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Move docs for QSessionManager to the right file.

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Change-Id: Ia3735ac14fe91de8cfbb58fc68f1a37f04d7b668
Reviewed-by: Gabriel de Dietrich <gabriel.dietrich-de@nokia.com>
This commit is contained in:
Frederik Gladhorn 2012-08-15 12:56:14 +02:00 committed by Qt by Nokia
parent 19276ac779
commit e0133de62f
2 changed files with 256 additions and 293 deletions
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247
src/gui/kernel/qsessionmanager.cpp
View File

@ -48,6 +48,81 @@
QT_BEGIN_NAMESPACE
/*!
\class QSessionManager
\brief The QSessionManager class provides access to the session manager.
\inmodule QtWidgets
A session manager in a desktop environment (in which Qt GUI applications
live) keeps track of a session, which is a group of running applications,
each of which has a particular state. The state of an application contains
(most notably) the documents the application has open and the position and
size of its windows.
The session manager is used to save the session, e.g., when the machine is
shut down, and to restore a session, e.g., when the machine is started up.
We recommend that you use QSettings to save an application's settings,
for example, window positions, recently used files, etc. When the
application is restarted by the session manager, you can restore the
settings.
QSessionManager provides an interface between the application and the
session manager so that the program can work well with the session manager.
In Qt, session management requests for action are handled by the two
virtual functions QApplication::commitData() and QApplication::saveState().
Both provide a reference to a session manager object as argument, to allow
the application to communicate with the session manager. The session
manager can only be accessed through these functions.
No user interaction is possible \e unless the application gets explicit
permission from the session manager. You ask for permission by calling
allowsInteraction() or, if it is really urgent, allowsErrorInteraction().
Qt does not enforce this, but the session manager may.
You can try to abort the shutdown process by calling cancel(). The default
commitData() function does this if some top-level window rejected its
closeEvent().
For sophisticated session managers provided on Unix/X11, QSessionManager
offers further possibilities to fine-tune an application's session
management behavior: setRestartCommand(), setDiscardCommand(),
setRestartHint(), setProperty(), requestPhase2(). See the respective
function descriptions for further details.
\sa QApplication, {Session Management}
*/
/*! \enum QSessionManager::RestartHint
This enum type defines the circumstances under which this application wants
to be restarted by the session manager. The current values are:
\value RestartIfRunning If the application is still running when the
session is shut down, it wants to be restarted
at the start of the next session.
\value RestartAnyway The application wants to be started at the
start of the next session, no matter what.
(This is useful for utilities that run just
after startup and then quit.)
\value RestartImmediately The application wants to be started immediately
whenever it is not running.
\value RestartNever The application does not want to be restarted
automatically.
The default hint is \c RestartIfRunning.
*/
/*!
\fn void* QSessionManager::handle() const
\internal
*/
class QSessionManagerPrivate : public QObjectPrivate
{
public:
@ -79,12 +154,32 @@ QSessionManager::~QSessionManager()
{
}
/*!
Returns the identifier of the current session.
If the application has been restored from an earlier session, this
identifier is the same as it was in the earlier session.
\sa sessionKey(), QApplication::sessionId()
*/
QString QSessionManager::sessionId() const
{
Q_D(const QSessionManager);
return d->sessionId;
}
/*!
\fn QString QSessionManager::sessionKey() const
Returns the session key in the current session.
If the application has been restored from an earlier session, this key is
the same as it was when the previous session ended.
The session key changes with every call of commitData() or saveState().
\sa sessionId(), QApplication::sessionKey()
*/
QString QSessionManager::sessionKey() const
{
Q_D(const QSessionManager);
@ -92,60 +187,184 @@ QString QSessionManager::sessionKey() const
}
/*!
Asks the session manager for permission to interact with the user. Returns
true if interaction is permitted; otherwise returns false.
The rationale behind this mechanism is to make it possible to synchronize
user interaction during a shutdown. Advanced session managers may ask all
applications simultaneously to commit their data, resulting in a much
faster shutdown.
When the interaction is completed we strongly recommend releasing the user
interaction semaphore with a call to release(). This way, other
applications may get the chance to interact with the user while your
application is still busy saving data. (The semaphore is implicitly
released when the application exits.)
If the user decides to cancel the shutdown process during the interaction
phase, you must tell the session manager that this has happened by calling
cancel().
Here's an example of how an application's QApplication::commitData() might
be implemented:
\snippet code/src_gui_kernel_qapplication.cpp 8
If an error occurred within the application while saving its data, you may
want to try allowsErrorInteraction() instead.
