QNetworkConfigurationManager Class

The QNetworkConfigurationManager class manages the network configurations provided by the system. More...

Header:	#include <QNetworkConfigurationManager>
qmake:	QT += network
Since:	Qt 4.7
Inherits:	QObject

This class was introduced in Qt 4.7.

• List of all members, including inherited members

Public Types

flags	Capabilities
enum	Capability { CanStartAndStopInterfaces, DirectConnectionRouting, SystemSessionSupport, ApplicationLevelRoaming, ForcedRoaming, …, NetworkSessionRequired }

Public Functions

	QNetworkConfigurationManager(QObject *parent = nullptr)
virtual	~QNetworkConfigurationManager()
QList<QNetworkConfiguration>	allConfigurations(QNetworkConfiguration::StateFlags filter = QNetworkConfiguration::StateFlags()) const
QNetworkConfigurationManager::Capabilities	capabilities() const
QNetworkConfiguration	configurationFromIdentifier(const QString &identifier) const
QNetworkConfiguration	defaultConfiguration() const
bool	isOnline() const

Public Slots

void	updateConfigurations()

Signals

void	configurationAdded(const QNetworkConfiguration &config)
void	configurationChanged(const QNetworkConfiguration &config)
void	configurationRemoved(const QNetworkConfiguration &config)
void	onlineStateChanged(bool isOnline)
void	updateCompleted()

Detailed Description

QNetworkConfigurationManager provides access to the network configurations known to the system and enables applications to detect the system capabilities (with regards to network sessions) at runtime.

A QNetworkConfiguration abstracts a set of configuration options describing how a network interface has to be configured to connect to a particular target network. QNetworkConfigurationManager maintains and updates the global list of QNetworkConfigurations. Applications can access and filter this list via allConfigurations(). If a new configuration is added or an existing one is removed or changed the configurationAdded(), configurationRemoved() and configurationChanged() signals are emitted respectively.

The defaultConfiguration() can be used when intending to immediately create a new network session without caring about the particular configuration. It returns a QNetworkConfiguration::Discovered configuration. If there are not any discovered ones an invalid configuration is returned.

Some configuration updates may require some time to perform updates. A WLAN scan is such an example. Unless the platform performs internal updates it may be required to manually trigger configuration updates via QNetworkConfigurationManager::updateConfigurations(). The completion of the update process is indicated by emitting the updateCompleted() signal. The update process ensures that every existing QNetworkConfiguration instance is updated. There is no need to ask for a renewed configuration list via allConfigurations().

See also QNetworkConfiguration.

Member Type Documentation

enum QNetworkConfigurationManager::Capabilityflags QNetworkConfigurationManager::Capabilities

Specifies the system capabilities of the bearer API. The possible values are:

Constant	Value	Description
QNetworkConfigurationManager::CanStartAndStopInterfaces	0x00000001	Network sessions and their underlying access points can be started and stopped. If this flag is not set QNetworkSession can only monitor but not influence the state of access points. On some platforms this feature may require elevated user permissions. This option is platform specific and may not always be available.
QNetworkConfigurationManager::DirectConnectionRouting	0x00000002	Network sessions and their sockets can be bound to a particular network interface. Any packet that passes through the socket goes to the specified network interface and thus disregards standard routing table entries. This may be useful when two interfaces can reach overlapping IP ranges or an application has specific needs in regards to target networks. This option is platform specific and may not always be available.
QNetworkConfigurationManager::SystemSessionSupport	0x00000004	If this flag is set the underlying platform ensures that a network interface is not shut down until the last network session has been closed(). This works across multiple processes. If the platform session support is missing this API can only ensure the above behavior for network sessions within the same process. In general mobile platforms have such support whereas most desktop platform lack this capability.
QNetworkConfigurationManager::ApplicationLevelRoaming	0x00000008	The system gives applications control over the systems roaming behavior. Applications can initiate roaming (in case the current link is not suitable) and are consulted if the system has identified a more suitable access point.
QNetworkConfigurationManager::ForcedRoaming	0x00000010	The system disconnects an existing access point and reconnects via a more suitable one. The application does not have any control over this process and has to reconnect its active sockets.
QNetworkConfigurationManager::DataStatistics	0x00000020	If this flag is set QNetworkSession can provide statistics about transmitted and received data.
QNetworkConfigurationManager::NetworkSessionRequired	0x00000040	If this flag is set the platform requires that a network session is created before network operations can be performed.

