kio Library API Documentation

KFileMetaInfo Class Reference

This is the class for objects that hold meta information about a file.Meta Information about a file. More...

#include <kfilemetainfo.h>

List of all members.

Public Types

typedef KFileMimeTypeInfo::Hint Hint
typedef KFileMimeTypeInfo::Unit Unit
typedef KFileMimeTypeInfo::Attributes Attributes
enum  What {
  Fastest = 0x1, DontCare = 0x2, TechnicalInfo = 0x4, ContentInfo = 0x8,
  ExtenedAttr = 0x10, Thumbnail = 0x20, Preferred = 0x40, Everything = 0xffff
}

Public Member Functions

 KFileMetaInfo (const QString &path, const QString &mimeType=QString::null, uint what=Fastest)
 KFileMetaInfo (const KURL &url, const QString &mimeType=QString::null, uint what=Fastest)
 KFileMetaInfo ()
 KFileMetaInfo (const KFileMetaInfo &original)
const KFileMetaInfooperator= (const KFileMetaInfo &info)
QStringList groups () const
QStringList supportedGroups () const
QStringList preferredGroups () const
QStringList preferredKeys () const
QStringList supportedKeys () const
QStringList editableGroups () const
KFileMetaInfoItem item (const QString &key) const
KFileMetaInfoItem item (const KFileMetaInfoItem::Hint hint) const
KFileMetaInfoItem saveItem (const QString &key, const QString &preferredGroup=QString::null, bool createGroup=true)
KFileMetaInfoGroup group (const QString &key) const
KFileMetaInfoGroup operator[] (const QString &key) const
bool addGroup (const QString &name)
bool removeGroup (const QString &name)
QStringList removedGroups ()
bool applyChanges ()
bool contains (const QString &key) const
bool containsGroup (const QString &key) const
const QVariant value (const QString &key) const
bool isValid () const
bool isEmpty () const
QString mimeType () const
QString path () const
KURL url () const

Protected Member Functions

KFileMetaInfoGroup appendGroup (const QString &name)
KFilePlugin *const plugin () const
void ref ()
void deref ()

Protected Attributes

Data * d

Friends

class KFilePlugin
KIO_EXPORT friend QDataStreamoperator>> (QDataStream &s, KFileMetaInfo &)
KIO_EXPORT friend QDataStreamoperator<< (QDataStream &s, const KFileMetaInfo &)


Detailed Description

This is the class for objects that hold meta information about a file.Meta Information about a file.

The information is kept in form of a system of key/value pairs. See also KFileMetaInfoItem. This information is retrieved from the file through a plugin system, and this class is the main interface to it. If you want to write your own plugin, have a look at KFilePlugin. There are basically two different kinds of meta information: Fixed ones that the plugin knows about (e.g. an mp3 id3v1 tag has a well defined fixed list of fields), and variable keys that exist in mimetypes that support their own key/value system (comments in png files are of this type). Almost every file has fixed keys, but some also have variable keys.

The groups and the What enum are not yet supported, but already added to the interface so that adding support doesn't break compatibility.

Definition at line 887 of file kfilemetainfo.h.


Member Enumeration Documentation

enum KFileMetaInfo::What
 

This is used to specify what a KFileMetaInfo object should read, so you can specify if you want to read "expensive" items or not.

Enumeration values:
Fastest  do the fastest possible read and omit all items that might need a significantly longer time than the others
DontCare  let the plugin decide what to read
TechnicalInfo  extract technical details about the file, like e.g.

play time, resolution or a compressioni type

ContentInfo  read information about the content of the file, like comments or id3 tags
ExtenedAttr  read filesystem based extended attributes if they are supported for the filesystem
Thumbnail  only read the file's thumbnail, if it contains one
Preferred  get at least the preferred items
Everything  read everything, even if it might take a while

Definition at line 899 of file kfilemetainfo.h.


Constructor & Destructor Documentation

KFileMetaInfo::KFileMetaInfo const QString path,
const QString mimeType = QString::null,
uint  what = Fastest
 

The constructor.

creating a KFileMetaInfo item through this will autoload the plugin belonging to the mimetype and try to get meta information about the specified file.

If no info is available, you'll get an empty (not invalid) object. You can test for it with the isEmpty() method.

Parameters:
path The file name. This must be the path to a local file.
mimeType The name of the file's mimetype. If ommited, the mimetype is autodetected
what one or more of the What enum values. It gives some hint to the plugin what information is desired. The plugin may still return more items.
Note:
This version will only work for local (file:/) files.

Definition at line 297 of file kfilemetainfo.cpp.

References KURL::setPath().

