More update for internal loop handling.

NTwain/Properties/VersionInfo.cs

@@ -12,8 +12,8 @@ namespace NTwain
     class _NTwainVersionInfo
     {
         // keep this same in majors releases
-        public const string Release = "0.10.0.0";
+        public const string Release = "0.11.0.0";
         // change this for each nuget release
-        public const string Build = "0.10.2";
+        public const string Build = "0.11.0";
     }
 }

NTwain/TwainSession.cs

@@ -32,8 +32,6 @@ namespace NTwain
             ((ITwainStateInternal)this).ChangeState(1, false);
             EnforceState = true;
 
-            Debug.WriteLine("current thread id =" + Thread.CurrentThread.ManagedThreadId);
-
             MessageLoop.Instance.EnsureStarted();
         }
 
@@ -298,8 +296,6 @@ namespace NTwain
                 rc = DGControl.Identity.CloseDS();
                 if (rc == ReturnCode.Success)
                 {
-                    MessageLoop.Instance.RemoveHook(HandleWndProcMessage);
-                    _callbackObj = null;
                     SupportedCaps = null;
                 }
             });
@@ -385,6 +381,14 @@ namespace NTwain
                 rc = DGControl.UserInterface.DisableDS(_twui);
                 if (rc == ReturnCode.Success)
                 {
+                    if (_callbackObj == null)
+                    {
+                        MessageLoop.Instance.RemoveHook(HandleWndProcMessage);
+                    }
+                    else
+                    {
+                        _callbackObj = null;
+                    }
                     OnSourceDisabled();
                 }
             });
@@ -418,26 +422,29 @@ namespace NTwain
             // success, the return status from DG_CONTROL / DAT_PENDINGXFERS / MSG_ENDXFER may
             // be ignored.
 
-            if (targetState < 7)
+            MessageLoop.Instance.Invoke(() =>
             {
-                DGControl.PendingXfers.EndXfer(new TWPendingXfers());
+                if (targetState < 7)
-            }
+                {
-            if (targetState < 6)
+                    DGControl.PendingXfers.EndXfer(new TWPendingXfers());
-            {
+                }
-                DGControl.PendingXfers.Reset(new TWPendingXfers());
+                if (targetState < 6)
-            }
+                {
-            if (targetState < 5)
+                    DGControl.PendingXfers.Reset(new TWPendingXfers());
-            {
+                }
-                DisableSource();
+                if (targetState < 5)
-            }
+                {
-            if (targetState < 4)
+                    DisableSource();
-            {
+                }
-                CloseSource();
+                if (targetState < 4)
-            }
+                {
-            if (targetState < 3)
+                    CloseSource();
-            {
+                }
-                CloseManager();
+                if (targetState < 3)
-            }
+                {
+                    CloseManager();
+                }
+            });
             EnforceState = origFlag;
         }
 
@@ -601,12 +608,10 @@ namespace NTwain
         IntPtr HandleWndProcMessage(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
         {
             // this handles the message from a typical WndProc message loop and check if it's from the TWAIN source.
-
+            if (State >= 5)
-            var winmsg = new MESSAGE(hwnd, msg, wParam, lParam);
-
-            if (State >= 4) // technically we should only handle on state >= 5 but there might be missed msgs if we wait until state changes after enabling ds
             {
                 // transform it into a pointer for twain
+                var winmsg = new MESSAGE(hwnd, msg, wParam, lParam);
                 IntPtr msgPtr = IntPtr.Zero;
                 try
                 {
@@ -614,7 +619,7 @@ namespace NTwain
                     msgPtr = Marshal.AllocHGlobal(Marshal.SizeOf(winmsg));
                     Marshal.StructureToPtr(winmsg, msgPtr, false);
 
-                    TWEvent evt = new TWEvent();
+                    var evt = new TWEvent();
                     evt.pEvent = msgPtr;
                     if (handled = (DGControl.Event.ProcessEvent(evt) == ReturnCode.DSEvent))
                     {

README.markdown

@@ -4,13 +4,13 @@ TWAIN Application-Side Library
 Info
 --------------------------------------
 This is a dotnet library created to work with [TWAIN](http://twain.org/) interface. 
-This project follows these general goals:
+This project has these features:
 
 * Targets latest TWAIN version (2.3 at the moment)
 * Supports all the TWAIN functions in the spec
-* Eventally work on platforms other than Windows (I can dream)
+* Hosts internal message loop so no need to hook into application UI thread
  
-The solution contains sample projects in winforms, wpf, and even (gasp!) console. 
+The solution contains tester projects in winform, wpf, and even (gasp!) console. 
 A nuget package is also [available here](https://www.nuget.org/packages/ntwain)
 
 Using the lib
@@ -23,3 +23,6 @@ when and how to use them. There are no high-level, single-line scan-a-page-for-m
 At the moment this lib does not provide ways to parse transferred image data and require
 consumers to do the conversion. The winform project contains one such 
 example for handling DIB image in native transfer.
+
+The main class to use is TwainSession. New it up, hook into the events, and start calling
+all the TWAIN functions provided through it.

Tests/Tester.Console/Program.cs

@@ -19,7 +19,7 @@ namespace Tester
         {
             // just an amusing example to do twain in console without UI
             DoTwainWork();
-            Console.WriteLine("Test completed, press Enter to exit.");
+            Console.WriteLine("Test started, press Enter to exit.");
             Console.ReadLine();
         }
 

Tests/Tester.Winform/TestForm.cs

@@ -345,7 +345,7 @@ namespace Tester.Winform
         {
             if (!_loadingCaps && _twain.State == 4)
             {
-                var sel = (int)comboDPI.SelectedItem;
+                var sel = (TWFix32)comboDPI.SelectedItem;
                 _twain.CapSetDPI(sel);
             }
         }