AudioSessionState Enumeration

The AudioSessionState enumeration defines constants that indicate the current state of an audio session.

Syntax

typedef enum _AudioSessionState
{
    AudioSessionStateInactive = 0,
    AudioSessionStateActive = 1,
    AudioSessionStateExpired = 2
} AudioSessionState;  

Remarks

When a client opens a session by assigning the first stream to the session (by calling the IAudioClient::Initialize method), the initial session state is inactive. The session state changes from inactive to active when a stream in the session begins running (because the client has called the IAudioClient::Start method). The session changes from active to inactive when the client stops the last running stream in the session (by calling the IAudioClient::Stop method). The session state changes to expired when the client destroys the last stream in the session by releasing all references to the stream object.

The system volume-control program, Sndvol, displays volume controls for both active and inactive sessions. Sndvol stops displaying the volume control for a session when the session state changes to expired. For more information about Sndvol, see Audio Sessions.

Constants

Requirements

Header: Declared in audiosessiontypes.h.

Library: Use mmdevapi.lib.