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Why won't checkmarks appear in an TreeListView checkbox when CheckedAspectName name is set (and how do I programmatically set checkboxes)?

My question is based on the ObjectListView gettingstarted code (GettingStartedTree project ) referred to in the Getting Started section of the ObjectListView sourceforge online docs.
My goal is to add checkboxes to the Title column of the TreeListView in the GettingStartedTree project.
I was able to add checkboxes simply by setting treeListView1.CheckBoxes to true and setting treeListView1.CheckedAspectName to Title (see After making changes below) as described in the instructions. Problem: However, when I run the program and click on a checkbox, a checkmark does not appear in the checkbox. I expect that a user should be able to "check" a checkbox on the UI.
Note: If I leave treeListView1.CheckBoxes set to true and set treeListView1.CheckedAspectName to null, then a checkmark does appear in the checkbox.
Am I configuring the TreeListView correctly?
Before making any changes
treeListView1:
CheckBoxes = false
CheckedAspectName = null
OLVColumn Collection, olvColumn1(Title):
Name = olvColumn1
AspectName = Title
CheckBoxes = false (Title column)
After making changes
treeListView1:
CheckBoxes = true
CheckedAspectName = Title
OLVColumn Collection, olvColumn1(Title):
Name = olvColumn1
AspectName = Title
CheckBoxes = false (Title column)

HierarchicalCheckboxes doesn't work with CheckedAspectName (or CheckedAspectGetter), although finding the documentation on this isn't easy.
Some additional information here:
Hierarchy-aware checkboxes

Just to make this clear...
To enable checkboxes for the TreeListView (or any other version of ObjectListView), just set CheckBoxes to true on the control itself.
That's all you need to do.
If you have a property on your model that indicates whether a row should be checked or not, you can automatically hook that value onto the checkboxes by setting CheckedAspectName to the name of that property. For example, if your model has an IsSelected property, then this will hook the checkbox to that property:
treeListView1.CheckedAspectName = "IsSelected";
The type of that property must be bool (or bool? if you have a tri-state check box). So, in the question, setting the CheckedAspectName to "Title" cannot work because Title is not a boolean.
Don't change any value in any column to get checkboxes to work.
If you are using hierarchical checkboxes, you can't use CheckedAspectName or anything else that eventually installs a CheckStateGetter. The docs on the Hierarchy-aware checkboxes page that Patrick mentioned explain why.

