QNetworkSession Class Reference

The QNetworkSession class provides control over the system's access points and enables session management for cases when multiple clients access the same access point. More...

#include <qnetworksession.h>

Inheritance diagram for QNetworkSession:

Public Types
enum	SessionError {   UnknownSessionError = 0, SessionAbortedError, RoamingError, OperationNotSupportedError,   InvalidConfigurationError }
	This enum describes the session errors that can occur. More...
enum	State {   Invalid = 0, NotAvailable, Connecting, Connected,   Closing, Disconnected, Roaming }
	This enum describes the connectivity state of the session. More...

Public Slots
void	accept ()
	Instructs the session to permanently accept the new access point. More...
void	close ()
	Decreases the session counter on the associated network configuration. More...
void	ignore ()
	This function indicates that the application does not wish to roam the session. More...
void	migrate ()
	Instructs the session to roam to the new access point. More...
void	open ()
	Creates an open session which increases the session counter on the underlying network interface. More...
void	reject ()
	The new access point is not suitable for the application. More...
void	stop ()
	Invalidates all open sessions against the network interface and therefore stops the underlying network interface. More...
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. More...

Signals
void	closed ()
	This signal is emitted when the network session has been closed. More...
void	error (QNetworkSession::SessionError)
	This signal is emitted after an error occurred. More...
void	newConfigurationActivated ()
	This signal is emitted once the session has roamed to the new access point. More...
void	opened ()
	This signal is emitted when the network session has been opened. More...
void	preferredConfigurationChanged (const QNetworkConfiguration &config, bool isSeamless)
	This signal is emitted when the preferred configuration/access point for the session changes. More...
void	stateChanged (QNetworkSession::State)
	This signal is emitted whenever the state of the network session changes. More...
Signals inherited from QObject
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...

Public Functions
quint64	activeTime () const
	Returns the number of seconds that the session has been active. More...
quint64	bytesReceived () const
	Returns the amount of data received in bytes; otherwise 0. More...
quint64	bytesWritten () const
	Returns the amount of data sent in bytes; otherwise 0. More...
QNetworkConfiguration	configuration () const
	Returns the QNetworkConfiguration that this network session object is based on. More...
SessionError	error () const
	Returns the type of error that last occurred. More...
QString	errorString () const
	Returns a human-readable description of the last device error that occurred. More...
QNetworkInterface	interface () const
	Returns the network interface that is used by this session. More...
bool	isOpen () const
	Returns true if this session is open. More...
	QNetworkSession (const QNetworkConfiguration &connConfig, QObject *parent=0)
	Constructs a session based on connectionConfig with the given parent. More...
QVariant	sessionProperty (const QString &key) const
	Returns the value for property key. More...
void	setSessionProperty (const QString &key, const QVariant &value)
	Sets the property value on the session. More...
State	state () const
	Returns the state of the session. More...
bool	waitForOpened (int msecs=30000)
	Waits until the session has been opened, up to msecs milliseconds. More...
virtual	~QNetworkSession ()
	Frees the resources associated with the QNetworkSession object. More...
Public Functions inherited from QObject
bool	blockSignals (bool b)
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). More...
const QObjectList &	children () const
	Returns a list of child objects. More...
bool	connect (const QObject *sender, const char *signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char *signal=0, const QObject *receiver=0, const char *member=0)
bool	disconnect (const QObject *receiver, const char *member=0)
void	dumpObjectInfo ()
	Dumps information about signal connections, etc. More...
void	dumpObjectTree ()
	Dumps a tree of children to the debug output. More...
QList< QByteArray >	dynamicPropertyNames () const
	Returns the names of all properties that were dynamically added to the object using setProperty(). More...
virtual bool	event (QEvent *)
	This virtual function receives events to an object and should return true if the event e was recognized and processed. More...
virtual bool	eventFilter (QObject *, QEvent *)
	Filters events if this object has been installed as an event filter for the watched object. More...
template<typename T >
T	findChild (const QString &aName=QString()) const
	Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. More...
template<typename T >
QList< T >	findChildren (const QString &aName=QString()) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. More...
template<typename T >
QList< T >	findChildren (const QRegExp &re) const
bool	inherits (const char *classname) const
	Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false. More...
void	installEventFilter (QObject *)
	Installs an event filter filterObj on this object. More...
bool	isWidgetType () const
	Returns true if the object is a widget; otherwise returns false. More...
void	killTimer (int id)
	Kills the timer with timer identifier, id. More...
virtual const QMetaObject *	metaObject () const
	Returns a pointer to the meta-object of this object. More...
void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children. More...
QString	objectName () const
QObject *	parent () const
	Returns a pointer to the parent object. More...
QVariant	property (const char *name) const
	Returns the value of the object's name property. More...
Q_INVOKABLE	QObject (QObject *parent=0)
	Constructs an object with parent object parent. More...
void	removeEventFilter (QObject *)
	Removes an event filter object obj from this object. More...
void	setObjectName (const QString &name)
void	setParent (QObject *)
	Makes the object a child of parent. More...
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value. More...
void	setUserData (uint id, QObjectUserData *data)
bool	signalsBlocked () const
	Returns true if signals are blocked; otherwise returns false. More...
int	startTimer (int interval)
	Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. More...
QThread *	thread () const
	Returns the thread in which the object lives. More...
QObjectUserData *	userData (uint id) const
virtual	~QObject ()
	Destroys the object, deleting all its child objects. More...