The Capabilities type is a typedef for QFlags<Capability>. It stores an OR combination of Capability values.

Member Function Documentation

QNetworkConfigurationManager::QNetworkConfigurationManager(QObject *parent = nullptr)

Constructs a QNetworkConfigurationManager with the given parent.

Note that to ensure a valid list of current configurations immediately available, updating is done during construction which causes some delay.

[signal] void QNetworkConfigurationManager::configurationAdded(const QNetworkConfiguration &config)

This signal is emitted whenever a new network configuration is added to the system. The new configuration is specified by config.

[signal] void QNetworkConfigurationManager::configurationChanged(const QNetworkConfiguration &config)

This signal is emitted when the state of config changes.

[signal] void QNetworkConfigurationManager::configurationRemoved(const QNetworkConfiguration &config)

This signal is emitted when a configuration is about to be removed from the system. The removed configuration, specified by config, is invalid but retains name and identifier.

[signal] void QNetworkConfigurationManager::onlineStateChanged(bool isOnline)

This signal is emitted when the device changes from online to offline mode or vice versa. isOnline represents the new state of the device.

The state is considered to be online for as long as allConfigurations(QNetworkConfiguration::Active) returns a list with at least one entry.

[signal] void QNetworkConfigurationManager::updateCompleted()

This signal is emitted when the configuration update has been completed. Such an update can be initiated via updateConfigurations().

[slot] void QNetworkConfigurationManager::updateConfigurations()

Initiates an update of all configurations. This may be used to initiate WLAN scans or other time consuming updates which may be required to obtain the correct state for configurations.

This call is asynchronous. On completion of this update the updateCompleted() signal is emitted. If new configurations are discovered or old ones were removed or changed the update process may trigger the emission of one or multiple configurationAdded(), configurationRemoved() and configurationChanged() signals.

If a configuration state changes as a result of this update all existing QNetworkConfiguration instances are updated automatically.

See also allConfigurations().

[virtual] QNetworkConfigurationManager::~QNetworkConfigurationManager()

Frees the resources associated with the QNetworkConfigurationManager object.

QList<QNetworkConfiguration> QNetworkConfigurationManager::allConfigurations(QNetworkConfiguration::StateFlags filter = QNetworkConfiguration::StateFlags()) const

Returns the list of configurations which comply with the given filter.

By default this function returns all (defined and undefined) configurations.

A wireless network with a particular SSID may only be accessible in a certain area despite the fact that the system has a valid configuration for it. Therefore the filter flag may be used to limit the list to discovered and possibly connected configurations only.

If filter is set to zero this function returns all possible configurations.

Note that this function returns the states for all configurations as they are known at the time of this function call. If for instance a configuration of type WLAN is defined the system may have to perform a WLAN scan in order to determine whether it is actually available. To obtain the most accurate state updateConfigurations() should be used to update each configuration's state. Note that such an update may require some time. It's completion is signalled by updateCompleted(). In the absence of a configuration update this function returns the best estimate at the time of the call. Therefore, if WLAN configurations are of interest, it is recommended that updateConfigurations() is called once after QNetworkConfigurationManager instantiation (WLAN scans are too time consuming to perform in constructor). After this the data is kept automatically up-to-date as the system reports any changes.

QNetworkConfigurationManager::Capabilities QNetworkConfigurationManager::capabilities() const

Returns the capabilities supported by the current platform.

QNetworkConfiguration QNetworkConfigurationManager::configurationFromIdentifier(const QString &identifier) const

Returns the QNetworkConfiguration for identifier; otherwise returns an invalid QNetworkConfiguration.

See also QNetworkConfiguration::identifier().

QNetworkConfiguration QNetworkConfigurationManager::defaultConfiguration() const

Returns the default configuration to be used. This function always returns a discovered configuration; otherwise an invalid configuration.

In some cases it may be required to call updateConfigurations() and wait for the updateCompleted() signal before calling this function.

See also allConfigurations().

bool QNetworkConfigurationManager::isOnline() const

Returns true if the system is considered to be connected to another device via an active network interface; otherwise returns false.

This is equivalent to the following code snippet:

QNetworkConfigurationManager mgr;
QList<QNetworkConfiguration> activeConfigs = mgr.allConfigurations(QNetworkConfiguration::Active);
if (activeConfigs.count() > 0)
    Q_ASSERT(mgr.isOnline());
else
    Q_ASSERT(!mgr.isOnline());

See also onlineStateChanged().