[FancyZones Editor] New UX for the FZ editor. (#9325)

* Removed MetroWindow, added theming support and modernWPF

* Rmoved MahApps refs

* Removed MahApps

* Updated canvas zones

* Updated GridEditor

* Fixes

* UI updates

* New layout type selection dialog

* New editor UI

* Updates

* Fix

* UI enhancements

* Updated UI

* Added styles to layoutpreview

* Accesibility improvements

* Accesibility and styling improvements

* Fix

* Cleaned up brushes

* Updated UX

* Updated UI

* Added no layouts description

* Fix

* UI fixes

* [FZ Editor] Serialize/deserialize settings (#8615)

* conflicts fix

* [FZ Editor] Parse json file instead of command line args (#8649)

* [FZ Editor] Serialize/deserialize settings fix (#8707)

* [FZ Editor] Hide unsupported settings in custom layouts flyouts (#8716)

* [FZ Editor] Duplicate custom layouts (#8718)

* [FZ Editor] Duplicate layout behavior (#8720)

* New UX proposal

* Updated spacing

* Switching to toggleswitches

* Revert toggleswitch

* Updated colorbrush

* Updated string for saving label

* Updated UI

* Dark theme color fixes

* Removed space

* [FZ Editor] Bind dialog properties (#9199)

* Resize editor window to fit the content in single-monitor mode (#9203)

* Editor opening fix (#9207)

* Disable "Create" button if the Name textbox is empty (#9212)

* [FZ Editor] Changed edit dialog for template layouts. (#9233)

* [FZ Editor] Small fixes and refactoring. (#9236)

* new layout creation refactoring
* "Save and apply" applies the layout
* number of zones header hide

* [FZ Editor] Empty layout template. (#9237)

* [FZ Editor] Move "Duplicate" and "Delete" buttons to the Edit dialog. (#9272)

* [FZ Editor] Preview the applied layout after editing another layout. (#9278)

* Fixed "Save and apply" button behavior (#9286)

* [FZ Editor] Save template layouts in the settings. (#9283)

* Added default custom layout name (#9291)

* close dialog before opening zones editor (#9302)

* Pressing Esc closes dialogs (#9301)

* [FZ Editor] Reset applied layout to "No layout" if it was deleted. (#9315)

* [FZ Editor] Dark theme colors (#9317)

* "Number of zones" buttons colors. (#9321)

* rebase fix

* added ModernWpf.dll

* address PR comments: updated colors

* added comments, replaced magic numbers

* refactoring

* merge zones crash fix

* removed redundant using directive

Co-authored-by: Niels Laute <niels9001@hotmail.com>
Co-authored-by: Niels Laute <niels.laute@live.nl>

src/modules/fancyzones/editor/FancyZonesEditor/GridData.cs

@@ -7,7 +7,6 @@ using System.Collections.Generic;
 using System.Windows;
 using System.Windows.Controls;
 using FancyZonesEditor.Models;
-using FancyZonesEditor.Utils;
 
 namespace FancyZonesEditor
 {
@@ -120,25 +119,29 @@ namespace FancyZonesEditor
             {
                 _colInfo.Add(new RowColInfo(model.ColumnPercents[col]));
             }
+
+            int maxIndex = 0;
+            for (int row = 0; row < _model.Rows; row++)
+            {
+                for (int col = 0; col < _model.Columns; col++)
+                {
+                    maxIndex = Math.Max(maxIndex, _model.CellChildMap[row, col]);
+                }
+            }
+
+            _zoneCount = maxIndex + 1;
         }
 
         public int ZoneCount
         {
             get
             {
-                int maxIndex = 0;
-                for (int row = 0; row < _model.Rows; row++)
-                {
-                    for (int col = 0; col < _model.Columns; col++)
-                    {
-                        maxIndex = Math.Max(maxIndex, _model.CellChildMap[row, col]);
-                    }
-                }
-
-                return maxIndex;
+                return _zoneCount;
             }
         }
 
+        private int _zoneCount;
+
         public Tuple<int, int> RowColByIndex(int index)
         {
             int foundRow = -1;
@@ -238,6 +241,7 @@ namespace FancyZonesEditor
             FixAccuracyError(_colInfo, _model.ColumnPercents);
             _model.CellChildMap = newCellChildMap;
             _model.Columns++;
+            _model.UpdatePreview();
         }
 
         public void SplitRow(int foundRow, int spliteeIndex, int newChildIndex, double space, double offset, double actualHeight)
@@ -289,6 +293,7 @@ namespace FancyZonesEditor
             FixAccuracyError(_rowInfo, _model.RowPercents);
             _model.CellChildMap = newCellChildMap;
             _model.Rows++;
+            _model.UpdatePreview();
         }
 
         public void SplitOnDrag(GridResizer resizer, double delta, double space)
@@ -447,6 +452,8 @@ namespace FancyZonesEditor
                 _model.CellChildMap = newCellChildMap;
                 _model.Rows++;
             }
+
+            _model.UpdatePreview();
         }
 
         public void RecalculateZones(int spacing, Size arrangeSize)
@@ -474,6 +481,11 @@ namespace FancyZonesEditor
 
         public void ArrangeZones(UIElementCollection zones, int spacing)
         {
+            if (zones.Count == 0)
+            {
+                return;
+            }
+
             int rows = _model.Rows;
             int cols = _model.Columns;
             int[,] cells = _model.CellChildMap;
@@ -1029,6 +1041,7 @@ namespace FancyZonesEditor
 
             _model.Rows = rows;
             _model.Columns = cols;
+            _model.UpdatePreview();
         }
 
         private void FixAccuracyError(List<RowColInfo> info, List<int> percents)