignalmapper/buttonwidget.cpp 0 \snippet qsignalmapper/buttonwidget.cpp 1 \snippet 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. This class was mostly useful before lambda functions could be used as slots. The example above can be rewritten simpler without QSignalMapper by connecting to a lambda function. \snippet qsignalmapper/buttonwidget.cpp 3 \sa QObject, QButtonGroup, QActionGroup */ /*! Constructs a QSignalMapper with parent \a parent. */ QSignalMapper::QSignalMapper(QObject* parent) : QObject(*new QSignalMapperPrivate, parent) { } /*! 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. \sa mapping() */ void QSignalMapper::setMapping(QObject *sender, int id) { Q_D(QSignalMapper); d->intHash.insert(sender, id); connect(sender, SIGNAL(destroyed()), this, SLOT(_q_senderDestroyed())); } /*! Adds a mapping so that when map() is signalled from the \a sender, the signal mapped(\a text ) is emitted. There may be at most one text for each sender. */ void QSignalMapper::setMapping(QObject *sender, const QString &text) { Q_D(QSignalMapper); d->stringHash.insert(sender, text); connect(sender, SIGNAL(destroyed()), this, SLOT(_q_senderDestroyed())); } /*! Adds a mapping so that when map() is signalled from the \a sender, the signal mapped(\a widget ) is emitted. There may be at most one widget for each sender. */ void QSignalMapper::setMapping(QObject *sender, QWidget *widget) { Q_D(QSignalMapper); d->widgetHash.insert(sender, widget); connect(sender, SIGNAL(destroyed()), this, SLOT(_q_senderDestroyed())); } /*! Adds a mapping so that when map() is signalled from the \a sender, the signal mapped(\a object ) is emitted. There may be at most one object for each sender. */ void QSignalMapper::setMapping(QObject *sender, QObject *object) { Q_D(QSignalMapper); d->objectHash.insert(sender, object); connect(sender, SIGNAL(destroyed()), this, SLOT(_q_senderDestroyed())); } /*! Returns the sender QObject that is associated with the \a id. \sa setMapping() */ QObject *QSignalMapper::mapping(int id) const { Q_D(const QSignalMapper); return d->intHash.key(id); } /*! \overload mapping() */ QObject *QSignalMapper::mapping(const QString &id) const { Q_D(const QSignalMapper); return d->stringHash.key(id); } /*! \overload mapping() Returns the sender QObject that is associated with the \a widget. */ QObject *QSignalMapper::mapping(QWidget *widget) const { Q_D(const QSignalMapper); return d->widgetHash.key(widget); } /*! \overload mapping() Returns the sender QObject that is associated with the \a object. */ QObject *QSignalMapper::mapping(QObject *object) const { Q_D(const QSignalMapper); return d->objectHash.key(object); } /*! Removes all mappings for \a sender. This is done automatically when mapped objects are destroyed. \note This does not disconnect any signals. If \a sender is not destroyed then this will need to be done explicitly if required. */ void QSignalMapper::removeMappings(QObject *sender) { Q_D(QSignalMapper); d->intHash.remove(sender); d->stringHash.remove(sender); d->widgetHash.remove(sender); d->objectHash.remove(sender); } /*! This slot emits signals based on which object sends signals to it. */ void QSignalMapper::map() { map(sender()); } /*! This slot emits signals based on the \a sender object. */ void QSignalMapper::map(QObject *sender) { Q_D(QSignalMapper); if (d->intHash.contains(sender)) emit mapped(d->intHash.value(sender)); if (d->stringHash.contains(sender)) emit mapped(d->stringHash.value(sender)); if (d->widgetHash.contains(sender)) emit mapped(d->widgetHash.value(sender)); if (d->objectHash.contains(sender)) emit mapped(d->objectHash.value(sender)); } /*! \fn void QSignalMapper::mapped(int i) This signal is emitted when map() is signalled from an object that has an integer mapping set. The object's mapped integer is passed in \a i. \sa setMapping() */ /*! \fn void QSignalMapper::mapped(const QString &text) This signal is emitted when map() is signalled from an object that has a string mapping set. The object's mapped string is passed in \a text. \sa setMapping() */ /*! \fn void QSignalMapper::mapped(QWidget *widget) This signal is emitted when map() is signalled from an object that has a widget mapping set. The object's mapped widget is passed in \a widget. \sa setMapping() */ /*! \fn void QSignalMapper::mapped(QObject *object) This signal is emitted when map() is signalled from an object that has an object mapping set. The object provided by the map is passed in \a object. \sa setMapping() */ QT_END_NAMESPACE #include "moc_qsignalmapper.cpp"