\sa QApplication::commitData(), release(), cancel()
*/
bool QSessionManager::allowsInteraction()
{
return false;
}
/*!
Returns true if error interaction is permitted; otherwise returns false.
This is similar to allowsInteraction(), but also enables the application to
tell the user about any errors that occur. Session managers may give error
interaction requests higher priority, which means that it is more likely
that an error interaction is permitted. However, you are still not
guaranteed that the session manager will allow interaction.
\sa allowsInteraction(), release(), cancel()
*/
bool QSessionManager::allowsErrorInteraction()
{
return false;
}
/*!
Releases the session manager's interaction semaphore after an interaction
phase.
\sa allowsInteraction(), allowsErrorInteraction()
*/
void QSessionManager::release()
{
}
/*!
Tells the session manager to cancel the shutdown process. Applications
should not call this function without asking the user first.
\sa allowsInteraction(), allowsErrorInteraction()
*/
void QSessionManager::cancel()
{
}
/*!
Sets the application's restart hint to \a hint. On application startup, the
hint is set to \c RestartIfRunning.
\note These flags are only hints, a session manager may or may not respect
them.
We recommend setting the restart hint in QApplication::saveState() because
most session managers perform a checkpoint shortly after an application's
startup.
\sa restartHint()
*/
void QSessionManager::setRestartHint(QSessionManager::RestartHint hint)
{
Q_D(QSessionManager);
d->restartHint = hint;
}
/*!
\fn QSessionManager::RestartHint QSessionManager::restartHint() const
Returns the application's current restart hint. The default is
\c RestartIfRunning.
\sa setRestartHint()
*/
QSessionManager::RestartHint QSessionManager::restartHint() const
{
Q_D(const QSessionManager);
return d->restartHint;
}
/*!
If the session manager is capable of restoring sessions it will execute
\a command in order to restore the application. The command defaults to
\snippet code/src_gui_kernel_qapplication.cpp 9
The \c -session option is mandatory; otherwise QApplication cannot tell
whether it has been restored or what the current session identifier is.
See QApplication::isSessionRestored() and QApplication::sessionId() for
details.
If your application is very simple, it may be possible to store the entire
application state in additional command line options. This is usually a
very bad idea because command lines are often limited to a few hundred
bytes. Instead, use QSettings, temporary files, or a database for this
purpose. By marking the data with the unique sessionId(), you will be able
to restore the application in a future session.
\sa restartCommand(), setDiscardCommand(), setRestartHint()
*/
void QSessionManager::setRestartCommand(const QStringList &command)
{
Q_D(QSessionManager);
d->restartCommand = command;
}
/*!
Returns the currently set restart command.
To iterate over the list, you can use the \l foreach pseudo-keyword:
\snippet code/src_gui_kernel_qapplication.cpp 10
\sa setRestartCommand(), restartHint()
*/
QStringList QSessionManager::restartCommand() const
{
Q_D(const QSessionManager);
return d->restartCommand;
}
/*!
Sets the discard command to the given \a list.
\sa discardCommand(), setRestartCommand()
*/
void QSessionManager::setDiscardCommand(const QStringList &command)
{
Q_D(QSessionManager);
d->discardCommand = command;
}
/*!
Returns the currently set discard command.
To iterate over the list, you can use the \l foreach pseudo-keyword:
\snippet code/src_gui_kernel_qapplication.cpp 11
\sa setDiscardCommand(), restartCommand(), setRestartCommand()
*/
QStringList QSessionManager::discardCommand() const
{
Q_D(const QSessionManager);
return d->discardCommand;
}
/*!
\overload
Low-level write access to the application's identification and state
records are kept in the session manager.
The property called \a name has its value set to the string \a value.
*/
void QSessionManager::setManagerProperty(const QString &name,
const QString &value)
{
@ -153,6 +372,12 @@ void QSessionManager::setManagerProperty(const QString &name,
Q_UNUSED(value);
}
/*!
Low-level write access to the application's identification and state record
are kept in the session manager.
The property called \a name has its value set to the string list \a value.
*/
void QSessionManager::setManagerProperty(const QString &name,
const QStringList &value)
{
@ -160,11 +385,33 @@ void QSessionManager::setManagerProperty(const QString &name,
Q_UNUSED(value);
}
/*!
Returns true if the session manager is currently performing a second
session management phase; otherwise returns false.
\sa requestPhase2()
*/
bool QSessionManager::isPhase2() const
{
return false;
}
/*!
Requests a second session management phase for the application. The
application may then return immediately from the QApplication::commitData()
or QApplication::saveState() function, and they will be called again once
most or all other applications have finished their session management.
