QSystemTrayIcon Class Reference

The QSystemTrayIcon class provides an icon for an application in the system tray. More...

 #include <QSystemTrayIcon>

Inherits: QObject.

This class was introduced in Qt 4.2.

Public Types

enum ActivationReason { Unknown, Context, DoubleClick, Trigger, MiddleClick }
enum MessageIcon { NoIcon, Information, Warning, Critical }

Properties

Public Functions

QSystemTrayIcon ( QObject * parent = 0 )
QSystemTrayIcon ( const QIcon & icon, QObject * parent = 0 )
~QSystemTrayIcon ()
QMenu * contextMenu () const
QRect geometry () const
QIcon icon () const
bool isVisible () const
void setContextMenu ( QMenu * menu )
void setIcon ( const QIcon & icon )
void setToolTip ( const QString & tip )
void showMessage ( const QString & title, const QString & message, MessageIcon icon = Information, int millisecondsTimeoutHint = 10000 )
QString toolTip () const
  • 29 public functions inherited from QObject

Public Slots

void hide ()
void setVisible ( bool visible )
void show ()
  • 1 public slot inherited from QObject

Signals

void activated ( QSystemTrayIcon::ActivationReason reason )
void messageClicked ()

Static Public Members

bool isSystemTrayAvailable ()
bool supportsMessages ()
  • 7 static public members inherited from QObject

Reimplemented Protected Functions

virtual bool event ( QEvent * e )
  • 8 protected functions inherited from QObject

Detailed Description

The QSystemTrayIcon class provides an icon for an application in the system tray.

Modern operating systems usually provide a special area on the desktop, called the system tray or notification area, where long-running applications can display icons and short messages.

The system tray on Windows XP.

The QSystemTrayIcon class can be used on the following platforms:

  • All supported versions of Windows.
  • All window managers for X11 that implement the freedesktop.org system tray specification, including recent versions of KDE and GNOME.
  • All supported versions of Mac OS X. Note that the Growl notification system must be installed for QSystemTrayIcon::showMessage() to display messages.

To check whether a system tray is present on the user's desktop, call the QSystemTrayIcon::isSystemTrayAvailable() static function.

To add a system tray entry, create a QSystemTrayIcon object, call setContextMenu() to provide a context menu for the icon, and call show() to make it visible in the system tray. Status notification messages ("balloon messages") can be displayed at any time using showMessage().

If the system tray is unavailable when a system tray icon is constructed, but becomes available later, QSystemTrayIcon will automatically add an entry for the application in the system tray if the icon is visible.

The activated() signal is emitted when the user activates the icon.

Only on X11, when a tooltip is requested, the QSystemTrayIcon receives a QHelpEvent of type QEvent::ToolTip. Additionally, the QSystemTrayIcon receives wheel events of type QEvent::Wheel. These are not supported on any other platform.

See also QDesktopServices, QDesktopWidget, Desktop Integration, and System Tray Icon Example.

Member Type Documentation

enum QSystemTrayIcon::ActivationReason

This enum describes the reason the system tray was activated.

ConstantValueDescription
QSystemTrayIcon::Unknown0Unknown reason
QSystemTrayIcon::Context1The context menu for the system tray entry was requested
QSystemTrayIcon::DoubleClick2The system tray entry was double clicked
QSystemTrayIcon::Trigger3The system tray entry was clicked
QSystemTrayIcon::MiddleClick4The system tray entry was clicked with the middle mouse button

See also activated().

enum QSystemTrayIcon::MessageIcon

This enum describes the icon that is shown when a balloon message is displayed.

ConstantValueDescription
QSystemTrayIcon::NoIcon0No icon is shown.
QSystemTrayIcon::Information1An information icon is shown.
QSystemTrayIcon::Warning2A standard warning icon is shown.
QSystemTrayIcon::Critical3A critical warning icon is shown.

See also QMessageBox.

Property Documentation

icon : QIcon

This property holds the system tray icon.

On Windows, the system tray icon size is 16x16; on X11, the preferred size is 22x22. The icon will be scaled to the appropriate size as necessary.

Access functions:

QIcon icon () const
void setIcon ( const QIcon & icon )

toolTip : QString

This property holds the tooltip for the system tray entry.

On some systems, the tooltip's length is limited. The tooltip will be truncated if necessary.

Access functions:

QString toolTip () const
void setToolTip ( const QString & tip )

visible : bool

This property holds whether the system tray entry is visible.

Setting this property to true or calling show() makes the system tray icon visible; setting this property to false or calling hide() hides it.

Access functions:

bool isVisible () const
void setVisible ( bool visible )

Member Function Documentation

QSystemTrayIcon::QSystemTrayIcon ( QObject * parent = 0 )

Constructs a QSystemTrayIcon object with the given parent.

The icon is initially invisible.

See also visible.

QSystemTrayIcon::QSystemTrayIcon ( const QIcon & icon, QObject * parent = 0 )

Constructs a QSystemTrayIcon object with the given icon and parent.

The icon is initially invisible.

See also visible.

QSystemTrayIcon::~QSystemTrayIcon ()

Removes the icon from the system tray and frees all allocated resources.

void QSystemTrayIcon::activated ( QSystemTrayIcon::ActivationReason reason ) [signal]

This signal is emitted when the user activates the system tray icon. reason specifies the reason for activation. QSystemTrayIcon::ActivationReason enumerates the various reasons.

See also QSystemTrayIcon::ActivationReason.

QMenu * QSystemTrayIcon::contextMenu () const

Returns the current context menu for the system tray entry.

See also setContextMenu().

bool QSystemTrayIcon::event ( QEvent * e ) [virtual protected]

Reimplemented from QObject::event().

