diff --git a/TestApps/Samples/Samples/MultithreadingSample.cs b/TestApps/Samples/Samples/MultithreadingSample.cs
index 0496589e..de1b0ccd 100644
--- a/TestApps/Samples/Samples/MultithreadingSample.cs
+++ b/TestApps/Samples/Samples/MultithreadingSample.cs
@@ -24,6 +24,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 using System;
+using System.ComponentModel;
 using System.Threading;
 using System.Threading.Tasks;
 using Xwt;
@@ -32,8 +33,9 @@ namespace Samples
 {
 	public class MultithreadingSample: VBox
 	{
-		Label l1, l2;
-		ToggleButton btn1, btn2;
+		SampleBGWorker worker4, worker5, worker6;
+		Label l1, l2, l3, l4, l5, l6;
+		ToggleButton btn1, btn2, btn3, btn4, btn5, btn6;
 
 		public MultithreadingSample ()
 		{
@@ -93,6 +95,166 @@ namespace Samples
 				else
 					worker2cancel.Cancel();
 			};
+
+
+			tbl.Add (new Label("BackgroundWorker:\n(XwtSynchronizationContext.Post)"), 0, r);
+			tbl.Add (l3 = new Label ("0"), 1, r);
+			tbl.Add (btn3 = new ToggleButton("Run"), 2, r++);
+
+			var worker3 = new BackgroundWorker ();
+			worker3.WorkerReportsProgress = true;
+			worker3.WorkerSupportsCancellation = true;
+			worker3.DoWork += BackgroundWorkerDoWork;
+			worker3.ProgressChanged += (sender, e) => l3.Text = e.ProgressPercentage.ToString ();
+
+			btn3.Toggled += delegate {
+				if (btn3.Active)
+					worker3.RunWorkerAsync ();
+				else
+					worker3.CancelAsync ();
+			};
+
+
+			tbl.Add (new Label("XwtSynchronizationContext.Send:"), 0, r);
+			tbl.Add (l4 = new Label ("0"), 1, r);
+			tbl.Add (btn4 = new ToggleButton("Run"), 2, r++);
+
+			worker4 = new SampleBGWorker ();
+			worker4.SynchronizationContext = SynchronizationContext.Current;
+			worker4.InvokeSynchronized = true;
+			worker4.Count += HandleCount4;
+
+			btn4.Toggled += delegate {
+				if (btn4.Active)
+					worker4.Start ();
+				else
+					worker4.Stop ();
+			};
+
+
+			tbl.Add (new Label("ISynchronizeInvoke.BeginInvoke:"), 0, r);
+			tbl.Add (l5 = new Label ("0"), 1, r);
+			tbl.Add (btn5 = new ToggleButton("Run"), 2, r++);
+
+			worker5 = new SampleBGWorker ();
+			worker5.InvokeSynchronized = false;
+			worker5.Count += HandleCount5;
+
+			btn5.Toggled += delegate {
+				if (btn5.Active)
+					worker5.Start ();
+				else
+					worker5.Stop ();
+			};
+
+
+			tbl.Add (new Label("ISynchronizeInvoke.Invoke:"), 0, r);
+			tbl.Add (l6 = new Label ("0"), 1, r);
+			tbl.Add (btn6 = new ToggleButton("Run"), 2, r++);
+
+			worker6 = new SampleBGWorker ();
+			worker6.InvokeSynchronized = true;
+			worker6.Count += HandleCount6;
+
+			btn6.Toggled += delegate {
+				if (btn6.Active)
+					worker6.Start ();
+				else
+					worker6.Stop ();
+			};
+		}
+
+		void BackgroundWorkerDoWork (object sender, DoWorkEventArgs e)
+		{
+			BackgroundWorker worker = (BackgroundWorker)sender;
+
+			int cnt2 = 0;
+			while (!worker.CancellationPending) {
+				Thread.Sleep (50);
+				worker.ReportProgress(cnt2++);
+			}
+			e.Cancel = true;
+		}
+
+		void HandleCount4 (object sender, CounterEventArgs e)
+		{
+			l4.Text = e.Cnt.ToString ();
+		}
+
+		void HandleCount5 (object sender, CounterEventArgs e)
+		{
+			l5.Text = e.Cnt.ToString ();
+		}
+
+		void HandleCount6 (object sender, CounterEventArgs e)
+		{
+			l6.Text = e.Cnt.ToString ();
+		}
+	}
+
+	class SampleBGWorker
+	{
+		CancellationTokenSource stopReq;
+		Task task;
+
+		public event EventHandler<CounterEventArgs> Count;
+
+		public SynchronizationContext SynchronizationContext { get; set; }
+
+		public bool InvokeSynchronized { get; set; }
+
+		public void Start ()
+		{
+			stopReq = new CancellationTokenSource ();
+			task = Task.Factory.StartNew (CounterThread, stopReq.Token);
+		}
+
+		public void Stop ()
+		{
+			stopReq.Cancel ();
+		}
+
+		void CounterThread ()
+		{
+			int cnt = 0;
+			while (!stopReq.Token.IsCancellationRequested) {
+				Thread.Sleep (50);
+				cnt++;
+				if (Count != null) {
+					if (SynchronizationContext == null) {
+						foreach (var del in Count.GetInvocationList()) {
+							var target = del.Target as ISynchronizeInvoke;
+							if (target != null) {
+								if (InvokeSynchronized)
+									target.Invoke (del, new object[] { this, new CounterEventArgs (cnt) });
+								else
+									target.BeginInvoke (del, new object[] { this, new CounterEventArgs (cnt) });
+							}
+						}
+					} else {
+						var args = new CounterEventArgs (cnt);
+						if (InvokeSynchronized) {
+							SynchronizationContext.Send (delegate {
+								Count (this, args);
+							}, null);
+						} else {
+							SynchronizationContext.Post (delegate {
+								Count (this, args);
+							}, null);
+						}
+					}
+				}
+			}
+		}
+	}
+
+	class CounterEventArgs : EventArgs
+	{
+		public int Cnt { get; private set; }
+
+		public CounterEventArgs (int cnt)
+		{
+			Cnt = cnt;
 		}
 	}
 }