We Keep Coding

WPF DataGrid: how to know if ValidationTemplate is enabled

In a WPF application, I have a view with an editable datagrid and a viewmodel. This is an existing codebase, and a problem arises: there are fields in the viewmodel that raises exceptions but those fields are not in the view. A refactor is necessary, but for now we need to implement a visual clue (red border around the row) for the user as a quick fix.
From the viewmodel, I raise an event that a validation took place, and in the code-behind, I want to check in the datagridrow if the ValidationErrorTemplate is enabled.
As the elements added by the ValidationErrorTemplate are added as AdornerLayer outside of the datagridrows, it seems that I have no clue to which datagridrow this is coupled?
I have not much code to show, just that I get to the correct datagridrow for which viewmodel a validation took place:
private void OnValidationEvent(ValidationEventArgs e)
{
var rows = BoekingDatagrid.GetDataGridRow(e.ID);
if (e.HasErrors)
{
if (errorBorder == null)
{
row.BorderBrush = new SolidColorBrush(Colors.Red);
row.BorderThickness = new Thickness(1);
var vm = row.DataContext as ItemBaseViewModel;
LogValidationErrors(vm, UserContext);
}
}
else
{
row.BorderThickness = new Thickness(0);
}
}
Every column has the following xaml, with a Validation.ErrorTemplate:
<DataGridTemplateColumn Header="Name"
CanUserResize="False"
SortMemberPath ="Name"
Width="130"
MinWidth="130">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBox Text="{Binding Name, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
IsEnabled="{Binding ViewMode, Converter={StaticResource ViewModeToBoolean}, ConverterParameter=name}"
Validation.ErrorTemplate="{StaticResource ResourceKey=ErrorTemplate2_Grid}"/>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
ErrorTemplate2_Grid adds a red border and tooltip to the cell.
In Visual Live Tree, you can see that the rows and the error visuals, but they are not nested:
The question is: how can I find out if there are visual error elements added to the datagridrow, when the viewmodel is invalid?

Not sure what BindingGroup exactly does, but the databound rows does have there own BindingGroups with only the databindings of the controls in the row. And a very convenient property: HasValidationError
private void OnValidationEvent(ValidationEventArgs e)
{
var row = BoekingDatagrid.GetDataGridRow();
if (row != null)
{
if (e.HasErrors)
{
if (!row.BindingGroup.HasValidationError)
{
row.BorderBrush = new SolidColorBrush(Colors.Red);
row.BorderThickness = new Thickness(1);
}
else
{
row.BorderThickness = new Thickness(0);
}
}
else
{
row.BorderThickness = new Thickness(0);
}
}
}
Answered for mine and others future reference.

Validation in WPF is typically done using the interface INotifyDataErrorInfo. There are other ways too, but the ViewModel raising an event that the View handles isn't typically one of them. A very simplified model class could look like this:
public class Model : INotifyDataErrorInfo
{
public Model(int myInt, string myString)
{
MyInt = myInt;
MyString = myString;
}
public event EventHandler<DataErrorsChangedEventArgs> ErrorsChanged;
public bool HasErrors
{
get
{
try
{
return MyInt == 88 || MyString == "foo";
}
catch (Exception)
{
return true;
}
}
}
public int MyInt
{
get { throw new NotImplementedException(); }
set { }
}
public string MyString { get; set; }
public IEnumerable GetErrors(string propertyName)
{
try
{
if (propertyName == nameof(MyInt) && MyInt == 88)
return new string[] { "MyInt must not be 88" };
if (propertyName == nameof(MyString) && MyString == "foo")
return new string[] { "MyString must not be 'foo'" };
return new string[0];
}
catch (Exception)
{
return new string[] { "Exception" };
}
}
}
A quick and diry window could look like this:
public partial class MainWindow : Window
{
public MainWindow()
{
Models = new List<Model>
{
new Model(1,"hello"),
new Model(1,"foo"),
new Model(88,"hello"),
new Model(2,"world"),
};
DataContext = this;
InitializeComponent();
}
public List<Model> Models { get; set; }
}
whereas the XAML just contains <DataGrid ItemsSource="{Binding Models}" />
A red rectangle in case of an error is default. Just apply your custom template and do not set any ValidationErrorTemplate.

