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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qmlconnection_p.h"
+
+#include <qmlexpression.h>
+#include <qmlboundsignal_p.h>
+#include <qmlcontext.h>
+
+#include <QtCore/qdebug.h>
+
+#include <private/qobject_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QmlConnectionPrivate : public QObjectPrivate
+{
+public:
+ QmlConnectionPrivate() : boundsignal(0), signalSender(0), scriptset(false), componentcomplete(false) {}
+
+ QmlBoundSignal *boundsignal;
+ QObject *signalSender;
+ QmlScriptString script;
+ bool scriptset;
+ QString signal;
+ bool componentcomplete;
+};
+
+/*!
+ \qmlclass Connection QmlConnection
+ \brief A Connection object describes generalized connections to signals.
+
+ When connecting to signals in QML, the usual way is to create an
+ "on<Signal>" handler that reacts when a signal is received, like this:
+
+ \qml
+ MouseRegion {
+ onClicked: { foo(x+123,y+456) }
+ }
+ \endqml
+
+ However, in some cases, it is not possible to connect to a signal in this
+ way. For example, JavaScript-in-HTML style signal properties do not allow:
+
+ \list
+ \i connecting to signals with the same name but different parameters
+ \i conformance checking that parameters are correctly named
+ \i multiple connections to the same signal
+ \i connections outside the scope of the signal sender
+ \i signals in classes with coincidentally-named on<Signal> properties
+ \endlist
+
+ When any of these are needed, the Connection object can be used instead.
+
+ For example, the above code can be changed to use a Connection object,
+ like this:
+
+ \qml
+ MouseRegion {
+ Connection {
+ signal: "clicked(x,y)"
+ script: { foo(x+123,y+456) }
+ }
+ }
+ \endqml
+
+ More generally, the Connection object can be a child of some other object than
+ the sender of the signal, and the script is the default attribute:
+
+ \qml
+ MouseRegion {
+ id: mr
+ }
+ ...
+ Connection {
+ sender: mr
+ signal: "clicked(x,y)"
+ script: { foo(x+123,y+456) }
+ }
+ \endqml
+*/
+
+/*!
+ \internal
+ \class QmlConnection
+ \brief The QmlConnection class describes generalized connections to signals.
+
+*/
+QmlConnection::QmlConnection(QObject *parent) :
+ QObject(*(new QmlConnectionPrivate), parent)
+{
+}
+
+QmlConnection::~QmlConnection()
+{
+ Q_D(QmlConnection);
+ delete d->boundsignal;
+}
+
+/*!
+ \qmlproperty Object Connection::sender
+ This property holds the object that sends the signal.
+
+ By default, the sender is assumed to be the parent of the Connection.
+*/
+QObject *QmlConnection::signalSender() const
+{
+ Q_D(const QmlConnection);
+ return d->signalSender ? d->signalSender : parent();
+}
+
+void QmlConnection::setSignalSender(QObject *obj)
+{
+ Q_D(QmlConnection);
+ if (d->signalSender == obj)
+ return;
+ disconnectIfValid();
+ d->signalSender = obj;
+ connectIfValid();
+}
+
+void QmlConnection::connectIfValid()
+{
+ Q_D(QmlConnection);
+ if (!d->componentcomplete)
+ return;
+ // boundsignal must not exist
+ if ((d->signalSender || parent()) && !d->signal.isEmpty() && d->scriptset) {
+ // create
+ // XXX scope?
+ int sigIdx = -1;
+ int lparen = d->signal.indexOf(QLatin1Char('('));
+ QList<QByteArray> sigparams;
+ if (lparen >= 0 && d->signal.length() > lparen+2) {
+ QStringList l = d->signal.mid(lparen+1,d->signal.length()-lparen-2).split(QLatin1Char(','));
+ foreach (const QString &s, l) {
+ sigparams.append(s.trimmed().toUtf8());
+ }
+ }
+ QString signalname = d->signal.left(lparen);
+ QObject *sender = d->signalSender ? d->signalSender : parent();
+ const QMetaObject *mo = sender->metaObject();
+ int methods = mo->methodCount();
+ for (int ii = 0; ii < methods; ++ii) {
+ QMetaMethod method = mo->method(ii);
+ QString methodName = QString::fromUtf8(method.signature());
+ int idx = methodName.indexOf(QLatin1Char('('));
+ methodName = methodName.left(idx);
+ if (methodName == signalname && (lparen<0 || method.parameterNames() == sigparams)) {
+ sigIdx = ii;
+ break;
+ }
+ }
+ if (sigIdx < 0) {
+ // Cannot usefully warn, since could be in middle of
+ // changing sender and signal.
+ // XXX need state change transactions to do better
+ return;
+ }
+
+ d->boundsignal = new QmlBoundSignal(qmlContext(this), d->script.script(), sender, mo->method(sigIdx), this);
+ }
+}
+
+void QmlConnection::disconnectIfValid()
+{
+ Q_D(QmlConnection);
+ if (!d->componentcomplete)
+ return;
+ if ((d->signalSender || parent()) && !d->signal.isEmpty() && d->scriptset) {
+ // boundsignal must exist
+ // destroy
+ delete d->boundsignal;
+ d->boundsignal = 0;
+ }
+}
+
+void QmlConnection::componentComplete()
+{
+ Q_D(QmlConnection);
+ d->componentcomplete=true;
+ connectIfValid();
+}
+
+
+/*!
+ \qmlproperty script Connection::script
+ This property holds the JavaScript executed whenever the signal is sent.
+
+ This is the default attribute of Connection.
+*/
+QmlScriptString QmlConnection::script() const
+{
+ Q_D(const QmlConnection);
+ return d->script;
+}
+
+void QmlConnection::setScript(const QmlScriptString& script)
+{
+ Q_D(QmlConnection);
+ if ((d->signalSender || parent()) && !d->signal.isEmpty()) {
+ if (!d->scriptset) {
+ // mustn't exist - create
+ d->scriptset = true;
+ d->script = script;
+ connectIfValid();
+ } else {
+ // must exist - update
+ d->script = script;
+ d->boundsignal->expression()->setExpression(script.script());
+ }
+ } else {
+ d->scriptset = true;
+ d->script = script;
+ }
+}
+
+/*!
+ \qmlproperty string Connection::signal
+ This property holds the signal from the sender to which the script is attached.
+
+ The signal's formal parameter names must be given in parentheses:
+
+ \qml
+Connection {
+ signal: "clicked(x,y)"
+ script: { ... }
+}
+ \endqml
+*/
+QString QmlConnection::signal() const
+{
+ Q_D(const QmlConnection);
+ return d->signal;
+}
+
+void QmlConnection::setSignal(const QString& sig)
+{
+ Q_D(QmlConnection);
+ if (d->signal == sig)
+ return;
+ disconnectIfValid();
+ d->signal = sig;
+ connectIfValid();
+}
+
+QML_DEFINE_TYPE(Qt,4,6,Connection,QmlConnection)
+
+QT_END_NAMESPACE
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