The SingleInstance class handles multiple instances. More...

#include <SingleInstance.h>

Inheritance diagram for SingleInstance:

Collaboration diagram for SingleInstance:

Public Types
enum	Mode { User = 1 << 0 , System = 1 << 1 , SecondaryNotification = 1 << 2 , ExcludeAppVersion = 1 << 3 , ExcludeAppPath = 1 << 4 }

Signals
void	instanceStarted ()

void	receivedMessage (quint32 instanceId, QByteArray message)

Public Member Functions
	SingleInstance (QObject *parent=nullptr)
	Default constructor.

	SingleInstance (bool allowSecondary, Options options=Mode::User, int timeout=1000, const QString &userData={}, QObject *parent=nullptr)
	Initializing constructor.

	~SingleInstance () override
	Destructor.

void	initialize (bool allowSecondary=false, Options options=Mode::User, int timeout=1000, const QString &userData={})
	Initializes this instance.

bool	isPrimary () const
	Gets if the instance is the primary instance.

bool	isSecondary () const
	Gets if the instance is a secondary instance.

quint32	instanceId () const
	Gets a unique identifier for the current instance.

qint64	primaryPid () const
	Gets the process ID (PID) of the primary instance.

QString	primaryUser () const
	Gets the username of the user running the primary instance.

QString	currentUser () const
	Gets the username of the current user.

bool	sendMessage (const QByteArray &message, int timeout=100)
	Sends a message to the primary instance. Returns true on success.

QStringList	userData () const
	Get the set user data.

Detailed Description

The SingleInstance class handles multiple instances.

Member Enumeration Documentation

◆ Mode

enum SingleInstance::Mode

Enumerator
User
System
SecondaryNotification
ExcludeAppVersion
ExcludeAppPath

Constructor & Destructor Documentation

◆ SingleInstance() [1/2]

SingleInstance::SingleInstance ( QObject * parent = nullptr )

explicit

Default constructor.

◆ SingleInstance() [2/2]

SingleInstance::SingleInstance	(	bool	allowSecondary,
		Options	options = `Mode::User`,
		int	timeout = `1000`,
		const QString &	userData = `{}`,
		QObject *	parent = `nullptr`
	)

explicit

Initializing constructor.

See also: initialize() for more.

◆ ~SingleInstance()

SingleInstance::~SingleInstance ( )

override

Destructor.

Member Function Documentation

◆ currentUser()

QString SingleInstance::currentUser ( ) const

Gets the username of the current user.

◆ initialize()

void SingleInstance::initialize	(	bool	allowSecondary = `false`,
		Options	options = `Mode::User`,
		int	timeout = `1000`,
		const QString &	userData = `{}`
	)

Initializes this instance.

Parameters

allowSecondary	Whether to start the instance as secondary if there is already a primary instance.
options	Whether for the SingleInstance block to be applied User wide or System wide.
timeout	Timeout to wait in milliseconds.
userData

Note: argc and argv may be changed as Qt removes arguments that it recognizes; Mode::SecondaryNotification only works if set on both the primary instance and the secondary instance.; The timeout is just a hint for the maximum time of blocking operations. It does not guarantee that the SingleInstance initialisation will be completed in given time, though is a good hint. Usually 4*timeout would be the worst case (fail) scenario.

◆ instanceId()

quint32 SingleInstance::instanceId ( ) const

Gets a unique identifier for the current instance.

◆ instanceStarted

void SingleInstance::instanceStarted ( )

signal

◆ isPrimary()

bool SingleInstance::isPrimary ( ) const

Gets if the instance is the primary instance.

◆ isSecondary()

bool SingleInstance::isSecondary ( ) const

Gets if the instance is a secondary instance.

◆ primaryPid()

qint64 SingleInstance::primaryPid ( ) const

Gets the process ID (PID) of the primary instance.

◆ primaryUser()

QString SingleInstance::primaryUser ( ) const

Gets the username of the user running the primary instance.

◆ receivedMessage

void SingleInstance::receivedMessage	(	quint32	instanceId,
		QByteArray	message
	)