Merge pull request #1010 from mbm-OR/bugfix/Fix-TrainDrivingInfo-window-width-not-stable

Fix: TrainDrivingInfo window width not stable.

Author: mbm-OR

Source/RunActivity/Viewer3D/Popups/TrainDrivingWindow.cs

@@ -227,6 +227,7 @@ private static class Symbols
 
         public bool normalTextMode = true;// Standard text
         public bool TrainDrivingUpdating = false;
+        public int CurrentWidth = 0;
         public static bool MonoFont;
         public static bool FontChanged;
         public static bool FontToBold;
@@ -489,6 +490,15 @@ private void ModifyWindowSize()
                 var newHeight = (int)MathHelper.Clamp(desiredHeight, (normalTextMode ? WindowHeightMin : 100), WindowHeightMax);
                 var newWidth = (int)MathHelper.Clamp(desiredWidth, (normalTextMode ? WindowWidthMin : 100), WindowWidthMax);
 
+                // Stable window width
+                if (normalTextMode) CurrentWidth = 0;// Reset CurrentWidth value
+                if (!normalTextMode && newWidth != CurrentWidth)
+                {
+                    var newWidthHigher = newWidth > CurrentWidth;
+                    newWidth = newWidthHigher ? newWidth : CurrentWidth;
+                    CurrentWidth = newWidthHigher ? newWidth : CurrentWidth;
+                }
+
                 // Move the dialog up if we're expanding it, or down if not; this keeps the center in the same place.
                 var newTop = Location.Y + (Location.Height - newHeight) / 2;