What could cause a binding to no update the source

I have a ComboBox defined like this:
<ComboBox
ItemsSource="{Binding Choices}"
SelectedItem="{Binding Value}"
Text="{Binding Text}"
IsEditable="True"
TextSearch.TextPath="Label"
DisplayMemberPath="Label" />
Here is my view Model:
public class ComboBoxViewModel : ViewModelBase
{
private string _selectedCode;
public ReadOnlyObservableCollection<ComboBoxItem> Choices { get; }
public ComboBoxItem Value
{
get { return this.Choices.FirstOrDefault(choice => choice.Code == _selectedCode); }
set
{
this.SetCode(value?.Code)
}
}
public string Text
{
get { return this.Value?.Label ?? _selectedCode; }
set
{
// Only set the code if no pre-defined code can be selected
if (this.Value == null)
{
this.SetCode(value)
}
}
}
public ComboBoxViewModel()
{
this.Choices = [..];
}
public bool SetCode(string code)
{
if (_selectedCode != code)
{
_selectedCode = code;
// Tried all the combination with/without/different order with no change
this.RaisePropertyChanged(nameof(this.Value));
this.RaisePropertyChanged(nameof(this.Text));
}
}
}
public class ComboBoxItem
{
public string Code { get; }
public string Label { get; }
public ComboBoxItem(string code, string label)
{
this.Code = code;
this.Label = label;
}
}
The Choices collection is initialized with some pair: Code,Label. I want to display the Label to the user and use the Code in my business layer. I also want my user to input its own code in the ComboBox (this is why the IsEditable dependency property is set to True and why I also bind Text on my ViewModel).
Everythings works fine when directly bind my ViewModel on the Control. The _selectedCode is updated prioritary with the selected Choices element or with the manual input if necessary.
My problem occurs when I pre-set the _selectedCode using the SetCode method. The Value property is no longer updated when I chose a new existing Choice in the ComboBox...
Is it possible to bind both SelectedItem and Text of a ComboBox? Do you have an idea why the bound properties are not updated after a programmatic initialization? It is like the event is not fired anymore...

Why is this ListView not changing with changes to the bound property?

Basic question from a novice. I've been stuck on this and have read through a lot of material and several similar questions on SO; hopefully not a completely duplicate question. I simplified the code as much as I know how to.
I'm trying to make the ListView show a filtered ObservableCollection) property (as the ItemsSource?), based on the selection in the ComboBox.
Specifically, which "meetings" have this "coordinator" related to it.
I'm not seeing any data errors in the output while it's running and debugging shows the properties updating correctly, but the ListView stays blank. I'm trying to avoid any code-behind on the View, there is none currently.
Thanks!
public class ViewModel : INotifyPropertyChanged
{
private ObservableCollection<Meeting> meetings;
public ObservableCollection<Meeting> Meetings
{
get
{
return meetings;
}
set
{
meetings = value;
OnPropertyChanged("ListProperty");
OnPropertyChanged("Meetings");
}
}
private string coordinatorSelected;
public string CoordinatorSelected
{
get
{
return coordinatorSelected;
}
set
{
coordinatorSelected = value;
Meetings = fakeDB.Where(v => v.CoordinatorName == CoordinatorSelected) as ObservableCollection<Meeting>;
}
}
private ObservableCollection<string> comboProperty = new ObservableCollection<string> { "Joe", "Helen", "Sven" };
public ObservableCollection<string> ComboProperty
{
get
{
return comboProperty;
}
}
private ObservableCollection<Meeting> fakeDB = new ObservableCollection<Meeting>() { new Meeting("Joe", "Atlas"), new Meeting("Sven", "Contoso"), new Meeting("Helen", "Acme") };
public ObservableCollection<Meeting> ListProperty
{
get
{
return Meetings;
}
}
public class Meeting
{
public string CoordinatorName { get; set; }
public string ClientName { get; set; }
public Meeting(string coordinatorName, string clientName)
{
CoordinatorName = coordinatorName;
ClientName = clientName;
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propertyName)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
XAML:
<Window.Resources>
<local:ViewModel x:Key="VM"></local:ViewModel>
</Window.Resources>
<DockPanel DataContext="{StaticResource ResourceKey=VM}">
<ComboBox Margin="10" ItemsSource="{Binding ComboProperty}" SelectedItem="{Binding CoordinatorSelected}" DockPanel.Dock="Top"/>
<ListView Margin="10" ItemsSource="{Binding ListProperty, UpdateSourceTrigger=PropertyChanged}" DisplayMemberPath="ClientName"/>
</DockPanel>
Update:
This seems to show that the lambda is returning a Meeting object but the assignment to Meetings is failing. Is this an error in casting maybe?
Thanks again.