Protected Functions
virtual void	connectNotify (const char *signal)
	This function is required to detect whether the client wants to control the roaming process. More...
virtual void	disconnectNotify (const char *signal)
	This function is called when the client disconnects from the preferredConfigurationChanged() signal. More...
Protected Functions inherited from QObject
virtual void	childEvent (QChildEvent *)
	This event handler can be reimplemented in a subclass to receive child events. More...
virtual void	customEvent (QEvent *)
	This event handler can be reimplemented in a subclass to receive custom events. More...
	QObject (QObjectPrivate &dd, QObject *parent=0)
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal. More...
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. More...
int	senderSignalIndex () const
virtual void	timerEvent (QTimerEvent *)
	This event handler can be reimplemented in a subclass to receive timer events for the object. More...

Properties
QNetworkSessionPrivate *	d

Friends
class	QNetworkSessionPrivate

Additional Inherited Members
Static Public Functions inherited from QObject
static bool	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *member, Qt::ConnectionType=Qt::AutoConnection)
	Creates a connection of the given type from the signal in the sender object to the method in the receiver object. More...
static bool	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
	Disconnects signal in object sender from method in object receiver. More...
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static uint	registerUserData ()
static QString	tr (const char *sourceText, const char *comment=0, int n=-1)
static QString	trUtf8 (const char *sourceText, const char *comment=0, int n=-1)
Static Public Variables inherited from QObject
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...
Protected Variables inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject
Related Functions inherited from QObject
T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QRegExp &regExp)()
T *	qobject_cast (QObject *object)
	QObjectList
void *	qt_find_obj_child (QObject *parent, const char *type, const QString &name)
	Returns a pointer to the object named name that inherits type and with a given parent. More...

Detailed Description

The QNetworkSession class provides control over the system's access points and enables session management for cases when multiple clients access the same access point.

Since

4.7

Attention

Module: QtNetwork

A QNetworkSession enables control over the system's network interfaces. The session's configuration parameter are determined via the QNetworkConfiguration object to which it is bound. Depending on the type of the session (single access point or service network) a session may be linked to one or more network interfaces. By means of opening and closing of network sessions a developer can start and stop the systems network interfaces. If the configuration represents multiple access points (see QNetworkConfiguration::ServiceNetwork ) more advanced features such as roaming may be supported.

