RygelMediaContainer

## RygelMediaContainer RygelMediaContainer — This is a container (folder) for media items and child containers. |

## Synopsis

    #define             RYGEL_TYPE_MEDIA_CONTAINER
    void                rygel_media_container_get_children  (RygelMediaContainer *self,
                                                             guint offset,
                                                             guint max_count,
                                                             const gchar *sort_criteria,
                                                             GCancellable *cancellable,
                                                             GAsyncReadyCallback _callback_,
                                                             gpointer _user_data_);
    RygelMediaObjects * rygel_media_container_get_children_finish
                                                            (RygelMediaContainer *self,
                                                             GAsyncResult *_res_,
                                                             GError **error);
    void                rygel_media_container_find_object   (RygelMediaContainer *self,
                                                             const gchar *id,
                                                             GCancellable *cancellable,
                                                             GAsyncReadyCallback _callback_,
                                                             gpointer _user_data_);
    RygelMediaObject *  rygel_media_container_find_object_finish
                                                            (RygelMediaContainer *self,
                                                             GAsyncResult *_res_,
                                                             GError **error);
    void                rygel_media_container_updated       (RygelMediaContainer *self,
                                                             RygelMediaObject *object,
                                                             RygelObjectEventType event_type,
                                                             gboolean sub_tree_update);
    #define             RYGEL_MEDIA_CONTAINER_ANY
    #define             RYGEL_MEDIA_CONTAINER_UPNP_CLASS
    #define             RYGEL_MEDIA_CONTAINER_STORAGE_FOLDER
    #define             RYGEL_MEDIA_CONTAINER_MUSIC_ALBUM
    #define             RYGEL_MEDIA_CONTAINER_MUSIC_ARTIST
    #define             RYGEL_MEDIA_CONTAINER_MUSIC_GENRE
    #define             RYGEL_MEDIA_CONTAINER_ALBUM_SORT_CRITERIA
    gint                rygel_media_container_get_child_count
                                                            (RygelMediaContainer *self);
    void                rygel_media_container_set_child_count
                                                            (RygelMediaContainer *self,
                                                             gint value);
    const gchar *       rygel_media_container_get_sort_criteria
                                                            (RygelMediaContainer *self);
    void                rygel_media_container_set_sort_criteria
                                                            (RygelMediaContainer *self,
                                                             const gchar *value);
    struct              RygelMediaContainer;
    struct              RygelMediaContainerClass;
    enum                RygelObjectEventType;

## Object Hierarchy

      GObject
       +----RygelMediaObject
             +----RygelMediaContainer
                   +----RygelSimpleContainer

      GEnum
       +----RygelObjectEventType

## Known Derived Interfaces

RygelMediaContainer is required by RygelSearchableContainer, RygelTrackableContainer and RygelWritableContainer.

## Properties

      "child-count"              gint                  : Read / Write / Construct
      "ocm-flags"                GUPnPOCMFlags         : Read
      "sort-criteria"            gchar*                : Read / Write

## Signals

      "container-updated"                              : Run Last
      "sub-tree-updates-finished"                      : Run Last

## Description

It provides a basic serialization implementation (to DIDLLiteWriter).

A derived class should provide a working implementation of get_children and should emit the container_updated signal.

When used as a root container, you may wish to use the variables, such as REALNAME, in in the title. See the title property of the RygelMediaObject.

If the container should support UPnP search operations then you also implement the RygelSearchableContainer interface.

If the container should be writable, meaning that it allows adding (via upload), removal and editing of items then you should also implement the RygelWritableContainer interface.

If the container should support the change tracking profile of the UPnP ContentDirectory:3 specification then you should also implement the RygelTrackableContainer interface.

The RygelSimpleContainer class contains a simple memory-based container implementation, but most real-world uses will require custom container implementations.

## Details

### RYGEL_TYPE_MEDIA_CONTAINER

    #define RYGEL_TYPE_MEDIA_CONTAINER (rygel_media_container_get_type ())

The type for RygelMediaContainer.

### rygel_media_container_get_children ()

    void                rygel_media_container_get_children  (RygelMediaContainer *self,
                                                             guint offset,
                                                             guint max_count,
                                                             const gchar *sort_criteria,
                                                             GCancellable *cancellable,
                                                             GAsyncReadyCallback _callback_,
                                                             gpointer _user_data_);

Fetches the list of media objects directly under this container.

See also: ``rygel_media_container_get_children_finish()``

`self` : | the RygelMediaContainer instance
`offset` : | zero-based index of the first item to return. [in]
`max_count` : | maximum number of objects to return. [in]
`sort_criteria` : | sorting order of objects to return. [in]
`cancellable` : | optional cancellable for this operation. [in][allow-none]
`_callback_` : | callback to call when the request is satisfied. [scope async]
`_user_data_` : | the data to pass to `_callback_` function. [closure]

### rygel_media_container_get_children_finish ()

    RygelMediaObjects * rygel_media_container_get_children_finish
                                                            (RygelMediaContainer *self,
                                                             GAsyncResult *_res_,
                                                             GError **error);

Fetches the list of media objects directly under this container.

