Present navigation markers in the Info panel to help users quickly navigate your content.
Framework
- AVKit
Overview
In addition to displaying metadata, the Info panel can also present navigation markers to help users quickly navigate your content. These markers represent points of interest within the media’s timeline to which you can skip by selecting the desired marker with the Siri Remote.
Set the Navigation Markers
AVPlayer in tvOS adds a navigation property. You can set this property with an array of AVNavigation objects to define the navigation markers for the current media.
An AVNavigation is composed of one or more AVTimed objects, each representing an individual marker presented in the player’s Info panel. Each AVTimed is composed of a time range in the asset’s timeline to which this marker applies, an array of AVMetadata objects to define the marker’s title, and optionally, its thumbnail artwork.
The following code example shows how you can present a chapter list for your media:
func setupPlayback() {
...
playerItem.navigationMarkerGroups = makeNavigationMarkerGroups()
...
}
private func makeNavigationMarkerGroups() -> [AVNavigationMarkersGroup] {
let chapters = [
["title": "Chapter 1", "imageName": "chapter1", "start": 0.0, "end": 60.0],
["title": "Chapter 2", "imageName": "chapter2", "start": 60.0, "end": 120.0],
["title": "Chapter 3", "imageName": "chapter3", "start": 120.0, "end": 180.0],
["title": "Chapter 4", "imageName": "chapter4", "start": 180.0, "end": 240.0]
]
var metadataGroups = [AVTimedMetadataGroup]()
// Iterate over the defined chapters, building an AVTimedMetadataGroup for each
for chapter in chapters {
metadataGroups.append(makeTimedMetadataGroup(for: chapter))
}
return [AVNavigationMarkersGroup(title: nil, timedNavigationMarkers: metadataGroups)]
}
private func makeTimedMetadataGroup(for chapter: [String: Any]) -> AVTimedMetadataGroup {
var metadata = [AVMetadataItem]()
// Create chapter title item
let title = chapter["title"] as! String
let titleItem = makeMetadataItem(AVMetadataCommonIdentifierTitle, value: title)
metadata.append(titleItem)
let imageName = chapter["imageName"] as! String
if let image = UIImage(named: imageName), let pngData = UIImagePNGRepresentation(image) {
// Create chapter thumbnail item
let imageItem = makeMetadataItem(AVMetadataCommonIdentifierArtwork, value: pngData)
metadata.append(imageItem)
}
// Create CMTimeRange
let timescale: Int32 = 600
let cmStartTime = CMTimeMakeWithSeconds(chapter["start"] as! TimeInterval, timescale)
let cmEndTime = CMTimeMakeWithSeconds(chapter["end"] as! TimeInterval, timescale)
let timeRange = CMTimeRangeFromTimeToTime(cmStartTime, cmEndTime)
return AVTimedMetadataGroup(items: metadata, timeRange: timeRange)
}
private func makeMetadataItem(_ identifier: String, value: Any) -> AVMetadataItem {
let item = AVMutableMetadataItem()
item.identifier = identifier
item.value = value as? NSCopying & NSObjectProtocol
item.extendedLanguageTag = "und"
return item.copy() as! AVMetadataItem
}