QNetworkSession supports session management within the same process and depending on the platform's capabilities may support out-of-process sessions. If the same network configuration is used by multiple open sessions the underlying network interface is only terminated once the last session has been closed.

Roaming

Applications may connect to the preferredConfigurationChanged() signal in order to receive notifications when a more suitable access point becomes available. In response to this signal the application must either initiate the roaming via migrate() or ignore() the new access point. Once the session has roamed the newConfigurationActivated() signal is emitted. The application may now test the carrier and must either accept() or reject() it. The session will return to the previous access point if the roaming was rejected. The subsequent state diagram depicts the required state transitions.

Some platforms may distinguish forced roaming and application level roaming (ALR). ALR implies that the application controls (via migrate(), ignore(), accept() and reject()) whether a network session can roam from one access point to the next. Such control is useful if the application maintains stateful socket connections and wants to control the transition from one interface to the next. Forced roaming implies that the system automatically roams to the next network without consulting the application. This has the advantage that the application can make use of roaming features without actually being aware of it. It is expected that the application detects that the underlying socket is broken and automatically reconnects via the new network link.

If the platform supports both modes of roaming, an application indicates its preference by connecting to the preferredConfigurationChanged() signal. Connecting to this signal means that the application wants to take control over the roaming behavior and therefore implies application level roaming. If the client does not connect to the preferredConfigurationChanged(), forced roaming is used. If forced roaming is not supported the network session will not roam by default.

Some applications may want to suppress any form of roaming altogether. Possible use cases may be high priority downloads or remote services which cannot handle a roaming enabled client. Clients can suppress roaming by connecting to the preferredConfigurationChanged() signal and answer each signal emission with ignore().

See also

QNetworkConfiguration, QNetworkConfigurationManager

Definition at line 71 of file qnetworksession.h.

Enumerations

SessionError

enum QNetworkSession::SessionError

This enum describes the session errors that can occur.

• UnknownSessionError An unidentified error occurred.
• SessionAbortedError The session was aborted by the user or system.
• RoamingError The session cannot roam to a new configuration.
• OperationNotSupportedError The operation is not supported for current configuration.
• InvalidConfigurationError The operation cannot currently be performed for the current configuration.

Enumerator
UnknownSessionError
SessionAbortedError
RoamingError
OperationNotSupportedError
InvalidConfigurationError

Definition at line 86 of file qnetworksession.h.

                      {
        UnknownSessionError = 0,
        SessionAbortedError,
        RoamingError,
        OperationNotSupportedError,
        InvalidConfigurationError
    };

State

enum QNetworkSession::State

This enum describes the connectivity state of the session.

If the session is based on a single access point configuration the state of the session is the same as the state of the associated network interface.

• Invalid The session is invalid due to an invalid configuration. This may happen due to a removed access point or a configuration that was invalid to begin with.
• NotAvailable The session is based on a defined but not yet discovered QNetworkConfiguration (see QNetworkConfiguration::StateFlag ).
• Connecting The network session is being established.
• Connected The network session is connected. If the current process wishes to use this session it has to register its interest by calling open(). A network session is considered to be ready for socket operations if it isOpen() and connected.
• Closing The network session is in the process of being shut down.
• Disconnected The network session is not connected. The associated QNetworkConfiguration has the state QNetworkConfiguration::Discovered.
• Roaming The network session is roaming from one access point to another access point.

Enumerator
Invalid
NotAvailable
Connecting
Connected
Closing
Disconnected
Roaming

Definition at line 76 of file qnetworksession.h.

               {
        Invalid = 0,
        NotAvailable,
        Connecting,
        Connected,
        Closing,
        Disconnected,
        Roaming
    };

Constructors and Destructors

QNetworkSession()

QNetworkSession::QNetworkSession ( const QNetworkConfiguration &  connectionConfig, QObject *  parent = 0  )

explicit

Constructs a session based on connectionConfig with the given parent.

