Escape key now brings up a dialog to confirm you want to stop emulation (#1044)

* Add a dialog to make sure user wants to stop emulation when esc is pressed

* Remove unneccesary space

* Fix formatting

* Remove unnessecary spaces

* Fix formatting for member of GtkDialog

Ryujinx/Ui/GLRenderer.cs

@@ -137,9 +137,12 @@ namespace Ryujinx.Ui
                     else
                     {
                         if (keyboard.IsKeyDown(OpenTK.Input.Key.Escape))
+                        {
+                            if (GtkDialog.CreateExitDialog())
                             {
                                 Exit();
                             }
+                        }
                         else
                         {
                             ParentWindow.Fullscreen();

Ryujinx/Ui/GtkDialog.cs

@@ -5,6 +5,8 @@ namespace Ryujinx.Ui
 {
     internal class GtkDialog
     {
+        internal static bool _isExitDialogOpen = false;
+
         internal static void CreateDialog(string title, string text, string secondaryText)
         {
             MessageDialog errorDialog = new MessageDialog(null, DialogFlags.Modal, MessageType.Error, ButtonsType.Ok, null)
@@ -29,5 +31,36 @@ namespace Ryujinx.Ui
         {
             CreateDialog("Ryujinx - Error", "Ryujinx has encountered an error", errorMessage);
         }
+
+        internal static bool CreateExitDialog()
+        {
+            if (_isExitDialogOpen)
+            {
+                return false;
+            }
+
+            _isExitDialogOpen = true;
+
+            MessageDialog messageDialog = new MessageDialog(null, DialogFlags.Modal, MessageType.Question, ButtonsType.OkCancel, null)
+            {
+                Title = "Ryujinx - Exit",
+                Icon = new Gdk.Pixbuf(Assembly.GetExecutingAssembly(), "Ryujinx.Ui.assets.Icon.png"),
+                Text = "Are you sure you want to stop emulation?",
+                SecondaryText = "All unsaved data will be lost",
+                WindowPosition = WindowPosition.Center
+            };
+
+            messageDialog.SetSizeRequest(100, 20);
+            ResponseType res = (ResponseType)messageDialog.Run();
+            messageDialog.Dispose();
+            _isExitDialogOpen = false;
+            
+            if (res == ResponseType.Ok)
+            {
+                return true;
+            } 
+            
+            return false;
+        }
     }
 }