# PlaybackSession

Source: https://www.nianticspatial.com/docs/api/kotlin/com.nianticspatial.nsdk.playback.PlaybackSession/

PlaybackSession

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## Declaration

class PlaybackSession

## Summary

Runs a timed loop over a [PlaybackDataset], loading one frame per tick and notifying a listener.
Use [play] to begin playback and [pause] to stop; the loop wraps to frame 0 at end.
Call [setOnFrameListener] before [play] to receive each [PlaybackFrame]; the listener may be
invoked from a background thread (post to main in the sample if needed).

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## Properties

| Name | Type | Summary |
| --- | --- | --- |
| dataset | PlaybackDataset | - |

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## Functions

| Name | Type | Summary |
| --- | --- | --- |
| clearOnFrameListener | void | Clears the frame listener. |
| currentFrameIndex | Int | Current frame index (0 until [dataset][PlaybackDataset].frameCount). |
| currentPlaybackFrame | PlaybackFrame? | Last frame delivered to the listener; null before any frame or after [pause]. |
| dispose | void | Stops playback and releases all held references. Call from the owning component's teardown(e.g. [androidx.lifecycle.ViewModel.onCleared] or [android.app.Activity.onDestroy]) toprevent the listener lambda from retaining a reference to a destroyed component.After dispose, this session should not be reused. |
| hasDepth | Boolean | Delegates to [PlaybackDataset.hasDepth]. |
| isPlaying | Boolean | True when the session has been started and not yet paused. |
| pause | void | Stops the playback loop. Current index is preserved so [play] resumes from the next frame. |
| play | void | Starts the playback loop on a background thread. Delivers frames every [PlaybackDataset.frameInterval] seconds;at end of dataset wraps to index 0. No-op if already playing. |
| seekToStart | void | Resets playback to the first frame. Call before [play] to begin from the beginning; safe to call while paused. |
| setOnFrameListener | void | Sets the callback invoked for each loaded frame. Call before [play]. |

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