Dispatcher: Run() can be used more than once

When Run() was invoked a second time, main_execution_frame had the Continue
flag set to false. So it did not work correctly.

2 files changed, 9 insertions, 0 deletions

diff --git a/mcs/class/WindowsBase/System.Windows.Threading/Dispatcher.cs b/mcs/class/WindowsBase/System.Windows.Threading/Dispatcher.cs
index f9c11ccc8fe..59a72efdb16 100644
--- a/mcs/class/WindowsBase/System.Windows.Threading/Dispatcher.cs
+++ b/mcs/class/WindowsBase/System.Windows.Threading/Dispatcher.cs
@@ -334,6 +334,9 @@ namespace System.Windows.Threading {
 		[SecurityCritical]
 		public static void Run ()
 		{
+			// Set Continue, because the previous run could clean
+			// this flag by Dispatcher.ExitAllFrames.
+			main_execution_frame.Continue = true;
 			PushFrame (main_execution_frame);
 		}
 		
diff --git a/mcs/class/WindowsBase/Test/System.Windows.Threading/DispatcherTest.cs b/mcs/class/WindowsBase/Test/System.Windows.Threading/DispatcherTest.cs
index 0980ebb12ba..889b10e2e03 100644
--- a/mcs/class/WindowsBase/Test/System.Windows.Threading/DispatcherTest.cs
+++ b/mcs/class/WindowsBase/Test/System.Windows.Threading/DispatcherTest.cs
@@ -155,11 +155,17 @@ namespace MonoTests.System.Windows.Threading
 		{
 			Dispatcher d = Dispatcher.CurrentDispatcher;
 			Action exit = delegate { Dispatcher.ExitAllFrames(); };
+			int counter = 0;
+			Action increment = delegate { counter++; };
 
 			d.BeginInvoke(DispatcherPriority.Normal, exit);
 			Dispatcher.Run();
+			d.BeginInvoke(DispatcherPriority.Normal, increment);
+			d.BeginInvoke(DispatcherPriority.Normal, increment);
 			d.BeginInvoke(DispatcherPriority.Normal, exit);
 			Dispatcher.Run();
+
+			Assert.AreEqual(2, counter, "Counter of delegate invocation");
 		}
 	}
 }