DirectoryContentsList Class Reference

A class to asynchronously scan for details about the files in a directory. More...

#include <juce_DirectoryContentsList.h>

Inheritance diagram for DirectoryContentsList:

Collaboration diagram for DirectoryContentsList:

Classes
struct	FileInfo
	Contains cached information about one of the files in a DirectoryContentsList. More...

Public Member Functions
	DirectoryContentsList (const FileFilter *fileFilter, TimeSliceThread &threadToUse)
	Creates a directory list. More...
	~DirectoryContentsList ()
	Destructor. More...
void	addChangeListener (ChangeListener *listener)
	Registers a listener to receive change callbacks from this broadcaster. More...
void	clear ()
	Clears the list, and stops the thread scanning for files. More...
bool	contains (const File &) const
	Returns true if the list contains the specified file. More...
void	dispatchPendingMessages ()
	If a change message has been sent but not yet dispatched, this will call sendSynchronousChangeMessage() to make the callback immediately. More...
const File &	getDirectory () const noexcept
	Returns the directory that's currently being used. More...
File	getFile (int index) const
	Returns one of the files in the list. More...
bool	getFileInfo (int index, FileInfo &resultInfo) const
	Returns the cached information about one of the files in the list. More...
const FileFilter *	getFilter () const noexcept
	Returns the file filter being used. More...
int	getNumFiles () const noexcept
	Returns the number of files currently available in the list. More...
TimeSliceThread &	getTimeSliceThread () const noexcept
bool	ignoresHiddenFiles () const
	Returns true if hidden files are ignored. More...
bool	isFindingDirectories () const noexcept
	Returns true if this list contains directories. More...
bool	isFindingFiles () const noexcept
	Returns true if this list contains files. More...
bool	isStillLoading () const
	True if the background thread hasn't yet finished scanning for files. More...
void	refresh ()
	Clears the list and restarts scanning the directory for files. More...
void	removeAllChangeListeners ()
	Removes all listeners from the list. More...
void	removeChangeListener (ChangeListener *listener)
	Unregisters a listener from the list. More...
void	sendChangeMessage ()
	Causes an asynchronous change message to be sent to all the registered listeners. More...
void	sendSynchronousChangeMessage ()
	Sends a synchronous change message to all the registered listeners. More...
void	setDirectory (const File &directory, bool includeDirectories, bool includeFiles)
	Sets the directory to look in for files. More...
void	setFileFilter (const FileFilter *newFileFilter)
	Replaces the current FileFilter. More...
void	setIgnoresHiddenFiles (bool shouldIgnoreHiddenFiles)
	Tells the list whether or not to ignore hidden files. More...

Private Member Functions
bool	addFile (const File &, bool isDir, int64 fileSize, Time modTime, Time creationTime, bool isReadOnly)
void	changed ()
bool	checkNextFile (bool &hasChanged)
void	setTypeFlags (int)
void	stopSearching ()
int	useTimeSlice () override
	Called back by a TimeSliceThread. More...

Private Attributes
const FileFilter *	fileFilter
ScopedPointer< DirectoryIterator >	fileFindHandle
CriticalSection	fileListLock
OwnedArray< FileInfo >	files
int	fileTypeFlags
File	root
bool volatile	shouldStop
TimeSliceThread &	thread

Detailed Description

A class to asynchronously scan for details about the files in a directory.

This keeps a list of files and some information about them, using a background thread to scan for more files. As files are found, it broadcasts change messages to tell any listeners.

See also

FileListComponent, FileBrowserComponent

Constructor & Destructor Documentation

DirectoryContentsList()

DirectoryContentsList::DirectoryContentsList	(	const FileFilter *	fileFilter,
		TimeSliceThread &	threadToUse
	)

Creates a directory list.

To set the directory it should point to, use setDirectory(), which will also start it scanning for files on the background thread.

When the background thread finds and adds new files to this list, the ChangeBroadcaster class will send a change message, so you can register listeners and update them when the list changes.

Parameters

fileFilter	an optional filter to select which files are included in the list. If this is nullptr, then all files and directories are included. Make sure that the filter doesn't get deleted during the lifetime of this object
threadToUse	a thread object that this list can use to scan for files as a background task. Make sure that the thread you give it has been started, or you won't get any files!

~DirectoryContentsList()

DirectoryContentsList::~DirectoryContentsList

(

)

Destructor.

Member Function Documentation

addChangeListener()

void ChangeBroadcaster::addChangeListener ( ChangeListener *  listener )

inherited

Registers a listener to receive change callbacks from this broadcaster.

Trying to add a listener that's already on the list will have no effect.

addFile()

bool DirectoryContentsList::addFile ( const File &  , bool  isDir, int64  fileSize, Time  modTime, Time  creationTime, bool  isReadOnly  )

private

changed()

void DirectoryContentsList::changed ( )

private

checkNextFile()

bool DirectoryContentsList::checkNextFile ( bool &  hasChanged )

private

clear()

void DirectoryContentsList::clear

(

)

Clears the list, and stops the thread scanning for files.

contains()

bool DirectoryContentsList::contains

(

const File &

)

const

Returns true if the list contains the specified file.

dispatchPendingMessages()

void ChangeBroadcaster::dispatchPendingMessages ( )

inherited

If a change message has been sent but not yet dispatched, this will call sendSynchronousChangeMessage() to make the callback immediately.

For thread-safety reasons, you must only call this method on the main message thread.

getDirectory()

const File& DirectoryContentsList::getDirectory ( ) const

inlinenoexcept

Returns the directory that's currently being used.

getFile()

File DirectoryContentsList::getFile

(

int

index

)

const

Returns one of the files in the list.

