1e41f4b71Sopenharmony_ci# MediaKeySession_Callback
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4e41f4b71Sopenharmony_ci## 概述
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6e41f4b71Sopenharmony_ciMediaKeySession_Callback结构体，用于监听密钥过期、密钥更改等事件，不返回媒体密钥会话实例，适用于单媒体密钥会话解密场景。
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8e41f4b71Sopenharmony_ci**起始版本：** 11
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10e41f4b71Sopenharmony_ci**相关模块：**[Drm](_drm.md)
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13e41f4b71Sopenharmony_ci## 汇总
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16e41f4b71Sopenharmony_ci### 成员变量
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18e41f4b71Sopenharmony_ci| 名称 | 描述 | 
19e41f4b71Sopenharmony_ci| -------- | -------- |
20e41f4b71Sopenharmony_ci| [MediaKeySession_EventCallback](_drm.md#mediakeysession_eventcallback) [eventCallback](_drm.md#eventcallback) | 正常事件回调，如密钥过期等。 | 
21e41f4b71Sopenharmony_ci| [MediaKeySession_KeyChangeCallback](_drm.md#mediakeysession_keychangecallback) [keyChangeCallback](_drm.md#keychangecallback) | 密钥更改事件的密钥更改回调。 | 
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