You always have to change a property's backing field before you fire a PropertyChanged event. Otherwise a consumer of the event would still get the old value when it reads the property.
Change the Meetings property setter like this:
public ObservableCollection<Meeting> Meetings
{
get
{
return meetings;
}
set
{
meetings = value;
OnPropertyChanged("ListProperty");
OnPropertyChanged("Meetings");
}
}

I believe I've found two solutions to the same problem. The error pointed out #Clemens was also part of the solution. The Meetings property problem is solved if I change ListProperty and Meetings to IEnumerable. Alternatively this approach without changing the type, which I believe invokes the collection's constructor with the filtered sequence as an argument.
set
{
coordinatorSelected = value;
var filteredList = fakeDB.Where(v => v.CoordinatorName == coordinatorSelected);
Meetings = new ObservableCollection<Meeting>(filteredList);
OnPropertyChanged("ListProperty");
}

WPF Combobox binding and SelectedValue with SelectedValuePath

I am really struggling with data binding and the MVVM Methodology, though I like the concept I am just struggling. I have created a WPF for that has multiple comboboxes and a button. The first combobox will list database instance names. the remaining comboboxes will be populated after the button is clicked. Since I am having issues with the first, database instances, combobox I will only show my code for that. When the application starts up the combobox is loaded and the first item is selected, as expected. The issue is when I select a new name my method that I expect to get called does not. Can someone help me to understand why my method public DBInstance SelectedDBInstance is not getting executed when I have this in my XAML, SelectedValue="{Binding SelectedDBInstance, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}?
Here is my XAML for the database instances combobox. One question I have here is the "value" fpr SelectedValuePath, if I change it to say "DBInstanceName" it does not work.
<ComboBox x:Name="cbxRLFDBInstances" ItemsSource="{Binding DBInstances}"
SelectedValue="{Binding SelectedDBInstance, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
SelectedValuePath="value" DisplayMemberPath="DBInstanceName"/>
Here is my ViewModel Code:
namespace DatabaseTest.ViewModel
{
class RLFDatabaseTableViewModel : INotifyPropertyChanged
{
Utilities dbtUtilities = new Utilities();
public RelayCommand LoadDBInfoCommand
{
get;
set;
}
public RLFDatabaseTableViewModel()
{
LoadDBInstances();
LoadDBInfoCommand = new RelayCommand(LoadDBInfo);
}
public ObservableCollection<DBInstance> DBInstances
{
get;
set;
}
public void LoadDBInstances()
{
ObservableCollection<DBInstance> dbInstances = new ObservableCollection<DBInstance>();
DataTable dt = SmoApplication.EnumAvailableSqlServers(false);
dbInstances.Add(new DBInstance { DBInstanceName = "fal-conversion\\mun2012ci" });
dbInstances.Add(new DBInstance { DBInstanceName = "fal-conversion\\mun2014ci" });
if (dt.Rows.Count > 0)
{
foreach (DataRow dr in dt.Rows)
{
dbInstances.Add(new DBInstance { DBInstanceName = dr["Name"].ToString() });
}
}
DBInstances = dbInstances;
}
private DBInstance _selectedDBInstance;
public DBInstance SelectedDBInstance
{
get
{
return _selectedDBInstance;
}
set
{
_selectedDBInstance = value;
RaisePropertyChanged("SelectedDBInstance");
//ClearComboBoxes();
}
}
}
}
Here is my Model code. When I step through the code this method, public string DBInstanceName, gets executed multiple time. I do not know why and it is seems wasteful to me.
namespace DatabaseTest.Model
{
public class RLFDatabaseTableModel { }
public class DBInstance : INotifyPropertyChanged
{
private string strDBInstance;
public override string ToString()
{
return strDBInstance;
}
public string DBInstanceName
{
get
{
return strDBInstance;
}
set
{
if (strDBInstance != value)
{
strDBInstance = value;
RaisePropertyChanged("DBInstanceName");
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string property)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(property));
}
}
}