KFileMetaInfo::KFileMetaInfo const KURL url,
const QString mimeType = QString::null,
uint  what = Fastest
 

Another constructor.

Similar to the above, but takes a URL so that meta-data may be retrieved over other protocols (ftp, etc.)

Definition at line 306 of file kfilemetainfo.cpp.

KFileMetaInfo::KFileMetaInfo  ) 
 

Default constructor.

This will create an invalid object (see isValid().

Definition at line 351 of file kfilemetainfo.cpp.

KFileMetaInfo::KFileMetaInfo const KFileMetaInfo original  ) 
 

Copy constructor.

This creates a copy of the original object, but that copy will point to the same data, so if you change the original, the copy will be changed, too. After all, they are referring to the same file.

Definition at line 344 of file kfilemetainfo.cpp.


Member Function Documentation

const KFileMetaInfo & KFileMetaInfo::operator= const KFileMetaInfo info  ) 
 

The assignment operator, so you can do e.g.

:

    KFileMetaInfo info;
    if (something) info = KFileMetaInfo("/the/file");

This will create a shared copy of the object. The actual data is automatically deleted if all copies go out of scope.

Definition at line 500 of file kfilemetainfo.cpp.

References d.

QStringList KFileMetaInfo::groups  )  const
 

Returns a list of all groups.

Returns:
the keys of the groups that the file has.

Definition at line 373 of file kfilemetainfo.cpp.

Referenced by contains(), containsGroup(), item(), preferredGroups(), and saveItem().

QStringList KFileMetaInfo::supportedGroups  )  const
 

Returns a list of all supported groups.

Returns:
the supported keys of the groups that the file has.

Definition at line 361 of file kfilemetainfo.cpp.

References isValid().

Referenced by editableGroups().

QStringList KFileMetaInfo::preferredGroups  )  const
 

Returns a list of the preferred groups.

Returns:
the keys of the preferred groups that the file has.

Definition at line 398 of file kfilemetainfo.cpp.

References group(), groups(), and isValid().

Referenced by item(), preferredKeys(), and saveItem().

QStringList KFileMetaInfo::preferredKeys  )  const
 

Returns a list of all preferred keys.

Returns:
a list of all preferred keys.

Definition at line 424 of file kfilemetainfo.cpp.

References preferredGroups().

Referenced by KFileItem::getToolTipText().

QStringList KFileMetaInfo::supportedKeys  )  const
 

Returns a list of supported keys.

Returns:
a list of supported keys

Definition at line 367 of file kfilemetainfo.cpp.

References isValid().

QStringList KFileMetaInfo::editableGroups  )  const
 

Returns the list of groups that you can add or remove from the file.

Returns:
the groups can be added or removed

Definition at line 383 of file kfilemetainfo.cpp.

References KFileMimeTypeInfo::Addable, KFileMimeTypeInfo::GroupInfo::attributes(), KFileMimeTypeInfo::Removable, and supportedGroups().

KFileMetaInfoItem KFileMetaInfo::item const QString key  )  const
 

Returns the KFileMetaInfoItem with the given key.

Parameters:
key the key of the item
Returns:
the item. Invalid if there is no item with the given key.

Definition at line 598 of file kfilemetainfo.cpp.

References groups(), KFileMetaInfoItem::isValid(), and preferredGroups().

Referenced by KFileItem::getToolTipText(), and saveItem().

KFileMetaInfoItem KFileMetaInfo::item const KFileMetaInfoItem::Hint  hint  )  const
 

Returns the KFileMetaInfoItem with the given hint.

Parameters:
hint the hint of the item
Returns:
the item. Invalid if there is no item with the given hint.

Definition at line 609 of file kfilemetainfo.cpp.

References groups(), KFileMetaInfoItem::isValid(), and preferredGroups().

KFileMetaInfoItem KFileMetaInfo::saveItem const QString key,
const QString preferredGroup = QString::null,
bool  createGroup = true
 

Saves the item with the given key.

Parameters:
key the key of the item
preferredGroup the preferred group, or QString::null
createGroup true to create the group if necessary
Returns:
the saved item

Definition at line 621 of file kfilemetainfo.cpp.

References addGroup(), KFileMetaInfoGroup::addItem(), group(), groups(), KFileMetaInfoItem::isValid(), isValid(), item(), preferredGroups(), and KFileMimeTypeInfo::GroupInfo::supportedKeys().

KFileMetaInfoGroup KFileMetaInfo::group const QString key  )  const
 

Returns the KFileMetaInfoGroup with the given key.

Parameters:
key the key of the item
Returns:
the group. Invalid if there is no group with the given key.