Update
After posting this answer, I came across a TreeViewList property
named HierarchicalCheckboxes that I hadn't noticed before and that I
don't see discussed/described anywhere in the ObjectListView
sourceforge docs. I now believe this is what Grammarian was referring
to in his comment under Patricks answer. In my code (in this answer),
this property is set false, so I assume I'm NOT using
HierarchicalCheckboxes. I thought hierarchical checkboxes were checkboxes in a model that has a hierarchical structure like the model in my code in this answer.
I guess/assume HierarchicalCheckboxes is
associated with the write-up on Hierarchy-aware checkboxes ,
although I'm not sure. ObjectListView is a great control. I just wish the ObjectListView sourceforge docs did a better job differentiating the explaining the collection of lists required to draw the treeview portion of a TreeListView along with adding and managing checkboxes to such a model both with with and without the use of the hierarchical checkboxes feature (enabled by the property HierarchicalCheckboxes). I guess all the pieces are in the docs, but its spread out and a bit disjointed.
End of Update
For the sake of clarity I was kind of forced to answer this myself.....
Reminder: all this is based on the gettingstartedcode described in the original question.
First, the answer to my initial problem was to clear treeview1.CheckedAspectName as in the original example code. Doing so resulted in a checkmark appearing in the checkbox (as expected) when the checkbox is clicked.
Grammarian kindly described how to programmatically check/uncheck a checkbox for (I assume) a non-hierarchical checkbox scenario, i.e., add a bool? or bool property to the model and add the property's name to the TreeListView's CheckedAspectName property.
I came to the conclusion that this won't work for hierarchical checkboxes because Grammarian said the following and loading the bool? or bool property's name into CheckedAspectName is required based on his explanation.
If you are using hierarchical checkboxes, you can't use
CheckedAspectName or anything else that eventually installs a
CheckStateGetter
So, ignoring the advice that setting the CheckedAspectName property for hierarchical checkboxes won't work, I implemented a bool? isChecked property at all levels in my hierarchical model. It works fine, i.e., I can now programmatically check a checkbox at any level in the hierarchy via the model.
Code for a simple example follows (I need to write the code to set the tri-state checkbox for parent rows based on the checkedness or uncheckedness of child rows.). The column "# To Keep" is designed to be relevant only for the level-2 items in the hierarchy
The form has only a FooTreeListView : BrightIdeasSoftware.TreeListView control on it
FooTreeListView.cs
using System;
using System.Collections.Generic;
namespace ObjectListView_TreeListView
{
class FooTreeListView : BrightIdeasSoftware.TreeListView
{
private List<Categories> categoriesList;
private readonly string[] categoryDescriptors = { "Cat A", "Cat B", "Cat C", "Cat D" };
internal List<Categories> CategoriesList { get => categoriesList; set => categoriesList = value; }
public enum CategoryEnum
{
CategoryA = 0,
CategoryB = 1,
CategoryC = 2,
CategoryD = 3
}
public FooTreeListView() : base()
{
CategoriesList = new List<Categories>();
CategoriesList.Clear();
CanExpandGetter = delegate (Object x)
{
if (x is Categories && ((Categories)x).ItemList.Count > 0)
{
return true;
}
if (x is Categories.Item && ((Categories.Item)x).ActionList.Count > 0)
{return true;
}
return false;
};
ChildrenGetter = delegate (Object x)
{
if (x is Categories)
return ((Categories)x).ItemList;
if (x is Categories.Item)
return ((Categories.Item)x).ActionList;
throw new ArgumentException("Should be Categories or Categories.Item");
};
//Load the 4 top-level categories into the tree
CategoriesList.Add(new Categories(categoryDescriptors[(int)CategoryEnum.CategoryA],false));
CategoriesList.Add(new Categories(categoryDescriptors[(int)CategoryEnum.CategoryB], false));
CategoriesList.Add(new Categories(categoryDescriptors[(int)CategoryEnum.CategoryC], false));
CategoriesList.Add(new Categories(categoryDescriptors[(int)CategoryEnum.CategoryD], false));
}
internal class Categories
{
private string action;
private bool? isChecked;
public string Action { get { return action; } set { action = value; } }
public bool? IsChecked { get => isChecked; set => isChecked = value; }
private List<Item> itemList;
internal List<Item> ItemList { get => itemList; set => itemList = value; }
public Categories(string action, bool? isChecked)
{
this.action = action;
this.isChecked = isChecked;
ItemList = new List<Item>();
}
internal class Item
{
private string action;
private bool? isChecked;
private int numberToKeep = 0;
private List<ItemAction> actionList;
public string Action { get { return action; } set { action = value; } }
public int NumberToKeep { get => numberToKeep; set => numberToKeep = value; }
public bool? IsChecked { get => isChecked; set => isChecked = value; }
internal List<ItemAction> ActionList { get => actionList; set => actionList = value; }
internal Item(string action, bool? isChecked, int numberToKeep)
{
this.action = action;