You should bind the SelectedItem property of the ComboBox to the SelectedDBInstance property and get rid of the SelectedValuePath:
<ComboBox x:Name="cbxRLFDBInstances" ItemsSource="{Binding DBInstances}"
SelectedItem="{Binding SelectedDBInstance, UpdateSourceTrigger=PropertyChanged}"
DisplayMemberPath="DBInstanceName"/>
The SelectedValuePath property is only used when you want to bind to a source property that is not of the same type as the item in the ItemsSource collection.
To select an item initially you should set the SelectedDBInstance property to an item that is present in the DBInstances collection:
public RLFDatabaseTableViewModel()
{
LoadDBInstances();
LoadDBInfoCommand = new RelayCommand(LoadDBInfo);
SelectedDBInstance = DBInstances[0]; //selected the first item
}

Prevent ComboBox from setting the selectedValue to null when it's not in the bound list

I'm not quite sure how to deal with this problem. I'm using a bunch of comboboxes with dropdown lists of values we allow the user to set a property too. (i.e. Currencies = "USD, CAD, EUR").
Every now and then, when we load data, we'll find the currency is something not in our list, like "AUD". In this case, we still want the combobox to display the loaded value, and the current selected Currency should remain "AUD" unless the user chooses to change it, in which case their only options will still be "USD, CAD, EUR".
My problem is that as soon as the control becomes visible, the ComboBox is calling the setter on my SelectedCurrency property and setting it to null, presumably because the current value "AUD" isn't in it's list. How can I disable this behaviour without making it possible for the user to type whatever they want into the Currency field?

Set IsEditable="True", IsReadOnly="True", and your SelectedItem equal to whatever object you want to hold the selected item
<ComboBox ItemsSource="{Binding SomeCollection}"
Text="{Binding CurrentValue}"
SelectedItem="{Binding SelectedItem}"
IsEditable="True"
IsReadOnly="True">
IsEditable allows the Text property to show a value not in the list
IsReadOnly makes it so the Text property is not editable
And SelectedItem stores the selected item. It will be null until the user selects an item in the list, so in your SaveCommand, if SelectedItem == null then use CurrentValue instead of SelectedItem when saving to the database

This seems to be a reasonably common problem. Imagine you have a lookup list in the database, maybe a list of employees. The employee table has a 'works here' flag. Another table references the employee lookup list. When a person leaves the company, you want your views to show the name of the old employee, but not allow the old employee to be assigned in future.
Here's my solution to the similar currency problem:
Xaml
<Page.DataContext>
<Samples:ComboBoxWithObsoleteItemsViewModel/>
</Page.DataContext>
<Grid>
<ComboBox Height="23" ItemsSource="{Binding Items}"
SelectedItem="{Binding SelectedItem}"/>
</Grid>
C#
// ViewModelBase and Set() are from MVVM Light Toolkit
public class ComboBoxWithObsoleteItemsViewModel : ViewModelBase
{
private readonly string _originalCurrency;
private ObservableCollection<string> _items;
private readonly bool _removeOriginalWhenNotSelected;
private string _selectedItem;
public ComboBoxWithObsoleteItemsViewModel()
{
// This value might be passed in to the VM as a parameter
// or obtained from a data service
_originalCurrency = "AUD";
// This list is hard-coded or obtained from your data service
var collection = new ObservableCollection<string> {"USD", "CAD", "EUR"};
// If the value to display isn't in the list, then add it
if (!collection.Contains(_originalCurrency))
{
// Record the fact that we may need to remove this
// value from the list later.
_removeOriginalWhenNotSelected = true;
collection.Add(_originalCurrency);
}
Items = collection;
SelectedItem = _originalCurrency;
}
public string SelectedItem
{
get { return _selectedItem; }
set
{
// Remove the original value from the list if necessary
if(_removeOriginalWhenNotSelected && value != _originalCurrency)
{
Items.Remove(_originalCurrency);
}
Set(()=>SelectedItem, ref _selectedItem, value);
}
}
public ObservableCollection<string> Items
{
get { return _items; }
private set { Set(()=>Items, ref _items, value); }
}
}

You should set IsEditable of the ComboBox to true and bind the Text property instead of the SelectedValue property.

If IsEditable = false then ComboBox does not support a value not in the list.
If you want user action to add a value but not edit that value or any existing values then one approach might be to put the new value in TextBlock (not editable) and a Button to let them add that value. If they select any value from the combobox then hide the TextBlock and Button.
Another approach would be to add the value to the list with more complex logic behind that if any another value is selected then that tentative value is removed. And the tentative value does not get persisted until it is selected.

