| Inherits from | |
| Conforms to | |
| Framework | /System/Library/Frameworks/AVFoundation.framework |
| Availability | Available in iOS 4.0 and later. |
| Declared in | AVPlayerItem.h |
An AVPlayerItem represents the presentation state of an asset that’s played by an AVPlayer object, and lets you observe that state.
A object carries a reference to an AVAsset object and presentation settings for that asset, including track enabled state. If you need to inspect the media assets themselves, you should message the AVAsset object itself.
You can initialize a player item using an URL (playerItemWithURL: and initWithURL:); the resource types referenced by the URL may include, but aren't necessarily limited to, those with the following corresponding UTIs:
kUTTypeQuickTimeMovie, (.mov, .qt)
kUTTypeMPEG4 (.mp4)
@"public.3gpp" (.3gp, .3gpp)
kUTTypeMPEG4Audio (.m4a)
@"com.apple.coreaudio-format" (.caf)
@"com.microsoft.waveform-audio" (.wav)
@"public.aiff-audio" (.aif)
@"public.aifc-audio" (also .aif)
@"org.3gpp.adaptive-multi-rate-audio" (.amr)
If you want to play an asset more than once within a sequence of items, you must create independent instances of AVPlayerItem for each placement in the player's queue.
asset property
tracks property
status property
loadedTimeRanges property
presentationSize property
timedMetadata property
seekableTimeRanges property
error property
playbackLikelyToKeepUp property
playbackBufferEmpty property
playbackBufferFull property
– currentTime
forwardPlaybackEndTime property
reversePlaybackEndTime property
audioMix property
videoComposition property
For more about Objective-C properties, see “Properties” in The Objective-C Programming Language.
The underlying asset provided during initialization. (read-only)
@property(nonatomic, readonly) AVAsset *asset
AVPlayerItem.hThe audio mix parameters to be applied during playback.
@property(nonatomic, copy) AVAudioMix *audioMix
AVPlayerItem.hIf the receiver's status is AVPlayerItemStatusFailed, this describes the error that caused the failure. (read-only)
@property(nonatomic, readonly) NSError *error
The value of this property is an error that describes what caused the receiver to no longer be able to be played.
If the receiver's status is not AVPlayerItemStatusFailed, the value of this property is nil.
AVPlayerItem.hThe time at which forward playback ends.
@property(nonatomic) CMTime forwardPlaybackEndTime
AVPlayerItem.hThe time ranges of the item that have been loaded. (read-only)
@property(nonatomic, readonly) NSArray *loadedTimeRanges
The array contains NSValue objects containing a CMTimeRange value.
AVPlayerItem.hIndicates whether playback has consumed all buffered media and that playback will stall or end. (read-only)
@property(nonatomic, readonly, getter=isPlaybackBufferEmpty) BOOL playbackBufferEmpty
AVPlayerItem.hIndicates whether the internal media buffer is full and that further I/O is suspended. (read-only)
@property(nonatomic, readonly, getter=isPlaybackBufferFull) BOOL playbackBufferFull
AVPlayerItem.hIndicates whether the item will likely play through without stalling (read-only)
@property(nonatomic, readonly, getter=isPlaybackLikelyToKeepUp) BOOL playbackLikelyToKeepUp
AVPlayerItem.hThe size at which the visual portion of the item is presented by the player. (read-only)
@property (nonatomic, readonly) CGSize presentationSize;
You can scale the presentation size to fit within the bounds of a player layer using its videoGravity property.
AVPlayerItem.hThe time at which reverse playback ends.
@property(nonatomic) CMTime reversePlaybackEndTime
AVPlayerItem.h(read-only)
@property(nonatomic, readonly) NSArray *seekableTimeRanges
The array contains NSValue objects containing a CMTimeRange value.
AVPlayerItem.hThe status of the player item. (read-only)
@property(nonatomic, readonly) AVPlayerItemStatus status
For example, whether the item is playable. For possible values, see “AVPlayerItemStatus.”
AVPlayerItem.hThe timed metadata played most recently by the media stream. (read-only)
@property(nonatomic, readonly) NSArray *timedMetadata
The array contains instances of AVMetadataItem.
