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SystemSuspendHandler Class Reference
[QtBaseModule]

The SystemSuspendHandler class provides an interface for tasks that provide system suspension or resumption functionality. More...

    #include <SystemSuspendHandler>

Inherits QObject.

• List of all members, including inherited members

Public Functions

• SystemSuspendHandler ( QObject * parent = 0 )
• virtual bool canSuspend () const = 0
• virtual bool suspend () = 0
• virtual bool wake () = 0

• 29 public functions inherited from QObject

Signals

• void operationCompleted ()

• 1 signal inherited from QObject

Additional Inherited Members

• 1 property inherited from QObject
• 1 public slot inherited from QObject
• 1 public type inherited from QObject
• 4 static public members inherited from QObject
• 7 protected functions inherited from QObject
• 2 protected variables inherited from QObject

Detailed Description

The SystemSuspendHandler class provides an interface for tasks that provide system suspension or resumption functionality.

The SystemSuspendHandler provides a Qt Extended Server Task interface. Qt Extended Server Tasks are documented in full in the QtopiaServerApplication class documentation.

Server components can use the SystemSuspendHandler to integrate into the suspend mechanism.

Tasks that provide the SystemSuspendHandler interface will be called whenever a system suspend is requested through the SystemSuspend class. More information on how a system suspend proceeds, including the order in which SystemSuspendHandler implementers are called, is available in the documentation for that class.

This class is part of the Qt Extended server and cannot be used by other Qt Extended applications.

See also SystemSuspend.

Member Function Documentation

SystemSuspendHandler::SystemSuspendHandler ( QObject * parent = 0 )

Construct the handler with the given parent.

bool SystemSuspendHandler::canSuspend () const   [pure virtual]

Returns true if the handler is capable of suspending at the time it is called. Suspend handlers can return false from this call to prevent the system from entering a suspended state. This might be useful to prevent a suspend during a device synchronization or other scenarios where it may be advantageous not to enter such a state.

void SystemSuspendHandler::operationCompleted ()   [signal]

Emitted to indicate that the suspend or wake process can continue. This should only be emitted after previously returning false from suspend() or wake().

bool SystemSuspendHandler::suspend ()   [pure virtual]

Perform the handler's suspend action. If this method returns false, the suspend process will pause - entring the Qt event loop - until the handler emits the operationCompleted() signal. This can be used to perform asynchronous actions in the handler.

Normally this method will return true.

bool SystemSuspendHandler::wake ()   [pure virtual]

Perform the handler's wake action. If this method returns false, the wake process will pause - entering the Qt event loop - until the handler emits the operationCompleted() signal. This can be used to perform asynchronous actions in the handler.

Normally this method will return true.