this.isChecked = isChecked;
this.NumberToKeep = numberToKeep;
ActionList = new List<ItemAction>();
}
internal class ItemAction
{
private string action;
private bool? isChecked;
public string Action { get { return action; } set { action = value; } }
public bool? IsChecked { get { return isChecked; } set { isChecked = value; } }
internal ItemAction(string action, bool? isChecked)
{
this.action = action;
this.isChecked = isChecked;
}
}
}
}
public void AddCategoryItemName(CategoryEnum category, string itemName, bool? isChecked, int numberToKeep)
{
CategoriesList[(int)category].ItemList.Add(new Categories.Item(itemName, isChecked, numberToKeep));
}
public void AddItemAction(CategoryEnum category, string itemName, string action, Boolean isChecked)
{
Categories.Item itemMatch = CategoriesList[(int)category].ItemList.Find(x => x.Action.Equals(itemName));
if (itemMatch != null)
{
itemMatch.ActionList.Add(new Categories.Item.ItemAction(action, isChecked));
}
else
{
throw new ArgumentException(String.Format("Can't find treeviewlist item '{0}'->'{1}'", categoryDescriptors[(int)category], itemName));
}
}
public void AddItemAction(CategoryEnum category, string itemName, string action)
{
Categories.Item itemMatch = CategoriesList[(int)category].ItemList.Find(x => x.Action.Equals(itemName));
if (itemMatch != null)
{
itemMatch.ActionList.Add(new Categories.Item.ItemAction(action, false));
}
else
{
throw new ArgumentException(String.Format("Can't find treeviewlist item '{0}'->'{1}'", categoryDescriptors[(int)category], itemName));
}
}
public void LoadTree()
{
Roots = CategoriesList;
ExpandAll();
}
}
}
Form1.cs
using System.Windows.Forms;
using static ObjectListView_TreeListView.FooTreeListView;
namespace ObjectListView_TreeListView
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
SuspendLayout();
xenSnapshotsTreeListView1.AddCategoryItemName(CategoryEnum.CategoryA, "Item A", true, 0);
xenSnapshotsTreeListView1.AddCategoryItemName(CategoryEnum.CategoryA, "Item B", false, 1);
xenSnapshotsTreeListView1.AddItemAction(CategoryEnum.CategoryA, "Item A", "Item A foo", true);
xenSnapshotsTreeListView1.AddItemAction(CategoryEnum.CategoryA, "Item A", "Item A bar", false);
xenSnapshotsTreeListView1.AddItemAction(CategoryEnum.CategoryA, "Item B", "Item B foo");
xenSnapshotsTreeListView1.AddItemAction(CategoryEnum.CategoryA, "Item B", "Item B bar", true);
xenSnapshotsTreeListView1.LoadTree();
ResumeLayout();
}
}
}
Form1.Designer.cs
namespace ObjectListView_TreeListView
{
partial class Form1
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.xenSnapshotsTreeListView1 = new ObjectListView_TreeListView.FooTreeListView();
this.olvColumnAction = ((BrightIdeasSoftware.OLVColumn)(new BrightIdeasSoftware.OLVColumn()));
this.olvColumnNumbSsToKeep = ((BrightIdeasSoftware.OLVColumn)(new BrightIdeasSoftware.OLVColumn()));
((System.ComponentModel.ISupportInitialize)(this.xenSnapshotsTreeListView1)).BeginInit();
this.SuspendLayout();
//
// xenSnapshotsTreeListView1
//
this.xenSnapshotsTreeListView1.AllColumns.Add(this.olvColumnAction);
this.xenSnapshotsTreeListView1.AllColumns.Add(this.olvColumnNumbSsToKeep);
this.xenSnapshotsTreeListView1.CellEditUseWholeCell = false;
this.xenSnapshotsTreeListView1.CheckBoxes = true;
this.xenSnapshotsTreeListView1.CheckedAspectName = "IsChecked";
this.xenSnapshotsTreeListView1.Columns.AddRange(new System.Windows.Forms.ColumnHeader[] {
this.olvColumnAction,
this.olvColumnNumbSsToKeep});
this.xenSnapshotsTreeListView1.Cursor = System.Windows.Forms.Cursors.Default;
this.xenSnapshotsTreeListView1.Dock = System.Windows.Forms.DockStyle.Fill;
this.xenSnapshotsTreeListView1.GridLines = true;
this.xenSnapshotsTreeListView1.Location = new System.Drawing.Point(0, 0);
this.xenSnapshotsTreeListView1.MultiSelect = false;
this.xenSnapshotsTreeListView1.Name = "xenSnapshotsTreeListView1";
this.xenSnapshotsTreeListView1.ShowGroups = false;
this.xenSnapshotsTreeListView1.ShowImagesOnSubItems = true;
this.xenSnapshotsTreeListView1.Size = new System.Drawing.Size(800, 450);
this.xenSnapshotsTreeListView1.TabIndex = 0;
this.xenSnapshotsTreeListView1.UseAlternatingBackColors = true;
this.xenSnapshotsTreeListView1.UseCompatibleStateImageBehavior = false;
this.xenSnapshotsTreeListView1.View = System.Windows.Forms.View.Details;
this.xenSnapshotsTreeListView1.VirtualMode = true;
//
// olvColumnAction
//
this.olvColumnAction.AspectName = "Action";
this.olvColumnAction.Text = "Action";
this.olvColumnAction.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
this.olvColumnAction.Width = 200;
//
// olvColumnNumbSsToKeep
//
this.olvColumnNumbSsToKeep.AspectName = "NumberToKeep";
this.olvColumnNumbSsToKeep.Text = "# To Keep";
this.olvColumnNumbSsToKeep.TextAlign = System.Windows.Forms.HorizontalAlignment.Right;
this.olvColumnNumbSsToKeep.Width = 65;
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(800, 450);
this.Controls.Add(this.xenSnapshotsTreeListView1);
this.Name = "Form1";
this.Text = "Form1";
((System.ComponentModel.ISupportInitialize)(this.xenSnapshotsTreeListView1)).EndInit();
this.ResumeLayout(false);
}
#endregion
private FooTreeListView xenSnapshotsTreeListView1;
private BrightIdeasSoftware.OLVColumn olvColumnAction;
private BrightIdeasSoftware.OLVColumn olvColumnNumbSsToKeep;
}
}