See also: ``rygel_media_container_get_children()``

`self` : | the RygelMediaContainer instance
`_res_` : | a GAsyncResult
`error` : | location to store the error occuring, or `NULL` to ignore
Returns : | A list of media objects.

### rygel_media_container_find_object ()

    void                rygel_media_container_find_object   (RygelMediaContainer *self,
                                                             const gchar *id,
                                                             GCancellable *cancellable,
                                                             GAsyncReadyCallback _callback_,
                                                             gpointer _user_data_);

Recursively searches this container for a media object with the given ID.

See also: ``rygel_media_container_find_object_finish()``

`self` : | the RygelMediaContainer instance
`id` : | ID of the media object to search for. [in]
`cancellable` : | optional cancellable for this operation. [in][allow-none]
`_callback_` : | callback to call when the request is satisfied. [scope async]
`_user_data_` : | the data to pass to `_callback_` function. [closure]

### rygel_media_container_find_object_finish ()

    RygelMediaObject *  rygel_media_container_find_object_finish
                                                            (RygelMediaContainer *self,
                                                             GAsyncResult *_res_,
                                                             GError **error);

Recursively searches this container for a media object with the given ID.

See also: ``rygel_media_container_find_object()``

`self` : | the RygelMediaContainer instance
`_res_` : | a GAsyncResult
`error` : | location to store the error occuring, or `NULL` to ignore
Returns : | the found media object.

### rygel_media_container_updated ()

    void                rygel_media_container_updated       (RygelMediaContainer *self,
                                                             RygelMediaObject *object,
                                                             RygelObjectEventType event_type,
                                                             gboolean sub_tree_update);

This method should be called each time this container is updated.

For instance, this should be called if there are metadata changes for this container, if items under it are removed or added, if there are metadata changes to items under it, etc.

If sub_tree_update is true then the caller should later emit the sub_tree_updates_finished signal on the root container of the sub-tree that was updated.

It will eventually result in the server emitting a UPnP LastChange event, though that may be for a batch of these calls.

See the "container_updated" signal.

`self` : | the RygelMediaContainer instance
`object` : | The object that has changed, or null to mean the container itself. [in][allow-none]
`event_type` : | This describes what actually happened to the object. [in]
`sub_tree_update` : | Whether the modification is part of a sub-tree update. [in]

### RYGEL_MEDIA_CONTAINER_ANY

    #define RYGEL_MEDIA_CONTAINER_ANY "DLNA.ORG_AnyContainer"

### RYGEL_MEDIA_CONTAINER_UPNP_CLASS

    #define RYGEL_MEDIA_CONTAINER_UPNP_CLASS "object.container"

### RYGEL_MEDIA_CONTAINER_STORAGE_FOLDER

    #define RYGEL_MEDIA_CONTAINER_STORAGE_FOLDER RYGEL_MEDIA_CONTAINER_UPNP_CLASS ".storageFolder"

### RYGEL_MEDIA_CONTAINER_MUSIC_ALBUM

    #define RYGEL_MEDIA_CONTAINER_MUSIC_ALBUM RYGEL_MEDIA_CONTAINER_UPNP_CLASS ".album.musicAlbum"

### RYGEL_MEDIA_CONTAINER_MUSIC_ARTIST

    #define RYGEL_MEDIA_CONTAINER_MUSIC_ARTIST RYGEL_MEDIA_CONTAINER_UPNP_CLASS ".person.musicArtist"

### RYGEL_MEDIA_CONTAINER_MUSIC_GENRE

    #define RYGEL_MEDIA_CONTAINER_MUSIC_GENRE RYGEL_MEDIA_CONTAINER_UPNP_CLASS ".genre.musicGenre"

### RYGEL_MEDIA_CONTAINER_ALBUM_SORT_CRITERIA

    #define RYGEL_MEDIA_CONTAINER_ALBUM_SORT_CRITERIA "+upnp:class," "+rygel:originalVolumeNumber," "+upnp:originalTrackNumber," "+dc:title"

### rygel_media_container_get_child_count ()

    gint                rygel_media_container_get_child_count
                                                            (RygelMediaContainer *self);

Get and return the current value of the "child-count" property.

`self` : | the RygelMediaContainer instance to query
Returns : | the value of the "child-count" property

### rygel_media_container_set_child_count ()

    void                rygel_media_container_set_child_count
                                                            (RygelMediaContainer *self,
                                                             gint value);

Set the value of the "child-count" property to `value`.

`self` : | the RygelMediaContainer instance to modify
`value` : | the new value of the "child-count" property

### rygel_media_container_get_sort_criteria ()

    const gchar *       rygel_media_container_get_sort_criteria
                                                            (RygelMediaContainer *self);

Get and return the current value of the "sort-criteria" property.