See also

QNetworkConfiguration

Definition at line 261 of file qnetworksession.cpp.

Referenced by QSharedNetworkSessionManager::getSession().

    : QObject(parent), d(0)
{
    // invalid configuration
    if (!connectionConfig.identifier().isEmpty()) {
        foreach (QBearerEngine *engine, qNetworkConfigurationManagerPrivate()->engines()) {
            if (engine->hasIdentifier(connectionConfig.identifier())) {
                d = engine->createSessionBackend();
                d->q = this;
                d->publicConfig = connectionConfig;
                d->syncStateWithInterface();
                connect(d, SIGNAL(quitPendingWaitsForOpened()), this, SIGNAL(opened()));
                connect(d, SIGNAL(error(QNetworkSession::SessionError)),
                        this, SIGNAL(error(QNetworkSession::SessionError)));
                connect(d, SIGNAL(stateChanged(QNetworkSession::State)),
                        this, SIGNAL(stateChanged(QNetworkSession::State)));
                connect(d, SIGNAL(closed()), this, SIGNAL(closed()));
                connect(d, SIGNAL(preferredConfigurationChanged(QNetworkConfiguration,bool)),
                        this, SIGNAL(preferredConfigurationChanged(QNetworkConfiguration,bool)));
                connect(d, SIGNAL(newConfigurationActivated()),
                        this, SIGNAL(newConfigurationActivated()));
                break;
            }
        }
    }

    qRegisterMetaType<QNetworkSession::State>();
    qRegisterMetaType<QNetworkSession::SessionError>();
}

~QNetworkSession()

QNetworkSession::~QNetworkSession ( )

virtual

Frees the resources associated with the QNetworkSession object.

Definition at line 294 of file qnetworksession.cpp.

{
    delete d;
}

Functions

accept

void QNetworkSession::accept ( )

slot

Instructs the session to permanently accept the new access point.

Once this function has been called the session may not return to the old access point.

The old access point may be closed in the process if there are no other network sessions for it. Therefore any open socket that still uses the old access point may become unusable and should be closed before completing the migration.

Definition at line 630 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    if (d)
        d->accept();
}

activeTime()

quint64 QNetworkSession::activeTime

(

)

const

Returns the number of seconds that the session has been active.

Definition at line 691 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    return d ? d->activeTime() : Q_UINT64_C(0);
}

bytesReceived()

quint64 QNetworkSession::bytesReceived

(

)

const

Returns the amount of data received in bytes; otherwise 0.

This field value includes the usage across all open network sessions which use the same network interface.

If the session is based on a service network configuration the number of sent bytes across all active member configurations are returned.

This function may not always be supported on all platforms and returns 0. The platform capability can be detected via QNetworkConfigurationManager::DataStatistics.

Note

On some platforms this function may run the main event loop.

Definition at line 683 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    return d ? d->bytesReceived() : Q_UINT64_C(0);
}

bytesWritten()

quint64 QNetworkSession::bytesWritten

(

)

const

Returns the amount of data sent in bytes; otherwise 0.

This field value includes the usage across all open network sessions which use the same network interface.

If the session is based on a service network configuration the number of sent bytes across all active member configurations are returned.

This function may not always be supported on all platforms and returns 0. The platform capability can be detected via QNetworkConfigurationManager::DataStatistics.

Note

On some platforms this function may run the main event loop.

Definition at line 664 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    return d ? d->bytesWritten() : Q_UINT64_C(0);
}

close

void QNetworkSession::close ( )

slot

Decreases the session counter on the associated network configuration.

If the session counter reaches zero the active network interface is shut down. This also means that state() will only change from Connected to Disconnected if the current session was the last open session.

If the platform does not support out-of-process sessions calling this function does not stop the interface. In this case stop() has to be used to force a shut down. The platform capabilities can be detected via QNetworkConfigurationManager::capabilities().

