1# MediaKeySession_Callback
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4## Overview
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6The MediaKeySession_Callback struct describes the callback used to listen for events such as media key expiry or change, without returning media key session instances. It applies to the scenario where a single media key session needs to be decrypted.
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8**Since**: 11
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10**Related module**: [Drm](_drm.md)
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13## Summary
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16### Member Variables
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18| Name| Description|
19| -------- | -------- |
20| [MediaKeySession_EventCallback](_drm.md#mediakeysession_eventcallback) [eventCallback](_drm.md#eventcallback) | Event callback, for example, a media key expiry event.|
21| [MediaKeySession_KeyChangeCallback](_drm.md#mediakeysession_keychangecallback) [keyChangeCallback](_drm.md#keychangecallback) | Callback of the media key change event.|
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