/// <summary>
/// Initializes the SDK
/// </summary>
/// <param name="useCallingThread">If true, the calling thread will be used as SDK main thread;
/// if false, a separate thread will be created</param>
public CanonAPI(bool useCallingThread)
{
try
{
//Ensure that only one caller at a time can increase the counter
lock (InitLock)
{
//If no instance exists yet, initialize everything
if (RefCount == 0)
{
if (useCallingThread)
{
if (Thread.CurrentThread.GetApartmentState() != ApartmentState.STA)
{
throw new ThreadStateException("Calling thread must be in STA");
}
ErrorHandler.CheckError(this, CanonSDK.EdsInitializeSDK());
}
else
{
//Trying to trigger DllNotFoundException so it's not thrown
//in the event loop on a different thread:
CanonSDK.EdsRelease(IntPtr.Zero);
//Start the main thread where SDK will run on
MainThread = new ApiThread();
MainThread.Start();
//Initialize the SDK on the main thread
MainThread.Invoke(() => ErrorHandler.CheckError(this, CanonSDK.EdsInitializeSDK()));
}
CanonSDK.InitializeVersion();
//Subscribe to the CameraAdded event
CameraAddedEvent = new SDKCameraAddedHandler(CanonAPI_CameraAddedEvent);
ErrorHandler.CheckError(this, CanonSDK.EdsSetCameraAddedHandler(CameraAddedEvent, IntPtr.Zero));
_IsSDKInitialized = true;
}
RefCount++;
}
}
catch (Exception e)
{
IsDisposed = true;
if (MainThread?.IsRunning == true)
{
MainThread.Shutdown();
}
throw;
}
}
/// <summary>
/// Terminates the SDK and disposes resources
/// </summary>
/// <param name="managed">True if called from Dispose, false if called from the finalizer/destructor</param>
protected virtual void Dispose(bool managed)
{
//Ensure that only one caller at a time can decrease the counter
lock (InitLock)
{
if (!IsDisposed)
{
//If it's the last instance, release everything
if (RefCount == 1)
{
_IsSDKInitialized = false;//Set beforehand because if an error happens, the SDK will be in an unstable state anyway
//Remove event handler for the CameraAdded event
ErrorCode err = CanonSDK.EdsSetCameraAddedHandler(null, IntPtr.Zero);
if (managed)
{
ErrorHandler.CheckError(this, err);
//Dispose all the connected cameras
CurrentCameras.ForEach(t => t.Dispose());
}
//Terminate the SDK
if (MainThread?.IsRunning == true)
{
err = MainThread.Invoke(() => { return(CanonSDK.EdsTerminateSDK()); });
}
//Close the main thread
if (MainThread?.IsRunning == true)
{
MainThread.Shutdown();
}
if (managed)
{
ErrorHandler.CheckError(this, err);
}
}
RefCount--;
IsDisposed = true;
}
}
}