Akonadi::AgentBase::Observer Class Reference

#include <agentbase.h>

Inheritance diagram for Akonadi::AgentBase::Observer:

Public Member Functions
	Observer ()
virtual	~Observer ()
virtual void	collectionAdded (const Akonadi::Collection &collection, const Akonadi::Collection &parent)
virtual void	collectionChanged (const Akonadi::Collection &collection)
virtual void	collectionRemoved (const Akonadi::Collection &collection)
virtual void	itemAdded (const Akonadi::Item &item, const Akonadi::Collection &collection)
virtual void	itemChanged (const Akonadi::Item &item, const QSet< QByteArray > &partIdentifiers)
virtual void	itemRemoved (const Akonadi::Item &item)

Detailed Description

The interface for reacting on monitored or replayed changes.

The Observer provides an interface to react on monitored or replayed changes.

Since the this base class does only tell the change recorder that the change has been processed, an AgentBase subclass which wants to actually process the change needs to subclass Observer and reimplement the methods it is interested in.

Such an agent specific Observer implementation can either be done stand-alone, i.e. as a separate object, or by inheriting both AgentBase and AgentBase::Observer.

The observer implementation then has registered with the agent, so it can forward the incoming changes to the observer.

Note

In the multiple inheritance approach the init() method automatically registers itself as the observer.

Do not call the base implementation of reimplemented virtual methods! The default implementation disconnected themselves from the Akonadi::ChangeRecorder to enable internal optimizations for unused notifications.

Example for stand-alone observer:

class ExampleAgent : public AgentBase
{
  public:
    ExampleAgent( const QString &id );
 
    ~ExampleAgent();
 
  private:
    AgentBase::Observer *mObserver;
};
 
class ExampleObserver : public AgentBase::Observer
{
  protected:
    void itemChanged( const Item &item );
};
 
ExampleAgent::ExampleAgent( const QString &id )
  : AgentBase( id )
  , mObserver( 0 )
{
  mObserver = new ExampleObserver();
  registerObserver( mObserver );
}
 
ExampleAgent::~ExampleAgent()
{
  delete mObserver;
}
 
void ExampleObserver::itemChanged( const Item &item )
{
  // do something with item
  qCDebug(AKONADIAGENTBASE_LOG) << "Item id=" << item.id();
 
  // let base implementation tell the change recorder that we
  // have processed the change
  AgentBase::Observer::itemChanged( item );
}

Example for observer through multiple inheritance:

class ExampleAgent : public AgentBase, public AgentBase::Observer
{
  public:
    ExampleAgent( const QString &id );
 
  protected:
    void itemChanged( const Item &item );
};
 
ExampleAgent::ExampleAgent( const QString &id )
  : AgentBase( id )
{
  // no need to create or register observer since
  // we are the observer and registration happens automatically
  // in init()
}
 
void ExampleAgent::itemChanged( const Item &item )
{
  // do something with item
  qCDebug(AKONADIAGENTBASE_LOG) << "Item id=" << item.id();
 
  // let base implementation tell the change recorder that we
  // have processed the change
  AgentBase::Observer::itemChanged( item );
}

Author

Kevin Krammer kevin.nosp@m..kra.nosp@m.mmer@.nosp@m.gmx..nosp@m.at

Deprecated

Use ObserverV2 instead

Definition at line 178 of file agentbase.h.

Constructor & Destructor Documentation

Observer()

AgentBase::Observer::Observer

(

)

Creates an observer instance.

Definition at line 57 of file agentbase.cpp.

~Observer()

AgentBase::Observer::~Observer ( )

virtual

Destroys the observer instance.

Definition at line 61 of file agentbase.cpp.

Member Function Documentation

collectionAdded()

void AgentBase::Observer::collectionAdded ( const Akonadi::Collection & collection, const Akonadi::Collection & parent )

virtual

Reimplement to handle adding of new collections.

Parameters

collection	The newly added collection.
parent	The parent collection.

Definition at line 91 of file agentbase.cpp.

collectionChanged()

void AgentBase::Observer::collectionChanged ( const Akonadi::Collection & collection )

virtual

Reimplement to handle changes to existing collections.

Parameters

collection

The changed collection.

Reimplemented in Akonadi::AgentBase::ObserverV2.

Definition at line 100 of file agentbase.cpp.

collectionRemoved()

void AgentBase::Observer::collectionRemoved ( const Akonadi::Collection & collection )

virtual

Reimplement to handle deletion of collections.

Parameters

collection

The deleted collection.

Definition at line 108 of file agentbase.cpp.

itemAdded()

void AgentBase::Observer::itemAdded ( const Akonadi::Item & item, const Akonadi::Collection & collection )

virtual

Reimplement to handle adding of new items.

Parameters

item	The newly added item.
collection	The collection item got added to.

Definition at line 65 of file agentbase.cpp.

itemChanged()

void AgentBase::Observer::itemChanged ( const Akonadi::Item & item, const QSet< QByteArray > & partIdentifiers )

virtual

Reimplement to handle changes to existing items.

Parameters

item	The changed item.
partIdentifiers	The identifiers of the item parts that has been changed.

Definition at line 74 of file agentbase.cpp.

itemRemoved()

void AgentBase::Observer::itemRemoved ( const Akonadi::Item & item )

virtual

Reimplement to handle deletion of items.

Parameters

item	The deleted item.

Definition at line 83 of file agentbase.cpp.

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The documentation for this class was generated from the following files:

• agentbase.h
• agentbase.cpp