`self` : | the RygelMediaContainer instance to query
Returns : | the value of the "sort-criteria" property

### rygel_media_container_set_sort_criteria ()

    void                rygel_media_container_set_sort_criteria
                                                            (RygelMediaContainer *self,
                                                             const gchar *value);

Set the value of the "sort-criteria" property to `value`.

`self` : | the RygelMediaContainer instance to modify
`value` : | the new value of the "sort-criteria" property

### struct RygelMediaContainer

    struct RygelMediaContainer;

This is a container (folder) for media items and child containers.

It provides a basic serialization implementation (to DIDLLiteWriter).

A derived class should provide a working implementation of get_children and should emit the container_updated signal.

When used as a root container, you may wish to use the variables, such as REALNAME, in in the title. See the title property of the RygelMediaObject.

If the container should support UPnP search operations then you also implement the RygelSearchableContainer interface.

If the container should be writable, meaning that it allows adding (via upload), removal and editing of items then you should also implement the RygelWritableContainer interface.

If the container should support the change tracking profile of the UPnP ContentDirectory:3 specification then you should also implement the RygelTrackableContainer interface.

The RygelSimpleContainer class contains a simple memory-based container implementation, but most real-world uses will require custom container implementations.

### struct RygelMediaContainerClass

    struct RygelMediaContainerClass {
    	RygelMediaObjectClass parent_class;
    	void (*get_children) (RygelMediaContainer* self, guint offset, guint max_count, const gchar* sort_criteria, GCancellable* cancellable, GAsyncReadyCallback _callback_, gpointer _user_data_);
    	RygelMediaObjects* (*get_children_finish) (RygelMediaContainer* self, GAsyncResult* _res_, GError** error);
    	void (*find_object) (RygelMediaContainer* self, const gchar* id, GCancellable* cancellable, GAsyncReadyCallback _callback_, gpointer _user_data_);
    	RygelMediaObject* (*find_object_finish) (RygelMediaContainer* self, GAsyncResult* _res_, GError** error);
    };

The class structure for `RYGEL_TYPE_MEDIA_CONTAINER`. All the fields in this structure are private and should never be accessed directly.

RygelMediaObjectClass `parent_class`; | the parent class structure
`get_children` () | virtual method called by ``rygel_media_container_get_children()``
`get_children_finish` () | asynchronous finish function for `get_children`, called by ``rygel_media_container_get_children()``
`find_object` () | virtual method called by ``rygel_media_container_find_object()``
`find_object_finish` () | asynchronous finish function for `find_object`, called by ``rygel_media_container_find_object()``

### enum RygelObjectEventType

    typedef enum {
    	RYGEL_OBJECT_EVENT_TYPE_ADDED = 0,
    	RYGEL_OBJECT_EVENT_TYPE_MODIFIED = 1,
    	RYGEL_OBJECT_EVENT_TYPE_DELETED = 2
    } RygelObjectEventType;

`RYGEL_OBJECT_EVENT_TYPE_ADDED` |
`RYGEL_OBJECT_EVENT_TYPE_MODIFIED` |
`RYGEL_OBJECT_EVENT_TYPE_DELETED` |

## Property Details

### The `"child-count"` property

      "child-count"              gint                  : Read / Write / Construct

child-count.

Default value: 0

### The `"ocm-flags"` property

      "ocm-flags"                GUPnPOCMFlags         : Read

ocm-flags.

### The `"sort-criteria"` property

      "sort-criteria"            gchar*                : Read / Write

sort-criteria.

Default value: NULL

## Signal Details

### The `"container-updated"` signal

    void                user_function                      (RygelMediaContainer *media_container,
                                                            RygelMediaContainer *container,
                                                            RygelMediaObject    *object,
                                                            RygelObjectEventType event_type,
                                                            gboolean             sub_tree_update,
                                                            gpointer             user_data)            : Run Last

The container_updated signal is emitted if a child container under the tree of this container has been updated. The object parameter is set to the MediaObject that is the source of the container update. Note that it may even be set to the container itself.

See also: `rygel_media_container_updated()`.

`media_container` : | the RygelMediaContainer instance that received the signal
`container` : | The child container that has been updated.
`object` : | The object that has changed. This may be the container itself, or a child item.
`event_type` : | This describes what actually happened to the object.
`sub_tree_update` : | Whether the modification is part of a sub-tree update. See the "sub_tree_updates_finished" signal.
`user_data` : | user data set when the signal handler was connected.

### The `"sub-tree-updates-finished"` signal

    void                user_function                      (RygelMediaContainer *media_container,
                                                            RygelMediaObject    *sub_tree_root,
                                                            gpointer             user_data)            : Run Last

The sub_tree_updates_finished signal is emitted when all of the sub-tree operations are finished. See the "container_updated" signal.

`media_container` : | the RygelMediaContainer instance that received the signal
`sub_tree_root` : | - root of a sub-tree where all operations were performed.
`user_data` : | user data set when the signal handler was connected.