Introduction

The Player API is the top-level API. This API exposes:

• basic functions to manipulate video playback, such as start and pause;
• properties to check states and values, such as the playhead position;
• events to track changes.

The list below overviews how-to articles related to the Player API.

• How do you know when a stream or an advertisement is playing?
• How to measure time-to-first-frame
• How can we track the first play(ing) event?
• How to track player states

Events

As a developer, you can programmatically attach event listeners to different APIs. Event listeners are often used to implement a custom UI or to implement a custom analytics integration.

The THEOplayer API exposes many events across different interfaces, as can be seen in the graphic below. Furthermore, most events exist in all SDKs (Web, iOS-based, Android-based and Roku).

The table below gives an overview of a subset of the available events per interface in the THEOplayer Web SDK.

Interface	Event	Description
Player	canplay	Fired when the player can resume playback of the media data.
Player	canplaythrough	Fired when the player can resume playback of the media data and buffering is unlikely.
Player	contentprotectionerror	Fired when an error related to content protection occurs.
Player	contentprotectionsuccess	Fired when the key is usable for decryption.
Player	currentsourcechange	Fired when the current source, which is chosen from ChromelessPlayer.source.sources, changes.
Player	destroy	Fired when the the player is destroyed.
Player	dimensionchange	Fired when the dimensions of the HTML element changes.
Player	durationchange	Fired when ChromelessPlayer.duration changes.
Player	emptied	Fired when the player's source is cleared.
Player	encrypted	Fired when the player encounters key system initialization data in the media data.
Player	ended	Fired when playback has stopped because the end of the media resource was reached.
Player	error	Fired when an error occurs.
Player	loadeddata	Fired when the player can render the media data at the current playback position for the first time.
Player	loadedmetadata	Fired when the player determines the duration and dimensions of the media resource.
Player	loadstart	Fired when the player starts loading the manifest.
Player	manifestupdate	Fired when the manifest is updated.
Player	pause	Fired when ChromelessPlayer.paused changes to true.
Player	play	Fired when ChromelessPlayer.paused changes to false.
Player	playing	Fired when playback is ready to start after having been paused or delayed due to lack of media data.
Player	progress	Fired when the player loaded media data.
Player	ratechange	Fired when ChromelessPlayer.playbackRate changes.
Player	readystatechange	Fired when ChromelessPlayer.readyState changes.
Player	representationchange	Fired when the current representation changes.
Player	resize	Fired when either ChromelessPlayer.videoWidth or ChromelessPlayer.videoHeight changes.
Player	seeked	Fired when ChromelessPlayer.seeking changes to false after the current playback position was changed.
Player	seeking	Fired when ChromelessPlayer.seeking changes to true, and the player has started seeking to a new position.
Player	segmentnotfound	Fired when a segment can not be found.
Player	sourcechange	Fired when ChromelessPlayer.source changes.
Player	timeupdate	Fired when the current playback position changed as part of normal playback or in an especially interesting way, for example discontinuously.
Player	volumechange	Fired when ChromelessPlayer.volume changes.
Player	waiting	Fired when playback has stopped because the next frame is not available, but the player expects that frame to become available in due course.
Player	currentTime	The current playback position of the media, in seconds.
Player	currentProgramDateTime	The current playback position of the media, as a timestamp.
Player	muted	Whether audio is muted.
Player	...	...
Ads (Client-Side)	adbegin	Fired when an ad begins.
Ads (Client-Side)	adbreakbegin	Fired when an ad break begins.
Ads (Client-Side)	adbreakchange	Fired when an ad break changes.
