Detailed Description

The wxFileSystemWatcher class allows to receive notifications of file system changes.

Note: Implementation limitations: this class is currently implemented for MSW, OS X and GTK ports but doesn't detect all changes correctly everywhere: under MSW accessing the file is not detected (only modifying it is) and under OS X neither accessing nor modifying is detected (only creating and deleting files is). Moreover, OS X version doesn't currently collapse pairs of create/delete events in a rename event, unlike the other ones.

For the full list of change types that are reported see wxFSWFlags.

This class notifies the application about the file system changes by sending events of wxFileSystemWatcherEvent class. By default these events are sent to the wxFileSystemWatcher object itself so you can derive from it and use the event table EVT_FSWATCHER macro to handle these events in a derived class method. Alternatively, you can use wxFileSystemWatcher::SetOwner() to send the events to another object. Or you could use wxEvtHandler::Connect() with wxEVT_FSWATCHER to handle these events in any other object. See the fswatcher sample for an example of the latter approach.

Library: wxBase

Category: File Handling

Since: 2.9.1

Public Member Functions
	wxFileSystemWatcher ()
	Default constructor.

virtual	~wxFileSystemWatcher ()
	Destructor.

virtual bool	Add (const wxFileName &path, int events=wxFSW_EVENT_ALL)
	Adds path to currently watched files.

virtual bool	AddTree (const wxFileName &path, int events=wxFSW_EVENT_ALL, const wxString &filter=wxEmptyString)
	This is the same as Add(), but also recursively adds every file/directory in the tree rooted at path.

virtual bool	Remove (const wxFileName &path)
	Removes path from the list of watched paths.

virtual bool	RemoveTree (const wxFileName &path)
	This is the same as Remove(), but also removes every file/directory belonging to the tree rooted at path.

virtual bool	RemoveAll ()
	Clears the list of currently watched paths.

int	GetWatchedPathsCount () const
	Returns the number of currently watched paths.

int	GetWatchedPaths (wxArrayString *paths) const
	Retrieves all watched paths and places them in paths.

void	SetOwner (wxEvtHandler *handler)
	Associates the file system watcher with the given handler object.

Public Member Functions inherited from wxEvtHandler
	wxEvtHandler ()
	Constructor.

virtual	~wxEvtHandler ()
	Destructor.

virtual void	QueueEvent (wxEvent *event)
	Queue event for a later processing.

virtual void	AddPendingEvent (const wxEvent &event)
	Post an event to be processed later.

template<typename T , typename T1 , ... >
void	CallAfter (void(T::*method)(T1,...), T1 x1,...)
	Asynchronously call the given method.

template<typename T >
void	CallAfter (const T &functor)
	Asynchronously call the given functor.

virtual bool	ProcessEvent (wxEvent &event)
	Processes an event, searching event tables and calling zero or more suitable event handler function(s).

bool	ProcessEventLocally (wxEvent &event)
	Try to process the event in this handler and all those chained to it.

bool	SafelyProcessEvent (wxEvent &event)
	Processes an event by calling ProcessEvent() and handles any exceptions that occur in the process.

void	ProcessPendingEvents ()
	Processes the pending events previously queued using QueueEvent() or AddPendingEvent(); you must call this function only if you are sure there are pending events for this handler, otherwise a `wxCHECK` will fail.

void	DeletePendingEvents ()
	Deletes all events queued on this event handler using QueueEvent() or AddPendingEvent().

virtual bool	SearchEventTable (wxEventTable &table, wxEvent &event)
	Searches the event table, executing an event handler function if an appropriate one is found.

void	Connect (int id, int lastId, wxEventType eventType, wxObjectEventFunction function, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	Connects the given function dynamically with the event handler, id and event type.

void	Connect (int id, wxEventType eventType, wxObjectEventFunction function, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	See the Connect(int, int, wxEventType, wxObjectEventFunction, wxObject, wxEvtHandler) overload for more info.

void	Connect (wxEventType eventType, wxObjectEventFunction function, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	See the Connect(int, int, wxEventType, wxObjectEventFunction, wxObject, wxEvtHandler) overload for more info.

