internal override void Start(IWinMessageFilter filter)
{
if (_dispatcher == null)
{
// using this hack so the new thread will start running before this function returns
using (var hack = new WrappedManualResetEvent())
{
var loopThread = new Thread(new ThreadStart(() =>
{
PlatformInfo.Current.Log.Debug("NTwain internal message loop is starting.");
_dispatcher = Dispatcher.CurrentDispatcher;
if (!PlatformInfo.Current.IsOnMono)
{
_hook = new WindowsHook(filter);
Handle = _hook.Handle;
}
hack.Set();
Dispatcher.Run();
// if dispatcher shutsdown we'll get here so make everything uninitialized
_dispatcher = null;
if (_hook != null)
{
_hook.Dispose();
_hook = null;
Handle = IntPtr.Zero;
}
}));
loopThread.IsBackground = true;
loopThread.SetApartmentState(ApartmentState.STA);
loopThread.Start();
hack.Wait();
}
}
}
public override void Invoke(Action action)
{
if (_dispatcher == null)
{
throw new InvalidOperationException(Resources.MsgLoopUnavailble);
}
Exception error = null;
if (_dispatcher.CheckAccess())
{
action();
}
else if (PlatformInfo.Current.IsOnMono)
{
using (var man = new WrappedManualResetEvent())
{
_dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
{
try
{
action();
}
catch (Exception ex) { error = ex; }
finally
{
man.Set();
}
}));
man.Wait();
}
}
else
{
_dispatcher.Invoke(DispatcherPriority.Normal, new Action(() =>
{
try
{
action();
}
catch (Exception ex) { error = ex; }
}));
}
if (error != null)
{
Rethrow(error);
}
}