Note that this call is asynchronous. Depending on the outcome of this call the results can be enquired by connecting to the stateChanged(), opened() or error() signals.

See also

open(), stop(), isOpen()

Definition at line 381 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::~QNetworkSessionPrivate().

{
    if (d)
        d->close();
}

closed

void QNetworkSession::closed ( )

signal

This signal is emitted when the network session has been closed.

Referenced by QNetworkSession(), and QNetworkSessionPrivate::setPrivateConfiguration().

configuration()

QNetworkConfiguration QNetworkSession::configuration

(

)

const

Returns the QNetworkConfiguration that this network session object is based on.

See also

QNetworkConfiguration

Definition at line 408 of file qnetworksession.cpp.

Referenced by QNetworkAccessManagerPrivate::_q_networkSessionClosed(), QNetworkAccessManager::configuration(), and QNetworkAccessBackend::start().

{
    return d ? d->publicConfig : QNetworkConfiguration();
}

connectNotify()

void QNetworkSession::connectNotify ( const char *  signal )

protectedvirtual

This function is required to detect whether the client wants to control the roaming process.

Warning

This function is not part of the public interface.

If he connects to preferredConfigurationChanged() signal he intends to influence it. Otherwise QNetworkSession always roams without registering this session as a stakeholder in the roaming process.

For more details check the Forced vs ALR roaming section in the QNetworkSession class description.

Reimplemented from QObject.

Definition at line 710 of file qnetworksession.cpp.

{
    QObject::connectNotify(signal);

    if (!d)
        return;

    //check for preferredConfigurationChanged() signal connect notification
    //This is not required on all platforms
    if (qstrcmp(signal, SIGNAL(preferredConfigurationChanged(QNetworkConfiguration,bool))) == 0)
        d->setALREnabled(true);
}

disconnectNotify()

void QNetworkSession::disconnectNotify ( const char *  signal )

protectedvirtual

This function is called when the client disconnects from the preferredConfigurationChanged() signal.

Warning

This function is not part of the public interface.

See also

connectNotify()

Reimplemented from QObject.

Definition at line 734 of file qnetworksession.cpp.

{
    QObject::disconnectNotify(signal);

    if (!d)
        return;

    //check for preferredConfigurationChanged() signal disconnect notification
    //This is not required on all platforms
    if (qstrcmp(signal, SIGNAL(preferredConfigurationChanged(QNetworkConfiguration,bool))) == 0)
        d->setALREnabled(false);
}

error() [1/2]

QNetworkSession::SessionError QNetworkSession::error

(

)

const

Returns the type of error that last occurred.

See also

state(), errorString()

Definition at line 470 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivateImpl::errorString(), open(), QNetworkSession(), and waitForOpened().

{
    return d ? d->error() : InvalidConfigurationError;
}

error [2/2]

void QNetworkSession::error ( QNetworkSession::SessionError  error )

signal

This signal is emitted after an error occurred.

The error parameter describes the error that occurred.

See also

error(), errorString()

errorString()

QString QNetworkSession::errorString

(

)

const

Returns a human-readable description of the last device error that occurred.

See also

error()

Definition at line 481 of file qnetworksession.cpp.

{
    return d ? d->errorString() : tr("Invalid configuration.");
}

ignore

void QNetworkSession::ignore ( )

slot

This function indicates that the application does not wish to roam the session.

See also

migrate()

Definition at line 614 of file qnetworksession.cpp.

{
    // Needed on at least Symbian platform: the roaming must be explicitly
    // ignore()'d or migrate()'d
    if (d)
        d->ignore();
}

interface()

QNetworkInterface QNetworkSession::interface

(

)

const

Returns the network interface that is used by this session.

This function only returns a valid QNetworkInterface when this session is Connected .

The returned interface may change as a result of a roaming process.

Note: this function does not work in Symbian emulator due to the way the connectivity is emulated on Windows.