Parameters

index

should be less than getNumFiles(). If this is out-of-range, the return value will be a default File() object

See also

getNumFiles, getFileInfo

getFileInfo()

bool DirectoryContentsList::getFileInfo	(	int	index,
		FileInfo &	resultInfo
	)		const

Returns the cached information about one of the files in the list.

If the index is in-range, this will return true and will copy the file's details to the structure that is passed-in.

If it returns false, then the index wasn't in range, and the structure won't be affected.

See also

getNumFiles, getFile

getFilter()

const FileFilter* DirectoryContentsList::getFilter ( ) const

inlinenoexcept

Returns the file filter being used.

The filter is specified in the constructor.

getNumFiles()

int DirectoryContentsList::getNumFiles ( ) const

inlinenoexcept

Returns the number of files currently available in the list.

The info about one of these files can be retrieved with getFileInfo() or getFile().

Obviously as the background thread runs and scans the directory for files, this number will change.

See also

getFileInfo, getFile

getTimeSliceThread()

TimeSliceThread& DirectoryContentsList::getTimeSliceThread ( ) const

inlinenoexcept

ignoresHiddenFiles()

bool DirectoryContentsList::ignoresHiddenFiles

(

)

const

Returns true if hidden files are ignored.

See also

setIgnoresHiddenFiles

isFindingDirectories()

bool DirectoryContentsList::isFindingDirectories ( ) const

inlinenoexcept

Returns true if this list contains directories.

See also

setDirectory

References File::findDirectories.

isFindingFiles()

bool DirectoryContentsList::isFindingFiles ( ) const

inlinenoexcept

Returns true if this list contains files.

See also

setDirectory

References File::findFiles.

isStillLoading()

bool DirectoryContentsList::isStillLoading

(

)

const

True if the background thread hasn't yet finished scanning for files.

refresh()

void DirectoryContentsList::refresh

(

)

Clears the list and restarts scanning the directory for files.

removeAllChangeListeners()

void ChangeBroadcaster::removeAllChangeListeners ( )

inherited

Removes all listeners from the list.

removeChangeListener()

void ChangeBroadcaster::removeChangeListener ( ChangeListener *  listener )

inherited

Unregisters a listener from the list.

If the listener isn't on the list, this won't have any effect.

sendChangeMessage()

void ChangeBroadcaster::sendChangeMessage ( )

inherited

Causes an asynchronous change message to be sent to all the registered listeners.

The message will be delivered asynchronously by the main message thread, so this method will return immediately. To call the listeners synchronously use sendSynchronousChangeMessage().

Referenced by SelectedItemSet< SelectableItemType >::changed().

sendSynchronousChangeMessage()

void ChangeBroadcaster::sendSynchronousChangeMessage ( )

inherited

Sends a synchronous change message to all the registered listeners.

This will immediately call all the listeners that are registered. For thread-safety reasons, you must only call this method on the main message thread.

See also

dispatchPendingMessages

Referenced by SelectedItemSet< SelectableItemType >::changed().

setDirectory()

void DirectoryContentsList::setDirectory	(	const File &	directory,
		bool	includeDirectories,
		bool	includeFiles
	)

Sets the directory to look in for files.

If the directory that's passed in is different to the current one, this will also start the background thread scanning it for files.

setFileFilter()

void DirectoryContentsList::setFileFilter

(

const FileFilter *

newFileFilter

)

Replaces the current FileFilter.

This can be nullptr to have no filter. The DirectoryContentList does not take ownership of this object - it just keeps a pointer to it, so you must manage its lifetime. Note that this only replaces the filter, it doesn't refresh the list - you'll probably want to call refresh() after calling this.

setIgnoresHiddenFiles()

void DirectoryContentsList::setIgnoresHiddenFiles

(

bool

shouldIgnoreHiddenFiles

)

Tells the list whether or not to ignore hidden files.

By default these are ignored.

setTypeFlags()

void DirectoryContentsList::setTypeFlags ( int  )

private

stopSearching()

void DirectoryContentsList::stopSearching ( )

private

useTimeSlice()

int DirectoryContentsList::useTimeSlice ( )

overrideprivatevirtual

Called back by a TimeSliceThread.

When you register this class with it, a TimeSliceThread will repeatedly call this method.

The implementation of this method should use its time-slice to do something that's quick - never block for longer than absolutely necessary.

Returns

Your method should return the number of milliseconds which it would like to wait before being called again. Returning 0 will make the thread call again as soon as possible (after possibly servicing other busy clients). If you return a value below zero, your client will be removed from the list of clients, and won't be called again. The value you specify isn't a guaranteee, and is only used as a hint by the thread - the actual time before the next callback may be more or less than specified. You can force the TimeSliceThread to wake up and poll again immediately by calling its notify() method.

Implements TimeSliceClient.

Member Data Documentation

fileFilter

const FileFilter* DirectoryContentsList::fileFilter

private

fileFindHandle

ScopedPointer<DirectoryIterator> DirectoryContentsList::fileFindHandle

private

fileListLock

CriticalSection DirectoryContentsList::fileListLock

private

files

OwnedArray<FileInfo> DirectoryContentsList::files

private

fileTypeFlags

int DirectoryContentsList::fileTypeFlags

private

root

File DirectoryContentsList::root

private

shouldStop

bool volatile DirectoryContentsList::shouldStop

private

thread

TimeSliceThread& DirectoryContentsList::thread

private

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

• juce_DirectoryContentsList.h