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This is the class for objects that hold 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.
| typedef KFileMimeTypeInfo::Hint Hint | Hint |
| typedef KFileMimeTypeInfo::Unit Unit | Unit |
| typedef KFileMimeTypeInfo::Attributes Attributes | Attributes |
| enum What { Fastest = 0x1, DontCare = 0x2, TechnicalInfo = 0x4, ContentInfo = 0x8, ExtenedAttr = 0x10, Thumbnail = 0x20, Preferred = 0x40, Everything = 0xffff } | 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.
Fastest do the fastest possible read and omit all items
that might need a significantly longer time than
the others
Everything read everything, even if it might take a while
DontCare let the plugin decide what to read
TechnicalInfo extract technical details about the file, like
e.g. play time, resolution or a compression type
ContentInfo read information about the content of the file,
like comments or id3 tags
ExtendedAttr 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
| KFileMetaInfo ( const QString& path,
const QString& mimeType = QString::null,
uint what = Fastest)
| KFileMetaInfo |
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.
|
| KFileMetaInfo ()
| KFileMetaInfo |
Default constructor. This will create an invalid object (see isValid().
| KFileMetaInfo ( const KFileMetaInfo& original)
| KFileMetaInfo |
Copy constructor
| ~KFileMetaInfo ()
| ~KFileMetaInfo |
| const KFileMetaInfo& operator= (const KFileMetaInfo& info )
| operator= |
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
| QStringList groups ()
| groups |
[const]
Returns: all keys groups that the file has.
| QStringList supportedGroups ()
| supportedGroups |
[const]
| QStringList preferredGroups ()
| preferredGroups |
[const]
| QStringList preferredKeys ()
| preferredKeys |
[const]
| QStringList supportedKeys ()
| supportedKeys |
[const]
| QStringList editableGroups ()
| editableGroups |
[const]
Returns: the list of groups that you can add or remove from the file.
| KFileMetaInfoItem item (const QString& key)
| item |
[const]
| KFileMetaInfoItem item (const KFileMetaInfoItem::Hint hint)
| item |
[const]
| KFileMetaInfoItem saveItem ( const QString& key,
const QString& preferredGroup = QString::null,
bool createGroup = true )
| saveItem |
| KFileMetaInfoGroup group (const QString& key)
| group |
[const]
| KFileMetaInfoGroup operator[] (const QString& key)
| operator[] |
[const]
| bool addGroup ( const QString& name )
| addGroup |
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.
| bool removeGroup ( const QString& name )
| removeGroup |
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!
| QStringList removedGroups ()
| removedGroups |
| bool applyChanges ()
| 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
| bool contains ( const QString& key )
| contains |
[const]
Returns: whether an item for this key exists.
| bool containsGroup ( const QString& key )
| containsGroup |
[const]
Returns: whether a group with this name exists.
| const QVariant value ( const QString& key )
| value |
[const]
| bool isValid ()
| 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
| bool isEmpty ()
| 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.
| QString mimeType ()
| mimeType |
[const]
| QString path ()
| path |
[const]
| friend QDataStream& operator >> (QDataStream& s, KFileMetaInfo& )
| operator >> |
| friend QDataStream& operator << (QDataStream& s, const KFileMetaInfo& )
| operator << |
| friend class KFilePlugin | KFilePlugin |
| KFileMetaInfoGroup appendGroup (const QString& name)
| appendGroup |
[protected]
| KFilePlugin * const plugin ()
| plugin |
[protected const]
Returns: a pointer to the plugin that belogs to this object's mimetype. It will be auto-loaded if it's currently not loaded
| void ref ()
| ref |
[protected]
| void deref ()
| deref |
[protected]
| Data* d | d |
[protected]
| Generated by: dfaure on faure on Tue Apr 16 08:49:48 2002, using kdoc 2.0a53. |