bool	Disconnect (wxEventType eventType, wxObjectEventFunction function, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	Disconnects the given function dynamically from the event handler, using the specified parameters as search criteria and returning true if a matching function has been found and removed.

bool	Disconnect (int id=wxID_ANY, wxEventType eventType=wxEVT_NULL, wxObjectEventFunction function=NULL, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	See the Disconnect(wxEventType, wxObjectEventFunction, wxObject, wxEvtHandler) overload for more info.

bool	Disconnect (int id, int lastId, wxEventType eventType, wxObjectEventFunction function=NULL, wxObject userData=NULL, wxEvtHandler eventSink=NULL)
	See the Disconnect(wxEventType, wxObjectEventFunction, wxObject, wxEvtHandler) overload for more info.

template<typename EventTag , typename Functor >
void	Bind (const EventTag &eventType, Functor functor, int id=wxID_ANY, int lastId=wxID_ANY, wxObject *userData=NULL)
	Binds the given function, functor or method dynamically with the event.

template<typename EventTag , typename Class , typename EventArg , typename EventHandler >
void	Bind (const EventTag &eventType, void(Class::method)(EventArg &), EventHandler handler, int id=wxID_ANY, int lastId=wxID_ANY, wxObject *userData=NULL)
	See the Bind<>(const EventTag&, Functor, int, int, wxObject*) overload for more info.

template<typename EventTag , typename Functor >
bool	Unbind (const EventTag &eventType, Functor functor, int id=wxID_ANY, int lastId=wxID_ANY, wxObject *userData=NULL)
	Unbinds the given function, functor or method dynamically from the event handler, using the specified parameters as search criteria and returning true if a matching function has been found and removed.

template<typename EventTag , typename Class , typename EventArg , typename EventHandler >
bool	Unbind (const EventTag &eventType, void(Class::method)(EventArg &), EventHandler handler, int id=wxID_ANY, int lastId=wxID_ANY, wxObject *userData=NULL)
	See the Unbind<>(const EventTag&, Functor, int, int, wxObject*) overload for more info.

void *	GetClientData () const
	Returns user-supplied client data.

wxClientData *	GetClientObject () const
	Returns a pointer to the user-supplied client data object.

void	SetClientData (void *data)
	Sets user-supplied client data.

void	SetClientObject (wxClientData *data)
	Set the client data object.

bool	GetEvtHandlerEnabled () const
	Returns true if the event handler is enabled, false otherwise.

wxEvtHandler *	GetNextHandler () const
	Returns the pointer to the next handler in the chain.

wxEvtHandler *	GetPreviousHandler () const
	Returns the pointer to the previous handler in the chain.

void	SetEvtHandlerEnabled (bool enabled)
	Enables or disables the event handler.

virtual void	SetNextHandler (wxEvtHandler *handler)
	Sets the pointer to the next handler.

virtual void	SetPreviousHandler (wxEvtHandler *handler)
	Sets the pointer to the previous handler.

void	Unlink ()
	Unlinks this event handler from the chain it's part of (if any); then links the "previous" event handler to the "next" one (so that the chain won't be interrupted).

bool	IsUnlinked () const
	Returns true if the next and the previous handler pointers of this event handler instance are NULL.

Public Member Functions inherited from wxObject
	wxObject ()
	Default ctor; initializes to NULL the internal reference data.

	wxObject (const wxObject &other)
	Copy ctor.

virtual	~wxObject ()
	Destructor.

virtual wxClassInfo *	GetClassInfo () const
	This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar).

wxObjectRefData *	GetRefData () const
	Returns the wxObject::m_refData pointer, i.e. the data referenced by this object.

bool	IsKindOf (const wxClassInfo *info) const
	Determines whether this class is a subclass of (or the same class as) the given class.

bool	IsSameAs (const wxObject &obj) const
	Returns true if this object has the same data pointer as obj.

void	Ref (const wxObject &clone)
	Makes this object refer to the data in clone.

void	SetRefData (wxObjectRefData *data)
	Sets the wxObject::m_refData pointer.

void	UnRef ()
	Decrements the reference count in the associated data, and if it is zero, deletes the data.

void	UnShare ()
	This is the same of AllocExclusive() but this method is public.

void	operator delete (void *buf)
	The delete operator is defined for debugging versions of the library only, when the identifier `WXDEBUG` is defined.

void *	operator new (size_t size, const wxString &filename=NULL, int lineNum=0)
	The new operator is defined for debugging versions of the library only, when the identifier `WXDEBUG` is defined.