See also

state()

Definition at line 426 of file qnetworksession.cpp.

{
    return d ? d->currentInterface() : QNetworkInterface();
}

isOpen()

bool QNetworkSession::isOpen

(

)

const

Returns true if this session is open.

If the number of all open sessions is greater than zero the underlying network interface will remain connected/up.

The session can be controlled via open() and close().

Definition at line 438 of file qnetworksession.cpp.

{
    return d ? d->isOpen : false;
}

migrate

void QNetworkSession::migrate ( )

slot

Instructs the session to roam to the new access point.

The old access point remains active until the application calls accept().

The newConfigurationActivated() signal is emitted once roaming has been completed.

See also

accept()

Definition at line 603 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    if (d)
        d->migrate();
}

newConfigurationActivated

void QNetworkSession::newConfigurationActivated ( )

signal

This signal is emitted once the session has roamed to the new access point.

The application may reopen its socket and test the suitability of the new network link. Subsequently it must either accept() or reject() the new access point.

See also

accept(), reject()

Referenced by QNetworkSession(), and QNetworkSessionPrivate::setPrivateConfiguration().

open

void QNetworkSession::open ( )

slot

Creates an open session which increases the session counter on the underlying network interface.

The system will not terminate a network interface until the session reference counter reaches zero. Therefore an open session allows an application to register its use of the interface.

As a result of calling open() the interface will be started if it is not connected/up yet. Some platforms may not provide support for out-of-process sessions. On such platforms the session counter ignores any sessions held by another process. The platform capabilities can be detected via QNetworkConfigurationManager::capabilities().

Note that this call is asynchronous. Depending on the outcome of this call the results can be enquired by connecting to the stateChanged(), opened() or error() signals.

It is not a requirement to open a session in order to monitor the underlying network interface.

See also

close(), stop(), isOpen()

Definition at line 316 of file qnetworksession.cpp.

{
    if (d)
        d->open();
    else
        emit error(InvalidConfigurationError);
}

opened

void QNetworkSession::opened ( )

signal

This signal is emitted when the network session has been opened.

The underlying network interface will not be shut down as long as the session remains open. Note that this feature is dependent on system wide session support.

Referenced by QNetworkSession().

preferredConfigurationChanged

void QNetworkSession::preferredConfigurationChanged ( const QNetworkConfiguration &  config, bool  isSeamless  )

signal

This signal is emitted when the preferred configuration/access point for the session changes.

Only sessions which are based on service network configurations may emit this signal. config can be used to determine access point specific details such as proxy settings and isSeamless indicates whether roaming will break the sessions IP address.

As a consequence to this signal the application must either start the roaming process by calling migrate() or choose to ignore() the new access point.

If the roaming process is non-seamless the IP address will change which means that a socket becomes invalid. However seamless mobility can ensure that the local IP address does not change. This is achieved by using a virtual IP address which is bound to the actual link address. During the roaming process the virtual address is attached to the new link address.

Some platforms may support the concept of Forced Roaming and Application Level Roaming (ALR). Forced roaming implies that the platform may simply roam to a new configuration without consulting applications. It is up to the application to detect the link layer loss and reestablish its sockets. In contrast ALR provides the opportunity to prevent the system from roaming. If this session is based on a configuration that supports roaming the application can choose whether it wants to be consulted (ALR use case) by connecting to this signal. For as long as this signal connection remains the session remains registered as a roaming stakeholder; otherwise roaming will be enforced by the platform.

See also

migrate(), ignore(), QNetworkConfiguration::isRoamingAvailable()

Referenced by connectNotify(), disconnectNotify(), QNetworkSession(), and QNetworkSessionPrivate::setPrivateConfiguration().

reject

void QNetworkSession::reject ( )

slot

The new access point is not suitable for the application.

By calling this function the session returns to the previous access point/configuration. This action may invalidate any socket that has been created via the not desired access point.