Adding a bool for each property

I'm building a c# class that works with two different data sources. It will load a data source and take a configuration set from a function. Then I want to do several tasks on all properties within the object.
for example.
public String StreetAddress
{
get { return _streetAddress; }
set
{
if (value.Length <= 64)
_streetAddress = value;
else
_streetAddress = value.Substring(0, 1024).Trim();
}
}
public String City
{
get { return _city; }
set
{
if (value.Length <= 128)
_city = value;
else
_city = value.Substring(0, 128).Trim();
}
}
public String State
{
get { return _state; }
set
{
if (value.Length <= 128)
_state = value;
else
_state = value.Substring(0, 128).Trim();
}
}
So that holds the data from one side. I was hoping to be able to store and set a change flag on each property. So if we take State for example. If the person is moved from Texas to Illinois I want to set a bool within that property to note the change then be able to loop over all changes before saving the object to the DB. But I don't see any way to assign another state variable within that property. Is the best way to write another object on top of this to control it or is there another more creative way to store multiple strings within the one property?

If you'd like an OOP way of doing the thing, you can:
Define an interface and a class for holding your property, such as:
interface IPropertySlot
{
bool IsDirty { get; }
void ResetIsDirty();
object UntypedValue { get; }
}
class PropertySlot<T>:IPropertySlot
{
public T Value { get; private set; }
public bool SetValue(T value)
{
if (!Equals(_value, Value))
{
Value = value;
IsDirty = true;
return true;
}
return false;
}
public bool IsDirty { get; private set; }
public void ResetIsDirty()
{
IsDirty = false;
}
public object UntypedValue
{
get { return Value; }
}
}
Store your properties inside your class in a dictionary from String (for name of property) to IPropertySlot and get/set them through a pair of methods:
void SetProperty<T>(string name, T value)
{
IPropertySlot property;
if (!_properties.TryGetValue(name, out property))
{
property = new PropertySlot<T>();
_properties[name] = property;
}
((PropertySlot<T>)property) .SetValue(value);
}
T GetProperty<T>(string name)
{
IPropertySlot property;
if (!_properties.TryGetValue(name, out property))
{
property = new PropertySlot<T>();
_properties[name] = property;
}
return ((PropertySlot<T>)property).Value;
}
Finding the changed properties later is just a matter of going over the _properties.Values and finding which of them are IsDirty.
This approach also gives you a way to add more functionality to your properties in an OO manner (such as raising PropertyChanged/PropertyChanging events, mapping it to DB fields, etc.).

In such a situation I'd prefer an approach external to the Dto implementation.
Implement some unit that would take two instances of a class, and determine all the differences.
Map each property to compare:
static PropertyManager<Dto> manager = new PropertyManager<Dto>()
.Map(x => x.City)
.Map(x => x.StreetAddress);
Use two instances to compute difference:
var a = new Dto{ StreetAddress = "Foo", City = "Bar" };
var b = new Dto{ StreetAddress = "Foo", City = "Baz" };
var differences = manager.ComputeDifferences(a,b).ToList();
if( differences.Any() )
{
Console.WriteLine("Instances differ");
}
foreach (var diff in differences)
{
Console.WriteLine(diff);
}
This sample code prints out:
Instances differ
x.City
Here is a complete code example:
https://dotnetfiddle.net/4sNeoN