Additional Inherited Members
Static Public Member Functions inherited from wxEvtHandler
static void	AddFilter (wxEventFilter *filter)
	Add an event filter whose FilterEvent() method will be called for each and every event processed by wxWidgets.

static void	RemoveFilter (wxEventFilter *filter)
	Remove a filter previously installed with AddFilter().

Protected Member Functions inherited from wxEvtHandler
virtual bool	TryBefore (wxEvent &event)
	Method called by ProcessEvent() before examining this object event tables.

virtual bool	TryAfter (wxEvent &event)
	Method called by ProcessEvent() as last resort.

Protected Attributes inherited from wxObject
wxObjectRefData *	m_refData
	Pointer to an object which is the object's reference-counted data.

Constructor & Destructor Documentation

wxFileSystemWatcher::wxFileSystemWatcher ( )

Default constructor.

virtual wxFileSystemWatcher::~wxFileSystemWatcher ( )

virtual

Destructor.

Stops all paths from being watched and frees any system resources used by this file system watcher object.

Member Function Documentation

virtual bool wxFileSystemWatcher::Add	(	const wxFileName &	path,
		int	events = `wxFSW_EVENT_ALL`
	)

virtual

Adds path to currently watched files.

The path argument can currently only be a directory and any changes to this directory itself or its immediate children will generate the events. Use AddTree() to monitor the directory recursively.

Note that on platforms that use symbolic links, you should consider the possibility that path is a symlink. To watch the symlink itself and not its target you may call wxFileName::DontFollowLink() on path.

Parameters

path	The name of the path to watch.
events	An optional filter to receive only events of particular types. This is currently implemented only for GTK.

virtual bool wxFileSystemWatcher::AddTree	(	const wxFileName &	path,
		int	events = `wxFSW_EVENT_ALL`,
		const wxString &	filter = `wxEmptyString`
	)

virtual

This is the same as Add(), but also recursively adds every file/directory in the tree rooted at path.

Additionally a file mask can be specified to include only files matching that particular mask.

This method is implemented efficiently on MSW, but should be used with care on other platforms for directories with lots of children (e.g. the root directory) as it calls Add() for each subdirectory, potentially creating a lot of watches and taking a long time to execute.

Note that on platforms that use symbolic links, you will probably want to have called wxFileName::DontFollowLink on path. This is especially important if the symlink targets may themselves be watched.

int wxFileSystemWatcher::GetWatchedPaths ( wxArrayString * paths ) const

Retrieves all watched paths and places them in paths.

Returns the number of watched paths, which is also the number of entries added to paths.

int wxFileSystemWatcher::GetWatchedPathsCount ( ) const

Returns the number of currently watched paths.

See Also: GetWatchedPaths()

virtual bool wxFileSystemWatcher::Remove ( const wxFileName & path )

virtual

Removes path from the list of watched paths.

See the comment in Add() about symbolic links. path should treat symbolic links in the same way as in the original Add() call.

virtual bool wxFileSystemWatcher::RemoveAll ( )

virtual

Clears the list of currently watched paths.

virtual bool wxFileSystemWatcher::RemoveTree ( const wxFileName & path )

virtual

This is the same as Remove(), but also removes every file/directory belonging to the tree rooted at path.

See the comment in AddTree() about symbolic links. path should treat symbolic links in the same way as in the original AddTree() call.

void wxFileSystemWatcher::SetOwner ( wxEvtHandler * handler )

Associates the file system watcher with the given handler object.

All the events generated by this object will be passed to the specified owner.

Detailed Description

Public Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

Member Function Documentation