AVPlayerItem.hAn array of AVPlayerItemTrack objects. (read-only)
@property(nonatomic, readonly) NSArray *tracks
This property can change dynamically during playback. You can observe it using key-value observing.
AVPlayerItem.hThe video composition settings to be applied during playback.
@property(nonatomic, copy) AVVideoComposition *videoComposition
AVPlayerItem.hReturns a new player item for a given asset.
+ (AVPlayerItem *)playerItemWithAsset:(AVAsset *)asset
An asset to play.
A new player item, initialized to play asset.
AVPlayerItem.hReturns a new player item, prepared to use a given URL.
+ (AVPlayerItem *)playerItemWithURL:(NSURL *)URL
An URL.
A new player item, prepared to use URL.
This method immediately returns the item, but with the status AVPlayerItemStatusUnknown.
If the URL contains valid data that can be used by the player item, the status later changes to AVPlayerItemStatusReadyToPlay.
If the URL contains no valid data or otherwise can't be used by the player item, the status later changes to AVPlayerItemStatusFailed.
AVPlayerItem.hReturns the current time of the item.
- (CMTime)currentTime
The current time of the item.
AVPlayerItem.hInitializes a new player item for a given asset.
- (id)initWithAsset:(AVAsset *)asset
An asset to play.
The receiver, initialized to play asset.
AVPlayerItem.hPrepares a player item with a given URL.
- (id)initWithURL:(NSURL *)URL
An URL.
The receiver, prepared to use URL.
This method immediately returns the item, but with the status AVPlayerItemStatusUnknown.
If the URL contains valid data that can be used by the player item, the status later changes to AVPlayerItemStatusReadyToPlay.
If the URL contains no valid data or otherwise can't be used by the player item, the status later changes to AVPlayerItemStatusFailed.
AVPlayerItem.hMoves the playback cursor to a given date.
- (BOOL)seekToDate:(NSDate *)date
The date to which to move the playback cursor.
YES if the playhead was moved to date, otherwise NO.
For playback content that is associated with a range of dates, this method moves the playhead to point within that range. This method will fail (return NO) if date is outside the range or if the content is not associated with a range of dates.
AVPlayerItem.hMoves the playback cursor to a given time.
- (void)seekToTime:(CMTime)time
The time to which to move the playback cursor.
The time seeked to may differ from the specified time for efficiency. For sample accurate seeking see seekToTime:toleranceBefore:toleranceAfter:.
AVPlayerItem.hMoves the playback cursor within a specified time bound.
- (void)seekToTime:(CMTime)time toleranceBefore:(CMTime)toleranceBefore toleranceAfter:(CMTime)toleranceAfter
The time to which you would like to move the playback cursor.
The tolerance allowed before time.
The tolerance allowed after time.
The time seeked to will be within the range [time-beforeTolerance, time+afterTolerance], and may differ from the specified time for efficiency. If you pass kCMTimeZero for both toleranceBefore and toleranceAfter (to request sample accurate seeking), you may incur additional decoding delay.
Passing kCMTimePositiveInfinity for both toleranceBefore and toleranceAfter is the same as messaging seekToTime: directly.
AVPlayerItem.hMoves the player’s current item’s current time forward or backward by a specified number of steps.
- (void)stepByCount:(NSInteger)stepCount
The number of steps by which to move.
A positive number steps forward, a negative number steps backward.
The size of each step depends on the receiver’s enabled AVPlayerItemTrack objects (see tracks).
AVPlayerItem.hConstants that represent the status of an item
enum {
AVPlayerItemStatusUnknown,
AVPlayerItemStatusReadyToPlay,
AVPlayerItemStatusFailed
};
typedef NSInteger AVPlayerItemStatus;
AVPlayerItemStatusUnknownThe item’s status is unknown.
Available in iOS 4.0 and later.
Declared in AVPlayerItem.h.
AVPlayerItemStatusReadyToPlayThe item is ready to play.
Available in iOS 4.0 and later.
Declared in AVPlayerItem.h.
AVPlayerItemStatusFailedThe item cannot be played.
Available in iOS 4.0 and later.
Declared in AVPlayerItem.h.
Posted when the item has played to its end time.
The notification’s object is the item that finished playing.
Important: This notification may be posted on a different thread than the one on which the observer was registered.
AVPlayerItem.hLast updated: 2010-05-15