See also

accept()

Definition at line 643 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::setALREnabled().

{
    if (d)
        d->reject();
}

sessionProperty()

QVariant QNetworkSession::sessionProperty

(

const QString &

key

)

const

Returns the value for property key.

A network session can have properties attached which may describe the session in more details. This function can be used to gain access to those properties.

The following property keys are guaranteed to be specified on all platforms:

Key	Description
ActiveConfiguration	If the session isOpen() this property returns the identifier of the QNetworkConfiguration that is used by this session; otherwise an empty string. The main purpose of this key is to determine which Internet access point is used if the session is based on a ServiceNetwork. The following code snippet highlights the difference: QNetworkConfigurationManager mgr; QNetworkConfiguration ap = mgr.defaultConfiguration(); QNetworkSession *session = new QNetworkSession(ap); ... //code activates session QString ident = session->sessionProperty("ActiveConfiguration").toString(); if ( ap.type() == QNetworkConfiguration::ServiceNetwork ) { Q_ASSERT( ap.identifier() != ident ); Q_ASSERT( ap.children().contains( mgr.configurationFromIdentifier(ident) ) ); } else if ( ap.type() == QNetworkConfiguration::InternetAccessPoint ) { Q_ASSERT( ap.identifier() == ident ); }
UserChoiceConfiguration	If the session isOpen() and is bound to a QNetworkConfiguration of type UserChoice, this property returns the identifier of the QNetworkConfiguration that the configuration resolved to when open() was called; otherwise an empty string. The purpose of this key is to determine the real QNetworkConfiguration that the session is using. This key is different from ActiveConfiguration in that this key may return an identifier for either a QNetworkConfiguration::ServiceNetwork{service network} or a QNetworkConfiguration::InternetAccessPoint{Internet access points} configurations, whereas ActiveConfiguration always returns identifiers to QNetworkConfiguration::InternetAccessPoint{Internet access points} configurations.
ConnectInBackground	Setting this property to true before calling open() implies that the connection attempt is made but if no connection can be established, the user is not connsulted and asked to select a suitable connection. This property is not set by default and support for it depends on the platform.
AutoCloseSessionTimeout	If the session requires polling to keep its state up to date, this property holds the timeout in milliseconds before the session will automatically close. If the value of this property is -1 the session will not automatically close. This property is set to -1 by default. The purpose of this property is to minimize resource use on platforms that use polling to update the state of the session. Applications can set the value of this property to the desired timeout before the session is closed. In response to the closed() signal the network session should be deleted to ensure that all polling is stopped. The session can then be recreated once it is required again. This property has no effect for sessions that do not require polling.

Definition at line 553 of file qnetworksession.cpp.

Referenced by QNetworkAccessBackend::start(), and QNetworkSessionPrivate::~QNetworkSessionPrivate().

{
    if (!d || !d->publicConfig.isValid())
        return QVariant();

    if (key == QLatin1String("ActiveConfiguration"))
        return d->isOpen ? d->activeConfig.identifier() : QString();

    if (key == QLatin1String("UserChoiceConfiguration")) {
        if (!d->isOpen || d->publicConfig.type() != QNetworkConfiguration::UserChoice)
            return QString();

        if (d->serviceConfig.isValid())
            return d->serviceConfig.identifier();
        else
            return d->activeConfig.identifier();
    }

    return d->sessionProperty(key);
}

setSessionProperty()

void QNetworkSession::setSessionProperty	(	const QString &	key,
		const QVariant &	value
	)

Sets the property value on the session.

The property is identified using key. Removing an already set property can be achieved by passing an invalid QVariant.

Note that the UserChoiceConfiguration and ActiveConfiguration properties are read only and cannot be changed using this method.

Definition at line 582 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::~QNetworkSessionPrivate().