Ads (Client-Side)	adbreakend	Fired when an ad break ends.
Ads (Client-Side)	adbuffering	Fired when the ad has stalled playback to buffer.
Ads (Client-Side)	addad	Fired when an ad is added.
Ads (Client-Side)	addadbreak	Fired when an ad break is added.
Ads (Client-Side)	adend	Fired when an ad ends.
Ads (Client-Side)	aderror	Fired when an ad errors.
Ads (Client-Side)	adfirstquartile	Fired when an ad reaches the first quartile.
Ads (Client-Side)	adimpression	Fired when an ad counts as an impression.
Ads (Client-Side)	adloaded	Fired when an ad is loaded.
Ads (Client-Side)	admetadata	Fired when an ads list is loaded.
Ads (Client-Side)	admidpoint	Fired when an ad reaches the mid point.
Ads (Client-Side)	adskip	Fired when an ad is skipped.
Ads (Client-Side)	adthirdquartile	Fired when an ad reaches the third quartile.
Ads (Client-Side)	removeadbreak	Fired when an ad break is removed.
Ads (Client-Side)	updatead	Fired when an ad is updated.
Ads (Client-Side)	updateadbreak	Fired when an AdBreak is updated.
Vendor Cast	statechange	Fired when the state changes.
Chromecast	error	Fired when an error occurs while casting or trying to cast.
Track List	addtrack	Fired when a track is added.
Track List	change	Fired when a track is activated or deactivated.
Track List	removetrack	Fired when a track is removed.
Track	change	Fired when a media track's enabled or a text track's changes.
Track	update	Fired when the track updates.
Media Track	activequalitychanged	Fired when the media track's active quality changes.
Media Track	qualityunavailable	Fired when a quality of the track becomes unavailable.
Media Track	targetqualitychanged	Fired when the media track's target quality changes.
Text Track	addcue	Fired when a cue is added to the track.
Text Track	cuechange	Fired when a cue of the track changes.
Text Track	entercue	Fired when a cue of the track enters.
Text Track	error	Fired when an error occurred while loading or parsing the track.
Text Track	exitcue	Fired when a cue of the track exits.
Text Track	readystatechange	Fired when the text track's changes.
Text Track	removecue	Fired when a cue of the track is removed.
Text Track	typechange	Fired when the text track's changes.
Text Track Cue	enter	Fired when the cue is entered.
Text Track Cue	exit	Fired when the cue is exited.
Text Track Cue	update	Fired when the cue is updated.
Presentation	error	Fired when an error occurs.
Presentation	presentationmodechange	Fired when the presentation mode changes.
VR	directionchange	Fired when the VR.direction changes.
VR	error	Fired when an error occurs.
VR	statechange	Fired when the VR.state changes.
VR	stereochange	Fired when the VR.stereo changes.
Verizon Media	assetinforesponse	Fired when an asset info response is received.
Verizon Media	pingerror	Fired when an error or invalid response is received from the Ping API.
Verizon Media	pingresponse	Fired when a Ping response is received.
Verizon Media	preplayresponse	Fired when a Preplay response is received.
Verizon Media	ads	The Verizon Media SSAI API.
Verizon Media	assets	List of Verizon Media assets.
Verizon Media Ad Break List	addadbreak	Fired when the ad break is added.
Verizon Media Ad Break List	removeadbreak	Fired when the ad break is removed.
Verizon Media Ad Break	adbreakbegin	Fired when the ad break begins.
Verizon Media Ad Break	adbreakend	Fired when the ad break ends.
Verizon Media Ad Break	adbreakskip	Fired when the ad break is skipped.
Verizon Media Ad Break	updateadbreak	Fired when the ad break is updated.
Verizon Media Ad	adbegin	Fired when an ad begins.
Verizon Media Ad	adcomplete	Fired when the ad is completed.
Verizon Media Ad	adend	Fired when the ad ends.
Verizon Media Ad	adfirstquartile	Fired when the ad reaches the first quartile.
Verizon Media Ad	admidpoint	Fired when the ad reaches the mid point.
Verizon Media Ad	adthirdquartile	Fired when the ad reaches the third quartile.

Our APIs are continuously evolving, and so is our list of events. Refer to our API references of our SDKs to go through the latest sets of events:

• Web SDK
• iOS SDK
• Android SDK