Fixes #2326. Invisible cursor after modal dialog.

Terminal.Gui/ConsoleDrivers/WindowsDriver.cs

@@ -116,6 +116,10 @@ public void SetInitialCursorVisibility ()
 
 		public bool GetCursorVisibility (out CursorVisibility visibility)
 		{
+			if (ScreenBuffer == IntPtr.Zero) {
+				visibility = CursorVisibility.Invisible;
+				return false;
+			}
 			if (!GetConsoleCursorInfo (ScreenBuffer, out ConsoleCursorInfo info)) {
 				var err = Marshal.GetLastWin32Error ();
 				if (err != 0) {

Terminal.Gui/Core/Application.cs

@@ -940,6 +940,8 @@ public static RunState Begin (Toplevel toplevel)
 				if (Top != null && toplevel != Top && !toplevels.Contains (Top)) {
 					Top.Dispose ();
 					Top = null;
+				} else if (Top != null && toplevel != Top && toplevels.Contains (Top)) {
+					Top.OnLeave (toplevel);
 				}
 				if (string.IsNullOrEmpty (toplevel.Id.ToString ())) {
 					var count = 1;
@@ -1048,6 +1050,7 @@ public static void End (RunState runState)
 					MdiTop.OnAllChildClosed ();
 				} else {
 					SetCurrentAsTop ();
+					Current.OnEnter (Current);
 				}
 				Refresh ();
 			}

Terminal.Gui/Core/Toplevel.cs

@@ -959,6 +959,18 @@ public virtual bool ShowChild (Toplevel top = null)
 			}
 			return false;
 		}
+
+		///<inheritdoc/>
+		public override bool OnEnter (View view)
+		{
+			return MostFocused?.OnEnter (view) ?? base.OnEnter (view);
+		}
+
+		///<inheritdoc/>
+		public override bool OnLeave (View view)
+		{
+			return MostFocused?.OnLeave (view) ?? base.OnLeave (view);
+		}
 	}
 
 	/// <summary>

Terminal.Gui/Views/TextView.cs

@@ -2035,6 +2035,16 @@ public override bool OnEnter (View view)
 			return base.OnEnter (view);
 		}
 
+		///<inheritdoc/>
+		public override bool OnLeave (View view)
+		{
+			if (Application.MouseGrabView != null && Application.MouseGrabView == this) {
+				Application.UngrabMouse ();
+			}
+
+			return base.OnLeave (view);
+		}
+
 		// Returns an encoded region start..end (top 32 bits are the row, low32 the column)
 		void GetEncodedRegionBounds (out long start, out long end,
 			int? startRow = null, int? startCol = null, int? cRow = null, int? cCol = null)
@@ -4447,16 +4457,6 @@ void ProcessMouseClick (MouseEvent ev, out List<Rune> line)
 			line = r;
 		}
 
-		///<inheritdoc/>
-		public override bool OnLeave (View view)
-		{
-			if (Application.MouseGrabView != null && Application.MouseGrabView == this) {
-				Application.UngrabMouse ();
-			}
-
-			return base.OnLeave (view);
-		}
-
 		/// <summary>
 		/// Allows clearing the <see cref="HistoryText.HistoryTextItem"/> items updating the original text.
 		/// </summary>

UnitTests/TopLevels/ToplevelTests.cs

@@ -696,7 +696,7 @@ public void Mouse_Drag_On_Top_With_Superview_Null ()
 					((FakeDriver)Application.Driver).SetBufferSize (40, 15);
 					MessageBox.Query ("About", "Hello Word", "Ok");
 
-				} else if (iterations == 1) 					TestHelpers.AssertDriverContentsWithFrameAre (@"
+				} else if (iterations == 1) TestHelpers.AssertDriverContentsWithFrameAre (@"
  File                                   
 ┌ Window ──────────────────────────────┐
 │                                      │
@@ -712,7 +712,7 @@ public void Mouse_Drag_On_Top_With_Superview_Null ()
 │                                      │
 └──────────────────────────────────────┘
  CTRL-N New                             ", output);
-else if (iterations == 2) {
+				else if (iterations == 2) {
 					Assert.Null (Application.MouseGrabView);
 					// Grab the mouse
 					ReflectionTools.InvokePrivate (
@@ -815,8 +815,8 @@ public void Mouse_Drag_On_Top_With_Superview_Null ()
 
 					Assert.Null (Application.MouseGrabView);
 
-				} else if (iterations == 8) 					Application.RequestStop ();
-else if (iterations == 9) 					Application.RequestStop ();
+				} else if (iterations == 8) Application.RequestStop ();
+				else if (iterations == 9) Application.RequestStop ();
 			};
 
 			Application.Run ();
@@ -956,7 +956,7 @@ public void Mouse_Drag_On_Top_With_Superview_Not_Null ()
 
 					Assert.Null (Application.MouseGrabView);
 
-				} else if (iterations == 8) 					Application.RequestStop ();
+				} else if (iterations == 8) Application.RequestStop ();
 			};
 
 			Application.Run ();
@@ -974,5 +974,42 @@ public void EnsureVisibleBounds_With_Border_Null_Not_Throws ()
 			exception = Record.Exception (() => ((FakeDriver)Application.Driver).SetBufferSize (10, 0));
 			Assert.Null (exception);
 		}
+
+		[Fact, AutoInitShutdown]
+		public void OnEnter_OnLeave_Triggered_On_Application_Begin_End ()
+		{
+			var isEnter = false;
+			var isLeave = false;
+			var v = new View ();
+			v.Enter += (_) => isEnter = true;
+			v.Leave += (_) => isLeave = true;
+			var top = Application.Top;
+			top.Add (v);
+
+			Assert.False (v.CanFocus);
+			var exception = Record.Exception (() => top.OnEnter (top));
+			Assert.Null (exception);
+			exception = Record.Exception (() => top.OnLeave (top));
+			Assert.Null (exception);
+
+			v.CanFocus = true;
+			Application.Begin (top);
+
+			Assert.True (isEnter);
+			Assert.False (isLeave);
+
+			isEnter = false;
+			var d = new Dialog ();
+			var rs = Application.Begin (d);
+
+			Assert.False (isEnter);
+			Assert.True (isLeave);
+
+			isLeave = false;
+			Application.End (rs);
+
+			Assert.True (isEnter);
+			Assert.False (isLeave);
+		}
 	}
 }