Databound Listview not refreshing when set up with Parallel.Invoke

I have a Window with a TabControl in it. The TabControl contains 5 different TabItems. Each TabItem has its own ViewModel associated as its DataContext, while the Window has a DataContext that has all 5 TabItem's view models as properties. The problem I am having is setup. There is a noticeable lag when I launch the Window (from my MainWindow) and I have spent a good chunk of time refactoring my code and making it faster by running things in parallel, making fewer calls to the database and running Tasks on semi-expensive operations. Everything works great, except for one TabItem and its view model. For some reason, the view does not refresh itself properly.
For instance, I have a view model called DiaryDescriptionViewModel that takes in List<SectionViewModel> and does stuff with it, with the view bound to a result collection. It works fine. My troublesome view model is called DiaryPayItemEditorViewModel and it too takes in a List<SectionViewModel> and does stuff with it, with the view bound to a result collection. Neither view models perform the work on List<SectionViewModel> on worker threads or anything. However both view models are instanced and set up in parallel, which I wouldn't think be the root of the problem.
In my DiaryPayItemEditorViewModel, I have a ObservableCollection<DiaryPayItemDetailViewModel> that a ListView is data bound to. The ListView never displays the data, even though it exists. If I take all of my view model initialization code out of a Parallel.Invoke call, then it binds and displays the data.
My assumption here is that the view is initialized (this.InitializeComponents) before the DiaryPayItemEditorViewModel is fully set up, which should be fine. Since my view models all implement INotifyPropertyChanged, the view should be notified that changes have taken place. For the life of me, I can't figure this out.
The following is the applicable source for the view Window view model (DiaryEditorViewModel), the view model who uses the same collection and works with binding (DiaryDescriptionViewModel and its child DiaryDescriptionDetailsViewModel) and then my troublesome view model (DiaryPayItemEditorViewModel and its child DiaryPayItemDetailViewModel).
DiaryEditorViewModel.cs
public class DiaryEditorViewModel : BaseChangeNotify
{
private DiaryViewModel diary;
private Project project;
private DiaryDetailsViewModel diaryDetailsViewModel;
private DiaryDescriptionViewModel diaryDescriptionViewModel;
private DiaryPayItemEditorViewModel diaryPayItemsViewModel;
private DiaryEquipmentEditorViewModel diaryEquipmentEditorViewModel;
private DiaryLaborViewModel diaryLaborViewModel;
// This is the designated constructor used by the app.
public DiaryEditorViewModel(Project project, Diary diary, UserViewModel user)
: base(user)
{
// Instance a new diary view model using the provided diary.
this.diary = new DiaryViewModel(diary, user);
this.project = project;
// Setup the repositories we will use.
var repository = new ProjectRepository();
var contractorRepository = new ContractorRepository();
// Setup the temporary collections used by the repositories.
var contractors = new List<Contractor>();
var contractorViewModels = new List<ContractorViewModel>();
var projectSections = new List<Section>();
var bidItemCollection = new List<BidItem>();
var subItemCollection = new List<SubItem>();
var sectionViewModels = new List<SectionViewModel>();
var equipmentCategories = new List<EquipmentCategory>();
var equipmentFuelTypes = new List<EquipmentFuelType>();
var equipmentList = new List<Equipment>();
var equipmentViewModels = new List<EquipmentViewModel>();
Task.Run(() =>
{
Parallel.Invoke(
// Fetch contractors for selected project.
() =>
{
contractors.AddRange(contractorRepository.GetContractorsByProjectId(diary.ProjectId));
equipmentCategories.AddRange(contractorRepository.GetEquipmentCategories());
equipmentFuelTypes.AddRange(contractorRepository.GetEquipmentFuelTypes());
equipmentList.AddRange(contractorRepository.GetEquipmentByProjectId(this.Project.ProjectId));
// Reconstruct the contractor->Equipment->FuelType & Category relationship.
contractorViewModels.AddRange(
contractors.Select(contractor =>
new ContractorViewModel(
contractor,
equipmentList.Where(equipment =>
equipment.ContractorId == contractor.ContractorId).Select(e =>
new EquipmentViewModel(
e,
contractor,
equipmentCategories.FirstOrDefault(cat =>
cat.EquipmentCategoryId == e.EquipmentCategoryId),
equipmentFuelTypes.FirstOrDefault(f =>
f.EquipmentFuelTypeId == e.EquipmentFuelTypeId))))));
},
() =>
{
// Fetch all of the Sections, Bid-Items and Sub-items for the project
projectSections.AddRange(repository.GetSectionsByProjectId(project.ProjectId));
bidItemCollection.AddRange(repository.GetBidItemsByProjectId(project.ProjectId));
subItemCollection.AddRange(repository.GetSubItemsByProjectId(project.ProjectId));
// Reconstruct the Section->BidItem->SubItem hierarchy.
sectionViewModels.AddRange(
projectSections.Select(s =>
new SectionViewModel(project, s,
bidItemCollection.Where(b => b.SectionId == s.SectionId).Select(b =>
new BidItemViewModel(project, b,
subItemCollection.Where(si => si.BidItemId == b.BidItemId))))));
}
);
// Once the parallel invocations are completed, instance all of the children view models
// using the view model collections we just set up.
Parallel.Invoke(
// Fetch contractors for selected project.
() =>
this.DiaryDetailsViewModel = new DiaryDetailsViewModel(
project,
diary,
user),
() => // This view model works just fine, with same constructor signature.
this.DiaryDescriptionViewModel = new DiaryDescriptionViewModel(
project,
diary,
user,
sectionViewModels),
() =>
this.DiaryPayItemEditorViewModel = new DiaryPayItemEditorViewModel(
project,
diary,