The two phases are useful for applications such as the X11 window manager
that need to store information about another application's windows and
therefore have to wait until these applications have completed their
respective session management tasks.
\note If another application has requested a second phase it may get called
before, simultaneously with, or after your application's second phase.
\sa isPhase2()
*/
void QSessionManager::requestPhase2()
{
}

302
src/widgets/kernel/qapplication.cpp
View File

@ -3595,298 +3595,6 @@ bool QApplicationPrivate::notify_helper(QObject *receiver, QEvent * e)
}
/*!
\class QSessionManager
\brief The QSessionManager class provides access to the session manager.
\inmodule QtWidgets
A session manager in a desktop environment (in which Qt GUI applications
live) keeps track of a session, which is a group of running applications,
each of which has a particular state. The state of an application contains
(most notably) the documents the application has open and the position and
size of its windows.
The session manager is used to save the session, e.g., when the machine is
shut down, and to restore a session, e.g., when the machine is started up.
We recommend that you use QSettings to save an application's settings,
for example, window positions, recently used files, etc. When the
application is restarted by the session manager, you can restore the
settings.
QSessionManager provides an interface between the application and the
session manager so that the program can work well with the session manager.
In Qt, session management requests for action are handled by the two
virtual functions QApplication::commitData() and QApplication::saveState().
Both provide a reference to a session manager object as argument, to allow
the application to communicate with the session manager. The session
manager can only be accessed through these functions.
No user interaction is possible \e unless the application gets explicit
permission from the session manager. You ask for permission by calling
allowsInteraction() or, if it is really urgent, allowsErrorInteraction().
Qt does not enforce this, but the session manager may.
You can try to abort the shutdown process by calling cancel(). The default
commitData() function does this if some top-level window rejected its
closeEvent().
For sophisticated session managers provided on Unix/X11, QSessionManager
offers further possibilities to fine-tune an application's session
management behavior: setRestartCommand(), setDiscardCommand(),
setRestartHint(), setProperty(), requestPhase2(). See the respective
function descriptions for further details.
\sa QApplication, {Session Management}
*/
/*! \enum QSessionManager::RestartHint
This enum type defines the circumstances under which this application wants
to be restarted by the session manager. The current values are:
\value RestartIfRunning If the application is still running when the
session is shut down, it wants to be restarted
at the start of the next session.
\value RestartAnyway The application wants to be started at the
start of the next session, no matter what.
(This is useful for utilities that run just
after startup and then quit.)
\value RestartImmediately The application wants to be started immediately
whenever it is not running.
\value RestartNever The application does not want to be restarted
automatically.
The default hint is \c RestartIfRunning.
*/
/*!
\fn QString QSessionManager::sessionId() const
Returns the identifier of the current session.
If the application has been restored from an earlier session, this
identifier is the same as it was in the earlier session.
\sa sessionKey(), QApplication::sessionId()
*/
/*!
\fn QString QSessionManager::sessionKey() const
Returns the session key in the current session.
If the application has been restored from an earlier session, this key is
the same as it was when the previous session ended.
The session key changes with every call of commitData() or saveState().
\sa sessionId(), QApplication::sessionKey()
*/
/*!
\fn void* QSessionManager::handle() const
\internal
*/
/*!
\fn bool QSessionManager::allowsInteraction()
Asks the session manager for permission to interact with the user. Returns
true if interaction is permitted; otherwise returns false.
The rationale behind this mechanism is to make it possible to synchronize
user interaction during a shutdown. Advanced session managers may ask all
applications simultaneously to commit their data, resulting in a much
faster shutdown.
When the interaction is completed we strongly recommend releasing the user
interaction semaphore with a call to release(). This way, other
applications may get the chance to interact with the user while your
application is still busy saving data. (The semaphore is implicitly
released when the application exits.)
If the user decides to cancel the shutdown process during the interaction
phase, you must tell the session manager that this has happened by calling
cancel().
Here's an example of how an application's QApplication::commitData() might
be implemented:
\snippet code/src_gui_kernel_qapplication.cpp 8
If an error occurred within the application while saving its data, you may
want to try allowsErrorInteraction() instead.
\sa QApplication::commitData(), release(), cancel()
*/
/*!
\fn bool QSessionManager::allowsErrorInteraction()
Returns true if error interaction is permitted; otherwise returns false.
This is similar to allowsInteraction(), but also enables the application to
tell the user about any errors that occur. Session managers may give error
interaction requests higher priority, which means that it is more likely
that an error interaction is permitted. However, you are still not
guaranteed that the session manager will allow interaction.
