Fixes U4-2702 Ensure the new file uploader has consistent pre-values pre previous versions

src/Umbraco.Web/PropertyEditors/ColorListPreValueEditor.cs

@@ -11,14 +11,19 @@ namespace Umbraco.Web.PropertyEditors
 {
     internal class ColorListPreValueEditor : ValueListPreValueEditor
     {
+      
         public ColorListPreValueEditor()
         {
+            var field = Fields.First();
+
             //use a custom editor too
-            Fields.First().View = "views/propertyeditors/colorpicker/colorpicker.prevalues.html";
+            field.View = "views/propertyeditors/colorpicker/colorpicker.prevalues.html";
             //change the description
-            Fields.First().Description = "Add and remove colors in HEX format without a prefixed '#'";
+            field.Description = "Add and remove colors in HEX format without a prefixed '#'";
+            //change the label
+            field.Name = "Add color";
             //need to have some custom validation happening here
-            Fields.First().Validators.Add(new ColorListValidator());
+            field.Validators.Add(new ColorListValidator());
         }
 
         internal class ColorListValidator : IPropertyValidator

src/Umbraco.Web/PropertyEditors/FileUploadPropertyEditor.cs

@@ -1,8 +1,11 @@
 using System;
 using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
 using System.Drawing;
 using System.Linq;
+using System.Text.RegularExpressions;
 using System.Xml;
+using Newtonsoft.Json.Linq;
 using Umbraco.Core;
 using Umbraco.Core.Configuration;
 using Umbraco.Core.Configuration.UmbracoSettings;
@@ -126,6 +129,16 @@ namespace Umbraco.Web.PropertyEditors
         /// </summary>
         internal class FileUploadPreValueEditor : ValueListPreValueEditor
         {
+            public FileUploadPreValueEditor()
+                : base()
+            {
+                var field = Fields.First();
+                field.Description = "Enter a max width/height for each thumbnail";
+                field.Name = "Add thumbnail size";
+                //need to have some custom validation happening here
+                field.Validators.Add(new ThumbnailListValidator());
+            }
+
             /// <summary>
             /// Format the persisted value to work with our multi-val editor.
             /// </summary>
@@ -164,12 +177,43 @@ namespace Umbraco.Web.PropertyEditors
 
                 //this should just be a dictionary of values, we want to re-format this so that it is just one value in the dictionary that is 
                 // semi-colon delimited
-                var values = result.Select(item => item.Value).ToList();
+                var values = result.Select(item => item.Value.Value).ToList();
 
                 result.Clear();
                 result.Add("thumbs", new PreValue(string.Join(";", values)));
                 return result;
             }
+
+            internal class ThumbnailListValidator : IPropertyValidator
+            {
+                public IEnumerable<ValidationResult> Validate(object value, PreValueCollection preValues, PropertyEditor editor)
+                {
+                    var json = value as JArray;
+                    if (json == null) yield break;
+
+                    //validate each item which is a json object
+                    for (var index = 0; index < json.Count; index++)
+                    {
+                        var i = json[index];
+                        var jItem = i as JObject;
+                        if (jItem == null || jItem["value"] == null) continue;
+
+                        //NOTE: we will be removing empty values when persisting so no need to validate
+                        var asString = jItem["value"].ToString();
+                        if (asString.IsNullOrWhiteSpace()) continue;
+
+                        int parsed;
+                        if (int.TryParse(asString, out parsed) == false)
+                        {
+                            yield return new ValidationResult("The value " + asString + " is not a valid number", new[]
+                            {
+                                //we'll make the server field the index number of the value so it can be wired up to the view
+                                "item_" + index.ToInvariantString()
+                            });   
+                        }
+                    }
+                }
+            }
         }
 
     }