user,
sectionViewModels),
() => // This view model does not notify the UI of changes to its collection.
this.DiaryEquipmentEditorViewModel = new DiaryEquipmentEditorViewModel(
project,
diary,
user,
contractorViewModels),
() =>
// For the Labor view, we just pass the Contractor model collection rather than the view model collection
// since the Labor view does not need any of the additional equipment information.
this.DiaryLaborViewModel = new DiaryLaborViewModel(
project,
diary,
user,
contractors));
});
}
public Project Project
{
get
{
return this.project;
}
set
{
this.project = value;
this.OnPropertyChanged();
}
}
public DiaryViewModel Diary
{
get
{
return this.diary;
}
set
{
this.diary = value;
this.OnPropertyChanged();
}
}
public DiaryDetailsViewModel DiaryDetailsViewModel
{
get
{
return this.diaryDetailsViewModel;
}
set
{
this.diaryDetailsViewModel = value;
this.OnPropertyChanged();
}
}
public DiaryDescriptionViewModel DiaryDescriptionViewModel
{
get
{
return this.diaryDescriptionViewModel;
}
set
{
this.diaryDescriptionViewModel = value;
this.OnPropertyChanged();
}
}
public DiaryPayItemEditorViewModel DiaryPayItemEditorViewModel
{
get
{
return this.diaryPayItemsViewModel;
}
set
{
this.diaryPayItemsViewModel = value;
this.OnPropertyChanged();
}
}
public DiaryLaborViewModel DiaryLaborViewModel
{
get
{
return this.diaryLaborViewModel;
}
set
{
this.diaryLaborViewModel = value;
this.OnPropertyChanged();
}
}
public DiaryEquipmentEditorViewModel DiaryEquipmentEditorViewModel
{
get
{
return this.diaryEquipmentEditorViewModel;
}
set
{
this.diaryEquipmentEditorViewModel = value;
this.OnPropertyChanged();
}
}
}
DiaryDescriptionViewModel
This view model works just fine, with its this.DiaryDescriptions collection being bound to properly and displayed in the ListView
public class DiaryDescriptionViewModel : BaseDiaryViewModel, IDataErrorInfo
{
private ObservableCollection<DiaryDescriptionDetailsViewModel> diaryDescriptions;
private DiaryDescriptionDetailsViewModel selectedDiaryDescription;
public DiaryDescriptionViewModel()
{
}
public DiaryDescriptionViewModel(Project project, Diary diary, UserViewModel user, List<SectionViewModel> sections)
: base(project, diary, user)
{
// Restore any previously saved descriptions.
var diaryRepository = new DiaryRepository();
List<DiaryDescription> descriptions = diaryRepository.GetDiaryDescriptionsByDiaryId(diary.DiaryId);
this.ProjectSections = sections;
// Reconstruct our descriptions
this.diaryDescriptions = new ObservableCollection<DiaryDescriptionDetailsViewModel>();
foreach (DiaryDescription description in descriptions)
{
SectionViewModel section = this.GetSectionContainingBidItemId(description.BidItemId);
BidItemViewModel bidItem = section.GetBidItem(description.BidItemId);
var details = new DiaryDescriptionDetailsViewModel(description, section, bidItem);
details.PropertyChanged += ChildViewModelPropertyChanged;
this.diaryDescriptions.Add(details);
}
this.diaryDescriptions.CollectionChanged += this.DiaryDescriptionsOnCollectionChanged;
this.IsDirty = false;
}
public ObservableCollection<DiaryDescriptionDetailsViewModel> DiaryDescriptions
{
get
{
return this.diaryDescriptions;
}
set
{
if (value != null)
{
this.diaryDescriptions.CollectionChanged -= this.DiaryDescriptionsOnCollectionChanged;
this.diaryDescriptions =
new ObservableCollection<DiaryDescriptionDetailsViewModel>(
value
.OrderBy(s => s.Section.Section)
.ThenBy(i => i.BidItem.BidItem.Number));
this.diaryDescriptions.CollectionChanged += this.DiaryDescriptionsOnCollectionChanged;
}
else
{
this.diaryDescriptions = new ObservableCollection<DiaryDescriptionDetailsViewModel>();
}
this.OnPropertyChanged();
}
}
public DiaryDescriptionDetailsViewModel SelectedDiaryDescription
{
get
{
return this.selectedDiaryDescription;
}
set
{
// Always unsubscribe from events before replacing the object. Otherwise we end up with a memory leak.
if (this.selectedDiaryDescription != null)
{
this.selectedDiaryDescription.PropertyChanged -= this.ChildViewModelPropertyChanged;
}
this.selectedDiaryDescription = value;
if (value != null)
{
// If the description contains a biditem DiaryId, then we go fetch the section and biditem
// associated with the diary description.
if (value.BidItemId > 0)
{
this.selectedDiaryDescription.Section = this.GetSectionContainingBidItemId(value.BidItemId);
this.selectedDiaryDescription.BidItem = this.selectedDiaryDescription.Section.GetBidItem(value.BidItemId);
}
// Subscribe to property changed events so we can set ourself to dirty.
this.selectedDiaryDescription.PropertyChanged += this.ChildViewModelPropertyChanged;
this.selectedDiaryDescription.IsDirty = false;
}
this.OnPropertyChanged();
this.IsDirty = false;
}
}
DiaryDescriptionDetailViewModel
Working child view model.
public class DiaryDescriptionDetailsViewModel : BaseChangeNotify
{
private readonly DiaryDescription diaryDescription;
private SectionViewModel section;
private BidItemViewModel bidItem;
public DiaryDescriptionDetailsViewModel(DiaryDescription description, SectionViewModel section = null, BidItemViewModel bidItem = null)
{
this.diaryDescription = description;
if (description.BidItemId > 0)
{
this.section = section;
this.bidItem = bidItem;
}
this.IsDirty = false;
}
public DiaryDescription Description
{
get
{
return this.diaryDescription;
}
}
public int BidItemId
{
get
{
return this.diaryDescription.BidItemId;
}
}
public BidItemViewModel BidItem
{
get
{
return this.bidItem;
}
set
{
this.bidItem = value;
this.diaryDescription.BidItemId = value.BidItem.BidItemId;
this.OnPropertyChanged();
}
}
public SectionViewModel Section
{
get
{
return this.section;
}
set
{
this.section = value;
this.OnPropertyChanged();
}
}
}
DiaryPayItemEditorViewModel
And finally, the view model who is not having its collection rendered to the view.