\sa allowsInteraction(), release(), cancel()
*/
/*!
\fn void QSessionManager::release()
Releases the session manager's interaction semaphore after an interaction
phase.
\sa allowsInteraction(), allowsErrorInteraction()
*/
/*!
\fn void QSessionManager::cancel()
Tells the session manager to cancel the shutdown process. Applications
should not call this function without asking the user first.
\sa allowsInteraction(), allowsErrorInteraction()
*/
/*!
\fn void QSessionManager::setRestartHint(RestartHint hint)
Sets the application's restart hint to \a hint. On application startup, the
hint is set to \c RestartIfRunning.
\note These flags are only hints, a session manager may or may not respect
them.
We recommend setting the restart hint in QApplication::saveState() because
most session managers perform a checkpoint shortly after an application's
startup.
\sa restartHint()
*/
/*!
\fn QSessionManager::RestartHint QSessionManager::restartHint() const
Returns the application's current restart hint. The default is
\c RestartIfRunning.
\sa setRestartHint()
*/
/*!
\fn void QSessionManager::setRestartCommand(const QStringList& command)
If the session manager is capable of restoring sessions it will execute
\a command in order to restore the application. The command defaults to
\snippet code/src_gui_kernel_qapplication.cpp 9
The \c -session option is mandatory; otherwise QApplication cannot tell
whether it has been restored or what the current session identifier is.
See QApplication::isSessionRestored() and QApplication::sessionId() for
details.
If your application is very simple, it may be possible to store the entire
application state in additional command line options. This is usually a
very bad idea because command lines are often limited to a few hundred
bytes. Instead, use QSettings, temporary files, or a database for this
purpose. By marking the data with the unique sessionId(), you will be able
to restore the application in a future session.
\sa restartCommand(), setDiscardCommand(), setRestartHint()
*/
/*!
\fn QStringList QSessionManager::restartCommand() const
Returns the currently set restart command.
To iterate over the list, you can use the \l foreach pseudo-keyword:
\snippet code/src_gui_kernel_qapplication.cpp 10
\sa setRestartCommand(), restartHint()
*/
/*!
\fn void QSessionManager::setDiscardCommand(const QStringList& list)
Sets the discard command to the given \a list.
\sa discardCommand(), setRestartCommand()
*/
/*!
\fn QStringList QSessionManager::discardCommand() const
Returns the currently set discard command.
To iterate over the list, you can use the \l foreach pseudo-keyword:
\snippet code/src_gui_kernel_qapplication.cpp 11
\sa setDiscardCommand(), restartCommand(), setRestartCommand()
*/
/*!
\fn void QSessionManager::setManagerProperty(const QString &name, const QString &value)
\overload
Low-level write access to the application's identification and state
records are kept in the session manager.
The property called \a name has its value set to the string \a value.
*/
/*!
\fn void QSessionManager::setManagerProperty(const QString& name,
const QStringList& value)
Low-level write access to the application's identification and state record
are kept in the session manager.
The property called \a name has its value set to the string list \a value.
*/
/*!
\fn bool QSessionManager::isPhase2() const
Returns true if the session manager is currently performing a second
session management phase; otherwise returns false.
\sa requestPhase2()
*/
/*!
\fn void QSessionManager::requestPhase2()
Requests a second session management phase for the application. The
application may then return immediately from the QApplication::commitData()
or QApplication::saveState() function, and they will be called again once
most or all other applications have finished their session management.
The two phases are useful for applications such as the X11 window manager
that need to store information about another application's windows and
therefore have to wait until these applications have completed their
respective session management tasks.
\note If another application has requested a second phase it may get called
before, simultaneously with, or after your application's second phase.
\sa isPhase2()
*/
/*!
\fn Qt::MacintoshVersion QApplication::macVersion()
@ -4110,7 +3818,6 @@ int QApplication::cursorFlashTime()
return qApp->styleHints()->cursorFlashTime();
}
/*!
\property QApplication::doubleClickInterval
\brief the time limit in milliseconds that distinguishes a double click
@ -4131,6 +3838,15 @@ int QApplication::doubleClickInterval()
return qApp->styleHints()->mouseDoubleClickInterval();
}
/*!
\fn QGuiApplication::keyboardInputDirection()
\since 4.2
\deprecated
Returns the current keyboard input direction. Replaced with QInputPanel::inputDirection()
\sa QInputPanel::inputDirection()
*/
/*!
\property QApplication::keyboardInputInterval
\brief the time limit in milliseconds that distinguishes a key press