[FancyZones Editor] Fix FZ Editor crash on opening custom layout for editing (#10911)

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

@@ -5,7 +5,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Windows;
 using System.Windows.Controls;
 using FancyZonesEditor.Models;
 
@@ -121,7 +120,7 @@ namespace FancyZonesEditor
 
             if (zoneCount > rows * cols)
             {
-                throw new ArgumentException("Invalid index found in model.CellChildMap");
+                return;
             }
 
             var indexCount = Enumerable.Repeat(0, zoneCount).ToList();
@@ -147,33 +146,18 @@ namespace FancyZonesEditor
             {
                 if (indexCount[index] == 0)
                 {
-                    throw new ArgumentException("Indices in model.CellChildMap are not contiguous");
+                    return;
                 }
 
                 if (indexCount[index] != (indexRowHigh[index] - indexRowLow[index] + 1) * (indexColHigh[index] - indexColLow[index] + 1))
                 {
-                    throw new ArgumentException("One or more indices in model.CellChildMap don't form a rectangle");
+                    return;
                 }
             }
 
-            if (model.RowPercents.Count != rows)
+            if (model.RowPercents.Count != model.Rows || model.ColumnPercents.Count != model.Columns || model.RowPercents.Exists((x) => (x < 1)) || model.ColumnPercents.Exists((x) => (x < 1)))
             {
-                throw new ArgumentException("model.RowPercents has invalid size");
-            }
-
-            if (model.ColumnPercents.Count != cols)
-            {
-                throw new ArgumentException("model.ColumnPercents has invalid size");
-            }
-
-            if (model.RowPercents.Exists((x) => (x < 1)))
-            {
-                throw new ArgumentException("Invalid value in model.RowPercents");
-            }
-
-            if (model.ColumnPercents.Exists((x) => (x < 1)))
-            {
-                throw new ArgumentException("Invalid value in model.ColumnPercents");
+                return;
             }
 
             var rowPrefixSum = PrefixSum(model.RowPercents);
@@ -181,7 +165,7 @@ namespace FancyZonesEditor
 
             if (rowPrefixSum[rows] != Multiplier || colPrefixSum[cols] != Multiplier)
             {
-                throw new ArgumentException();
+                return;
             }
 
             _zones = new List<Zone>(zoneCount);

src/modules/fancyzones/editor/FancyZonesEditor/GridEditor.xaml.cs

@@ -97,7 +97,7 @@ namespace FancyZonesEditor
         {
             Size actualSize = WorkAreaSize();
 
-            if (actualSize.Width < 1 || _data == null || Model == null)
+            if (actualSize.Width < 1 || _data == null || _data.Zones == null || Model == null)
             {
                 return;
             }

src/modules/fancyzones/editor/FancyZonesEditor/Models/GridLayoutModel.cs

@@ -2,6 +2,7 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Collections.Generic;
 
 namespace FancyZonesEditor.Models
@@ -173,6 +174,53 @@ namespace FancyZonesEditor.Models
             }
         }
 
+        public bool IsModelValid()
+        {
+            // Check if rows and columns are valid
+            if (Rows <= 0 || Columns <= 0)
+            {
+                return false;
+            }
+
+            // Check if percentage is valid.
+            if (RowPercents.Count != Rows || ColumnPercents.Count != Columns || RowPercents.Exists((x) => (x < 1)) || ColumnPercents.Exists((x) => (x < 1)))
+            {
+                return false;
+            }
+
+            // Check if cells map is valid
+            if (CellChildMap.Length != Rows * Columns)
+            {
+                return false;
+            }
+
+            int zoneCount = 0;
+            for (int row = 0; row < Rows; row++)
+            {
+                for (int col = 0; col < Columns; col++)
+                {
+                    zoneCount = Math.Max(zoneCount, CellChildMap[row, col]);
+                }
+            }
+
+            zoneCount++;
+
+            if (zoneCount > Rows * Columns)
+            {
+                return false;
+            }
+
+            var rowPrefixSum = GridData.PrefixSum(RowPercents);
+            var colPrefixSum = GridData.PrefixSum(ColumnPercents);
+
+            if (rowPrefixSum[Rows] != GridData.Multiplier || colPrefixSum[Columns] != GridData.Multiplier)
+            {
+                return false;
+            }
+
+            return true;
+        }
+
         public void UpdatePreview()
         {
             FirePropertyChanged();

src/modules/fancyzones/editor/FancyZonesEditor/Utils/FancyZonesEditorIO.cs

@@ -916,17 +916,19 @@ namespace FancyZonesEditor.Utils
             }
 
             // Check if percentage is valid. Otherwise, Editor could crash on layout rendering.
-            foreach (int percent in info.RowsPercentage)
+            if (info.RowsPercentage.Exists((x) => (x < 1)) || info.ColumnsPercentage.Exists((x) => (x < 1)))
             {
-                if (percent < 0)
-                {
-                    return null;
-                }
+                return null;
             }
 
-            foreach (int percent in info.ColumnsPercentage)
+            if (info.CellChildMap.Length != info.Rows)
             {
-                if (percent < 0)
+                return null;
+            }
+
+            foreach (var col in info.CellChildMap)
+            {
+                if (col.Length != info.Columns)
                 {
                     return null;
                 }
@@ -942,6 +944,11 @@ namespace FancyZonesEditor.Utils
             }
 
             var layout = new GridLayoutModel(wrapper.Uuid, wrapper.Name, LayoutType.Custom, info.Rows, info.Columns, info.RowsPercentage, info.ColumnsPercentage, cells);
+            if (!layout.IsModelValid())
+            {
+                return null;
+            }
+
             layout.SensitivityRadius = info.SensitivityRadius;
             layout.ShowSpacing = info.ShowSpacing;
             layout.Spacing = info.Spacing;