{
    if (!d)
        return;

    if (key == QLatin1String("ActiveConfiguration") ||
        key == QLatin1String("UserChoiceConfiguration")) {
        return;
    }

    d->setSessionProperty(key, value);
}

state()

QNetworkSession::State QNetworkSession::state

(

)

const

Returns the state of the session.

If the session is based on a single access point configuration the state of the session is the same as the state of the associated network interface. Therefore a network session object can be used to monitor network interfaces.

A QNetworkConfiguration::ServiceNetwork based session summarizes the state of all its children and therefore returns the Connected state if at least one of the service network's QNetworkConfiguration::children(){children()} configurations is active.

Note that it is not required to hold an open session in order to obtain the network interface state. A connected but closed session may be used to monitor network interfaces whereas an open and connected session object may prevent the network interface from being shut down.

See also

error(), stateChanged()

Definition at line 460 of file qnetworksession.cpp.

Referenced by QNetworkReplyImplPrivate::_q_networkSessionConnected(), and QNetworkSessionPrivate::setPrivateConfiguration().

{
    return d ? d->state : QNetworkSession::Invalid;
}

stateChanged

void QNetworkSession::stateChanged ( QNetworkSession::State  state )

signal

This signal is emitted whenever the state of the network session changes.

The state parameter is the new state.

See also

state()

Referenced by QNetworkSession(), and QNetworkSessionPrivate::setPrivateConfiguration().

stop

void QNetworkSession::stop ( )

slot

Invalidates all open sessions against the network interface and therefore stops the underlying network interface.

This function always changes the session's state() flag to Disconnected .

On Symbian platform, a 'NetworkControl' capability is required for full interface-level stop (without the capability, only the current session is stopped).

See also

open(), close()

Definition at line 397 of file qnetworksession.cpp.

Referenced by QNetworkSessionPrivate::~QNetworkSessionPrivate().

{
    if (d)
        d->stop();
}

waitForOpened()

bool QNetworkSession::waitForOpened

(

int

msecs = 30000

)

Waits until the session has been opened, up to msecs milliseconds.

If the session has been opened, this function returns true; otherwise it returns false. In the case where it returns false, you can call error() to determine the cause of the error.

The following example waits up to one second for the session to be opened:

session->open();
if (session->waitForOpened(1000))
    qDebug("Open!");

If msecs is -1, this function will not time out.

See also

open(), error()

Definition at line 341 of file qnetworksession.cpp.

{
    if (!d)
        return false;

    if (d->isOpen)
        return true;

    if (!(d->state == Connecting || d->state == Connected)) {
        return false;
    }

    QEventLoop loop;
    QObject::connect(d, SIGNAL(quitPendingWaitsForOpened()), &loop, SLOT(quit()));
    QObject::connect(this, SIGNAL(error(QNetworkSession::SessionError)), &loop, SLOT(quit()));

    //final call
    if (msecs >= 0)
        QTimer::singleShot(msecs, &loop, SLOT(quit()));

    // enter the event loop and wait for opened/error/timeout
    loop.exec(QEventLoop::ExcludeUserInputEvents | QEventLoop::WaitForMoreEvents);

    return d->isOpen;
}

Friends and Related Functions

QNetworkSessionPrivate

friend class QNetworkSessionPrivate

friend

Definition at line 139 of file qnetworksession.h.

Properties

d

QNetworkSessionPrivate* QNetworkSession::d

private

Definition at line 140 of file qnetworksession.h.

Referenced by accept(), activeTime(), bytesReceived(), bytesWritten(), close(), configuration(), connectNotify(), disconnectNotify(), error(), errorString(), ignore(), interface(), isOpen(), migrate(), open(), QNetworkSession(), reject(), sessionProperty(), setSessionProperty(), state(), stop(), waitForOpened(), and ~QNetworkSession().

---

The documentation for this class was generated from the following files:

• /src/network/bearer/qnetworksession.h
• /src/network/bearer/qnetworksession.cpp