public class DiaryPayItemEditorViewModel : BaseDiaryViewModel, IDataErrorInfo
{
private ObservableCollection<DiaryPayItemDetailViewModel> diaryPayItemDetails;
private DiaryPayItemDetailViewModel selectedDiaryPayItemDetail;
private List<DiaryPayItem> allPayItemsForSelectedBidItem;
private decimal sumOfAllPayItemsForBidItem;
public DiaryPayItemEditorViewModel()
{
}
public DiaryPayItemEditorViewModel(Project project, Diary diary, UserViewModel user, List<SectionViewModel> sections)
: base(project, diary, user)
{
this.Initialize(project, sections);
this.IsDirty = false;
}
public ObservableCollection<DiaryPayItemDetailViewModel> DiaryPayItemDetails
{
get
{
return this.diaryPayItemDetails;
}
set
{
this.diaryPayItemDetails = value;
this.OnPropertyChanged();
}
}
public DiaryPayItemDetailViewModel SelectedDiaryPayItemDetail
{
get
{
return this.selectedDiaryPayItemDetail;
}
set
{
if (this.selectedDiaryPayItemDetail != null)
{
this.selectedDiaryPayItemDetail.PropertyChanged -= this.ChildViewModelPropertyChanged;
}
if (value != null)
{
value.PropertyChanged += this.ChildViewModelPropertyChanged;
}
this.selectedDiaryPayItemDetail = value;
this.OnPropertyChanged();
}
}
private void Initialize(Project project, List<SectionViewModel> sections)
{
var repository = new DiaryRepository();
var projectRepository = new ProjectRepository();
this.DiaryPayItemDetails = new ObservableCollection<DiaryPayItemDetailViewModel>();
this.ProjectSections = sections;
// Repository calls to the database.
List<DiaryPayItem> payItems = repository.GetDiaryPayItemsByDiaryId(this.Diary.DiaryId);
var sectionItems = projectRepository.GetSectionHierarchy(project.ProjectId);
// Temporary, needs to be refined.
foreach (var diaryPayItem in payItems)
{
var subItem = sectionItems.SubItems.FirstOrDefault(sub => sub.SubItemId == diaryPayItem.SubItemId);
var bidItems =
sectionItems.BidItems.Where(bid => bid.BidItemId == subItem.BidItemId)
.Select(
bid =>
new BidItemViewModel(project, bid,
sectionItems.SubItems.Where(sub => sub.BidItemId == bid.BidItemId)));
var section = new SectionViewModel(
project,
sectionItems.Sections.FirstOrDefault(s => bidItems.Any(bid => bid.BidItem.SectionId == s.SectionId)),
bidItems);
this.DiaryPayItemDetails.Add(
new DiaryPayItemDetailViewModel(
diaryPayItem,
section,
bidItems.FirstOrDefault(bid => bid.BidItem.BidItemId == subItem.BidItemId),
subItem));
}
}
DiaryPayItemDetailViewModel - Child view model to the troublesome view model
public class DiaryPayItemDetailViewModel : BaseChangeNotify
{
private DiaryPayItem diaryPayItem;
private SectionViewModel selectedSection;
private BidItemViewModel selectedBidItem;
private SubItem selectedSubItem;
public DiaryPayItemDetailViewModel(
DiaryPayItem diaryPayItem,
SectionViewModel section,
BidItemViewModel bidItem,
SubItem subItem)
{
this.DiaryPayItem = diaryPayItem;
this.SelectedSection = section;
this.SelectedBidItem = bidItem;
this.SelectedSubItem = subItem;
}
public DiaryPayItem DiaryPayItem
{
get
{
return this.diaryPayItem;
}
set
{
this.diaryPayItem = value;
this.OnPropertyChanged();
}
}
public SectionViewModel SelectedSection
{
get
{
return this.selectedSection;
}
set
{
this.selectedSection = value;
this.OnPropertyChanged();
}
}
public BidItemViewModel SelectedBidItem
{
get
{
return this.selectedBidItem;
}
set
{
this.selectedBidItem = value;
this.OnPropertyChanged();
}
}
public SubItem SelectedSubItem
{
get
{
return this.selectedSubItem;
}
set
{
this.selectedSubItem = value;
this.DiaryPayItem.SubItemId = value.SubItemId;
this.OnPropertyChanged();
}
}
XAML for the DiaryDescription Tab Item.
<ListView ItemsSource="{Binding Path=DiaryDescriptions}"
SelectedItem="{Binding Path=SelectedDiaryDescription}">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=Section.SectionName}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
XAML for Diary Pay Items tab item.
<ListView Name="PayItemListView"
ItemsSource="{Binding Path=DiaryPayItemDetails}">
<ListView.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=SelectedBidItem.BidItem.Description}" />
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
BaseChangeNotify
Lastly, to show my INotifyPropertyChanged implementation, I present my base class. It wraps all calls to the event handlers in an Application.Current.Dispatcher.Invoke() action. This forces all event handler calls to be ran on the main thread so I don't have to worry about cross-thread issues in my inherited objects.
public class BaseChangeNotify : INotifyPropertyChanged
{
private bool isDirty;
private UserViewModel user;
public BaseChangeNotify()
{
}
public BaseChangeNotify(UserViewModel user)
{
this.user = user;
}
public event PropertyChangedEventHandler PropertyChanged;
public bool IsDirty
{
get
{
return this.isDirty;
}
set
{
this.isDirty = value;
this.OnPropertyChanged();
}
}
public UserViewModel User
{
get
{
return this.user;
}
}
public virtual void OnPropertyChanged([CallerMemberName] string propertyName = "")
{
// Perform the IsDirty check so we don't get stuck in a infinite loop.
if (propertyName != "IsDirty")
{
this.IsDirty = true; // Each time a property value is changed, we set the dirty bool.
}
if (this.PropertyChanged != null)
{
// Invoke the event handlers attached by other objects.
try
{
// When unit testing, this will always be null.
if (Application.Current != null)
{
Application.Current.Dispatcher.Invoke(() =>
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName)));
}
else
{
this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
catch (Exception)
{
throw;
}
}
}
If anyone could help me figure this out I would greatly appreciate it. I have been trying various things for the last two days and can't get it figured out. It's weird how one view model works fine, essentially performing the same kind of operation, and the other does not.
Thanks in advance.

