detectSoundlevel-spike/sourceCode/trunk/Code/CoreAudio/Interfaces/IAudioSessionControl.cs

// -----------------------------------------
// SoundScribe (TM) and related software.
// 
// Copyright (C) 2007-2011 Vannatech
// http://www.vannatech.com
// All rights reserved.
// 
// This source code is subject to the MIT License.
// http://www.opensource.org/licenses/mit-license.php
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// -----------------------------------------

using System;
using System.Runtime.InteropServices;
using Vannatech.CoreAudio.Enumerations;

namespace Vannatech.CoreAudio.Interfaces
{
    /// <summary>
	/// Enables a client to configure the control parameters for an audio session and to monitor events in the session.
    /// </summary>
    /// <remarks>
	/// MSDN Reference: http://msdn.microsoft.com/en-us/library/dd368246.aspx
    /// </remarks>
	public partial interface IAudioSessionControl
    {
        // Note: Any changes to this interface should be repeated in IAudioSessionControl2.

		/// <summary>
		/// Retrieves the current state of the audio session.
		/// </summary>
		/// <param name="state">Receives the current session state.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetState(
			[Out] out AudioSessionState state);

		/// <summary>
		/// Retrieves the display name for the audio session.
		/// </summary>
		/// <param name="displayName">Receives a string that contains the display name.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetDisplayName(
			[Out] [MarshalAs(UnmanagedType.LPWStr)] out string displayName);

		/// <summary>
		/// Assigns a display name to the current audio session.
		/// </summary>
		/// <param name="displayName">A string that contains the new display name for the session.</param>
		/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int SetDisplayName(
			[In] [MarshalAs(UnmanagedType.LPWStr)] string displayName,
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

		/// <summary>
		/// Retrieves the path for the display icon for the audio session.
		/// </summary>
		/// <param name="iconPath">Receives a string that specifies the fully qualified path of the file that contains the icon.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetIconPath(
			[Out] [MarshalAs(UnmanagedType.LPWStr)] out string iconPath);

		/// <summary>
		/// Assigns a display icon to the current session.
		/// </summary>
		/// <param name="iconPath">A string that specifies the fully qualified path of the file that contains the new icon.</param>
		/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int SetIconPath(
			[In] [MarshalAs(UnmanagedType.LPWStr)] string iconPath,
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

		/// <summary>
		/// Retrieves the grouping parameter of the audio session.
		/// </summary>
		/// <param name="groupingId">Receives the grouping parameter ID.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetGroupingParam(
			[Out] out Guid groupingId);

		/// <summary>
		/// Assigns a session to a grouping of sessions.
		/// </summary>
		/// <param name="groupingId">The new grouping parameter ID.</param>
		/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int SetGroupingParam(
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid groupingId,
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

		/// <summary>
		/// Registers the client to receive notifications of session events, including changes in the session state.
		/// </summary>
		/// <param name="client">A client-implemented <see cref="IAudioSessionEvents"/> interface.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int RegisterAudioSessionNotification(
			[In] IAudioSessionEvents client);

		/// <summary>
		/// Deletes a previous registration by the client to receive notifications.
		/// </summary>
		/// <param name="client">A client-implemented <see cref="IAudioSessionEvents"/> interface.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int UnregisterAudioSessionNotification(
			[In] IAudioSessionEvents client);

		// TODO: Determine why these methods aren't part of the interface defined in audiopolicy.h

		///// <summary>
		///// Retrieves the time that the audio session last changed to the active state.
		///// </summary>
		///// <param name="date">Receives the time of the last activation.</param>
		///// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		//[PreserveSig]
		//int GetLastActivation(
		//    [Out] out DateTime date);

		///// <summary>
		///// Retrieves the time at which the audio session last became inactive.
		///// </summary>
		///// <param name="date">Receives the time of the last inactivation.</param>
		///// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		//[PreserveSig]
		//int GetLastInactivation(
		//    [Out] out DateTime date);
    }
}