QRect QSystemTrayIcon::geometry () const

Returns the geometry of the system tray icon in screen coordinates.

This function was introduced in Qt 4.3.

See also visible.

void QSystemTrayIcon::hide () [slot]

Hides the system tray entry.

See also show() and visible.

bool QSystemTrayIcon::isSystemTrayAvailable () [static]

Returns true if the system tray is available; otherwise returns false.

If the system tray is currently unavailable but becomes available later, QSystemTrayIcon will automatically add an entry in the system tray if it is visible.

void QSystemTrayIcon::messageClicked () [signal]

This signal is emitted when the message displayed using showMessage() was clicked by the user.

Currently this signal is not sent on Mac OS X.

Note: We follow Microsoft Windows XP/Vista behavior, so the signal is also emitted when the user clicks on a tray icon with a balloon message displayed.

See also activated().

void QSystemTrayIcon::setContextMenu ( QMenu * menu )

Sets the specified menu to be the context menu for the system tray icon.

The menu will pop up when the user requests the context menu for the system tray icon by clicking the mouse button.

On Mac OS X, this is currenly converted to a NSMenu, so the aboutToHide() signal is not emitted.

Note: The system tray icon does not take ownership of the menu. You must ensure that it is deleted at the appropriate time by, for example, creating the menu with a suitable parent object.

See also contextMenu().

void QSystemTrayIcon::show () [slot]

Shows the icon in the system tray.

See also hide() and visible.

void QSystemTrayIcon::showMessage ( const QString & title, const QString & message, MessageIcon icon = Information, int millisecondsTimeoutHint = 10000 )

Shows a balloon message for the entry with the given title, message and icon for the time specified in millisecondsTimeoutHint. title and message must be plain text strings.

Message can be clicked by the user; the messageClicked() signal will emitted when this occurs.

Note that display of messages are dependent on the system configuration and user preferences, and that messages may not appear at all. Hence, it should not be relied upon as the sole means for providing critical information.

On Windows, the millisecondsTimeoutHint is usually ignored by the system when the application has focus.

On Mac OS X, the Growl notification system must be installed for this function to display messages.

This function was introduced in Qt 4.3.

See also show() and supportsMessages().

bool QSystemTrayIcon::supportsMessages () [static]

Returns true if the system tray supports balloon messages; otherwise returns false.

See also showMessage().

Notes provided by the Qt Community
Cool Hack
  • 5

Votes: 4

Coverage: Qt library 4.7, 4.8, 5.0

Picture of Volker Volker

Ant Farmer
35 notes

Nokia Certified Qt Developer

Hide a tray icon in a slot connected to a signal

If you want to hide the system tray icon in a slot connected to a signal (eg. activated()), the application will crash on Mac OS X if you do it the straight forward way like this one:

  1. void MyClass::trayIconActivated()
  2. {
  3.     trayIcon->hide();
  4. }

It’s most likely caused by some internal objects that are deleted upon hide but which are needed until the signal/slot connections are processed.

You can work around this by using a single shot timer:

  1. void MyClass::trayIconActivated()
  2. {
  3.     QTimer::singleShot(0, trayIcon, SLOT(hide()));
  4. }

This way slot hide() is only called after the signal/slot connections have been processed.

[Revisions]

Cool Hack
  • 5

Votes: 2

Coverage: Qt library 4.7, 4.8, 5.0

Picture of tucnak tucnak

Ant Farmer
9 notes

Unity Desktop

On Ubuntu Linux from version 11.04 Ubuntu use Unity Desktop. In defaults it forbid applications to create their own tray icons in the tray.

To fix it, people are running special command throught installation and configuration of Unity. But if you are creating software specialised on Unity it will be klever to do it customly:

  1. gsettings get com.canonical.Unity.Panel systray-whitelist // will print allowed applications in JSON list
  2. gsettings set com.canonical.Unity.Panel systray-whitelist <whitelist> // set whitelist

Example if current list [“Dropbox”, “Foo”] – and we want to add “Bar” application:

  1. gsettings set com.canonical.Unity.Panel systray-whitelist "['Dropbox', 'Foo', 'Bar']"

And restart application.

I think it will be useful for Ubuntu-developers.

[Revisions]

Best Practice
  • 4

Votes: 1

Coverage: Qt library 4.8

Picture of francomartins francomartins

Lab Rat
9 notes

Example of use the SystemTrayIcon

Simples Evento de minimizar , maximizar e fechar um applicativo (Simple event to minimize, maximize and close an application)

  1. QMenu *trayIconMenu;
  2.    QAction *minimizeAction;
  3.    QAction *restoreAction;
  4.    QAction *quitAction;
  5.    minimizeAction = new QAction("Minimizar", this);
  6.    restoreAction = new QAction("Restaurar", this);
  7.    quitAction = new QAction("Sair", this);
  8.  
  9.    connect (minimizeAction, SIGNAL(triggered()), this, SLOT(hide()));
  10.    connect (restoreAction, SIGNAL(triggered()),this,SLOT(showNormal()));
  11.    connect (quitAction, SIGNAL(triggered()), qApp, SLOT(quit()));
  12.    trayIconMenu = new QMenu(this);
  13.    trayIconMenu->addAction (minimizeAction);
  14.    trayIconMenu->addAction (restoreAction);
  15.    trayIconMenu->addAction (quitAction);
  16.    QSystemTrayIcon* systray = new QSystemTrayIcon(this);
  17.    QIcon icon(":/ok.png"); // add a file ok.png in resource file
  18.    systray->setIcon(icon);
  19.    systray->setContextMenu (trayIconMenu);
  20.    systray->show();

[Revisions]