Definition at line 437 of file kfilemetainfo.cpp.

Referenced by addGroup(), preferredGroups(), and saveItem().

KFileMetaInfoGroup KFileMetaInfo::operator[] const QString key  )  const [inline]
 

Returns the KFileMetaInfoGroup with the given key.

Parameters:
key the key of the item
Returns:
the group. Invalid if there is no group with the given key.

Definition at line 1058 of file kfilemetainfo.h.

bool KFileMetaInfo::addGroup const QString name  ) 
 

Try to add the specified group.

This will only succeed if it is in the list of editableGroups().

Note:
that all non-variable items that belong to this group are automatically added as empty item.
Parameters:
name the name of the group to add
Returns:
true if successful, false if not

Definition at line 446 of file kfilemetainfo.cpp.

References KFileMimeTypeInfo::Addable, KFileMetaInfoGroup::appendItem(), KFileMimeTypeInfo::ItemInfo::attributes(), group(), isValid(), KFileMimeTypeInfo::ItemInfo::key(), KFileMimeTypeInfo::Modifiable, and KFileMetaInfoGroup::setAdded().

Referenced by saveItem().

bool KFileMetaInfo::removeGroup const QString name  ) 
 

Remove the specified group.

This will only succeed if it is in the list of editableGroups(). Beware that this also removes all the items in that group, so always ask the user before removing it!

Parameters:
name the name of the group to remove
Returns:
true if successful, false if not

Definition at line 483 of file kfilemetainfo.cpp.

References KFileMimeTypeInfo::Removable.

QStringList KFileMetaInfo::removedGroups  ) 
 

Returns a list of removed groups.

Returns:
a list of removed groups.

Definition at line 495 of file kfilemetainfo.cpp.

bool KFileMetaInfo::applyChanges  ) 
 

This method writes all pending changes of the meta info back to the file.

If any items are marked as removed, they are really removed from the list. The info object as well as all items are updated.

Returns:
true if successful, false if not

Definition at line 528 of file kfilemetainfo.cpp.

References kdDebug(), plugin(), and KFilePlugin::writeInfo().

bool KFileMetaInfo::contains const QString key  )  const
 

Checks whether an item with the given key exists.

Parameters:
key the key to check
Returns:
whether an item for this key exists.

Definition at line 582 of file kfilemetainfo.cpp.

References KFileMetaInfoGroup::contains(), and groups().

bool KFileMetaInfo::containsGroup const QString key  )  const
 

Checks whether a group with the given key exists.

Parameters:
key the key to check
Returns:
whether a group with this name exists.

Definition at line 593 of file kfilemetainfo.cpp.

References groups().

bool KFileMetaInfo::isValid  )  const
 

Returns true if the item is valid, i.e.

if actually represents the info about a file, false if the object is uninitialized.

Returns:
true if valid, false otherwise

Definition at line 513 of file kfilemetainfo.cpp.

Referenced by addGroup(), KFileItem::getToolTipText(), KFileItem::metaInfo(), mimeType(), plugin(), preferredGroups(), saveItem(), supportedGroups(), and supportedKeys().

bool KFileMetaInfo::isEmpty  )  const
 

Returns false if the object contains data, true if it's empty.

You'll get an empty object if no plugin for the file could be found.

Returns:
true if empty, false otherwise

Definition at line 519 of file kfilemetainfo.cpp.

Referenced by KFileItem::getToolTipText().

QString KFileMetaInfo::mimeType  )  const
 

Returns the mime type of file.

Returns:
the file's mime type

Definition at line 576 of file kfilemetainfo.cpp.

References isValid().

QString KFileMetaInfo::path  )  const
 

Returns the path of file - or QString::null if file is non-local.

Returns:
the file's path - or QString::null if file is non-local

Definition at line 718 of file kfilemetainfo.cpp.

KURL KFileMetaInfo::url  )  const
 

Returns the url of file.

Returns:
the file's url

Definition at line 723 of file kfilemetainfo.cpp.

KFilePlugin *const KFileMetaInfo::plugin  )  const [protected]
 

Returns:
a pointer to the plugin that belogs to this object's mimetype. It will be auto-loaded if it's currently not loaded

Definition at line 569 of file kfilemetainfo.cpp.

References isValid().

Referenced by applyChanges().


The documentation for this class was generated from the following files:
KDE Logo
This file is part of the documentation for kio Library Version 3.4.0.
Documentation copyright © 1996-2004 the KDE developers.
Generated on Wed May 4 07:13:45 2005 by doxygen 1.4.2 written by Dimitri van Heesch, © 1997-2003