The DiaryEditorViewModel is the view model to a DiaryEditorWindow. The DiaryPayItemEditorViewModel belongs to a user control that resides within the Window. Setting the data context in the XAML at the Window level, for the TabItem, resolved this issue. Setting the DataContext at the UserControl level caused view model to not bind properly.
I also tried setting the datacontext in the constructor, but that had the same issue. It would never bind. By setting the datacontext in the XAML of the TabItem associated with the troublesome view model, the problem was resolved. I don't understand why this is an issue. Since the view model fully implements the property changed event, I should be able to set the data context at any point, and adjust the values without a problem.
Eitherway, I have been able to solve this issue.

Retaining enum values in asp.net

I have an asp.net page, wherein i am using enums (with Properties defined in class file in app_code)
Now my problem is whenever page gets postbacks the value of the enum in property gets resetted to the first one
I even tried setting the property as static, but still that didn't helped. below is my enum and property declaration:
private static UrlType _type;
public static UrlType UrlPattern
{
get
{
HttpContext.Current.Response.Write("GET: " +_type + "<br>");
return _type;
}
set
{
_type = value;
HttpContext.Current.Response.Write("SET : " +_type + "<br>");
}
}
public int VanityId { get; set; }
public enum UrlType
{
ArticleOnly,
ArticleCategoryCombination,
Normal,
TechForum
}
and this is how i calls:
public void BindRewrite()
{
GrdRewrite.DataSource = objVanity.GetAllRewriteVanities(Vanity.UrlPattern);
GrdRewrite.DataBind();
if (Vanity.UrlPattern == Vanity.UrlType.ArticleCategoryCombination)
{
GrdRewrite.Columns[2].Visible = false;
GrdRewrite.Columns[3].Visible = GrdRewrite.Columns[5].Visible = GrdRewrite.Columns[6].Visible = true;
}
else if (Vanity.UrlPattern == Vanity.UrlType.ArticleOnly)
{
GrdRewrite.Columns[5].Visible = true;
GrdRewrite.Columns[2].Visible = GrdRewrite.Columns[3].Visible = GrdRewrite.Columns[6].Visible = false;
}
else if (Vanity.UrlPattern == Vanity.UrlType.Normal)
{
GrdRewrite.Columns[2].Visible = true;
GrdRewrite.Columns[3].Visible = GrdRewrite.Columns[5].Visible = GrdRewrite.Columns[6].Visible = false;
}
}
protected void Page_Load(object sender, EventArgs e)
{
pnlAdmin.Visible = (objVanity.UserName == "host");
if (objVanity.UserName == "host")
Enable();
else
FieldsOpenForEditors(objVanity.SiteSupportUrlFormat);
if (!IsPostBack)
{
Vanity.GenerateListFromEnums(drpAdminUrlType);
if (objVanity.UserName == "host")
Vanity.UrlPattern = Vanity.UrlType.ArticleOnly;
else
Vanity.UrlPattern = objVanity.SiteSupportUrlFormat;
BindRewrite();
}
}
can anyone tell me how to retain the value of the enum across postbacks
i think viewstate could be option, but don't have any clue about how to store the enum value and restore the string value casted in enum.

If you want to persist a value between post back, you need to store it in Session, Cache or ViewState.
In your case, ViewState could be a prefer choice.
public UrlType UrlPattern
{
get
{
if (ViewState["UrlPattern"] != null)
return (UrlType)Enum.Parse(typeof(UrlType), ViewState["UrlPattern"].ToString());
return UrlType.Normal; // Default value
}
set
{
ViewState["UrlPattern"] = value;
}
}

Validator not passing ErrorMessage to ValidationSummary

I have written my own Validator and although the validator appears to be working (as it does display the Text property when invalid) the ValidationSummary does not display the ErrorMessage property, or anything, when validation fails. Interestingly, it appears that it fails to even display the Text property when I add another control with a validator to the page. What am I doing wrong?
public class RequiredCheckBoxListValidator : BaseValidator
{
private CheckBoxList _list;
private int _requiredCount = 1;
public int RequiredCount
{
get { return _requiredCount; }
set { _requiredCount = value; }
}
public RequiredCheckBoxListValidator()
{
EnableClientScript = false;
}
protected override bool ControlPropertiesValid()
{
Control control = FindControl(ControlToValidate);
if (control != null)
{
_list = (CheckBoxList)control;
return (_list != null);
}
else
{
return false;
}
}
protected override bool EvaluateIsValid()
{
return (_list.Items.Cast<ListItem>().Where(li => li.Selected).Count() == _requiredCount);
}
}

It would help to see your clientside info.
Without that, my guesses are to check ShowSummary on the validtorsummary to make sure it is not hiding the summary, and to see if the validators and summary are in separate UpdatePanels.