He doesn't want to be users to be able to type, so IsEditable seems to be off the table.
What I would do is just add the new value AUD to the Item list as
ComboBoxItem Content="AUD" Visibility="Collapsed"
Then Text="AUD" will work in code but not from the drop down.
To be fancy, one could make a converter for the ItemsSource that binds to the TEXT box and adds it collapsed automatically

Here was my solution to this problem:
XAML looks like this:
<DataTemplate>
<local:CCYDictionary Key="{TemplateBinding Content}">
<local:CCYDictionary.ContentTemplate>
<DataTemplate>
<ComboBox Style="{StaticResource ComboBoxCellStyle}"
SelectedValuePath="CCYName"
DisplayMemberPath="CCYName"
TextSearch.TextPath="CCYName"
ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type local:CCYDictionary}}, Path=ListItems}"
SelectedValue="{Binding}" />
</DataTemplate>
</local:CCYDictionary.ContentTemplate>
</local:CCYDictionary>
</DataTemplate>
<!-- For Completion's sake, here's the style and the datacolumn using it -->
<Style x:Key="ComboBoxCellStyle" TargetType="ComboBox">
<Setter Property="IsEditable" Value="False"/>
<Setter Property="IsTextSearchEnabled" Value="True"/>
<!-- ...other unrelated stuff (this combobox was was a cell template for a datagrid) -->
</Style>
<Column FieldName="CCYcode" Title="Currency" DataTemplate="{StaticResource CCYEditor}" />
There's probably a nicer way for the dictionary to expose the ItemsSource so that the Bindings aren't so ugly, but once I got it to work I was too tired of the problem to refine it further.
Individual dictionaries declared like so:
public class CCYDictionary : DataTableDictionary<CCYDictionary>
{
protected override DataTable table { get { return ((App)App.Current).ApplicationData.CCY; } }
protected override string indexKeyField { get { return "CCY"; } }
public CCYDictionary() { }
}
public class BCPerilDictionary : DataTableDictionary<BCPerilDictionary>
{
protected override DataTable table { get { return ((App)App.Current).ApplicationData.PerilCrossReference; } }
protected override string indexKeyField { get { return "BCEventGroupID"; } }
public BCPerilDictionary() { }
}
//etc...
Base class looks like:
public abstract class DataTableDictionary<T> : ContentPresenter where T : DataTableDictionary<T>
{
#region Dependency Properties
public static readonly DependencyProperty KeyProperty = DependencyProperty.Register("Key", typeof(object), typeof(DataTableDictionary<T>), new PropertyMetadata(null, new PropertyChangedCallback(OnKeyChanged)));
public static readonly DependencyProperty RowProperty = DependencyProperty.Register("Row", typeof(DataRowView), typeof(DataTableDictionary<T>), new PropertyMetadata(null, new PropertyChangedCallback(OnRowChanged)));
public static readonly DependencyProperty ListItemsProperty = DependencyProperty.Register("ListItems", typeof(DataView), typeof(DataTableDictionary<T>), new PropertyMetadata(null));
public static readonly DependencyProperty IndexedViewProperty = DependencyProperty.Register("IndexedView", typeof(DataView), typeof(DataTableDictionary<T>), new PropertyMetadata(null));
#endregion Dependency Properties
#region Private Members
private static DataTable _SourceList = null;
private static DataView _ListItems = null;
private static DataView _IndexedView = null;
private static readonly Binding BindingToRow;
private static bool cachedViews = false;
private bool m_isBeingChanged;
#endregion Private Members
#region Virtual Properties
protected abstract DataTable table { get; }
protected abstract string indexKeyField { get; }
#endregion Virtual Properties
#region Public Properties
public DataView ListItems
{
get { return this.GetValue(ListItemsProperty) as DataView; }
set { this.SetValue(ListItemsProperty, value); }
}
public DataView IndexedView
{
get { return this.GetValue(IndexedViewProperty) as DataView; }
set { this.SetValue(IndexedViewProperty, value); }
}
public DataRowView Row
{
get { return this.GetValue(RowProperty) as DataRowView; }
set { this.SetValue(RowProperty, value); }
}
public object Key
{
get { return this.GetValue(KeyProperty); }
set { this.SetValue(KeyProperty, value); }
}
#endregion Public Properties
#region Constructors
static DataTableDictionary()
{
DataTableDictionary<T>.BindingToRow = new Binding();
DataTableDictionary<T>.BindingToRow.Mode = BindingMode.OneWay;
DataTableDictionary<T>.BindingToRow.Path = new PropertyPath(DataTableDictionary<T>.RowProperty);
DataTableDictionary<T>.BindingToRow.RelativeSource = new RelativeSource(RelativeSourceMode.Self);
}
public DataTableDictionary()
{
ConstructDictionary();
this.SetBinding(DataTableDictionary<T>.ContentProperty, DataTableDictionary<T>.BindingToRow);
}
#endregion Constructors
#region Private Methods
private bool ConstructDictionary()
{
if( cachedViews == false )
{
_SourceList = table;
if( _SourceList == null )
{ //The application isn't loaded yet, we'll have to defer constructing this dictionary until it's used.
return false;
}
_SourceList = _SourceList.Copy(); //Copy the table so if the base table is modified externally we aren't affected.
_ListItems = _SourceList.DefaultView;
_IndexedView = CreateIndexedView(_SourceList, indexKeyField);
cachedViews = true;
}
ListItems = _ListItems;
IndexedView = _IndexedView;
return true;
}
private DataView CreateIndexedView(DataTable table, string indexKey)
{
// Create a data view sorted by ID ( keyField ) to quickly find a row.
DataView dataView = new DataView(table);
dataView.Sort = indexKey;
dataView.ApplyDefaultSort = true;
return dataView;
}
#endregion Private Methods
#region Static Event Handlers
private static void OnKeyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
// When the Key changes, try to find the data row that has the new key.
// If it is not found, return null.
DataTableDictionary<T> dataTableDictionary = sender as DataTableDictionary<T>;
if( dataTableDictionary.m_isBeingChanged ) return; //Avoid Reentry
dataTableDictionary.m_isBeingChanged = true;
try
{
if( dataTableDictionary.IndexedView == null ) //We had to defer loading.
if( !dataTableDictionary.ConstructDictionary() )
return; //throw new Exception("Dataview is null. Check to make sure that all Reference tables are loaded.");
DataRowView[] result = _IndexedView.FindRows(dataTableDictionary.Key);
DataRowView dataRow = result.Length > 0 ? result[0] : null;
//Sometimes a null key is valid - but sometimes it's just xceed being dumb - so we only skip the following step if it wasn't xceed.
if( dataRow == null && dataTableDictionary.Key != null )
{
//The entry was not in the DataView, so we will add it to the underlying table so that it is not nullified. Treaty validation will take care of notifying the user.
DataRow newRow = _SourceList.NewRow();
//DataRowView newRow = _IndexedView.AddNew();
int keyIndex = _SourceList.Columns.IndexOf(dataTableDictionary.indexKeyField);
for( int i = 0; i < _SourceList.Columns.Count; i++ )
{
if( i == keyIndex )
{
newRow[i] = dataTableDictionary.Key;
}
else if( _SourceList.Columns[i].DataType == typeof(String) )
{
newRow[i] = "(Unrecognized Code: '" + (dataTableDictionary.Key == null ? "NULL" : dataTableDictionary.Key) + "')";
}
}
newRow.EndEdit();
_SourceList.Rows.InsertAt(newRow, 0);
dataRow = _IndexedView.FindRows(dataTableDictionary.Key)[0];
}
dataTableDictionary.Row = dataRow;
}
catch (Exception ex)
{
throw new Exception("Unknow error in DataTableDictionary.OnKeyChanged.", ex);
}
finally
{
dataTableDictionary.m_isBeingChanged = false;
}
}
private static void OnRowChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
// When the Key changes, try to find the data row that has the new key.
// If it is not found, return null.
DataTableDictionary<T> dataTableDictionary = sender as DataTableDictionary<T>;
if( dataTableDictionary.m_isBeingChanged ) return; //Avoid Reentry
dataTableDictionary.m_isBeingChanged = true;
try
{
if( dataTableDictionary.Row == null )
{
dataTableDictionary.Key = null;
}
else
{
dataTableDictionary.Key = dataTableDictionary.Row[dataTableDictionary.indexKeyField];
}
}
catch (Exception ex)
{
throw new Exception("Unknow error in DataTableDictionary.OnRowChanged.", ex);
}
finally
{
dataTableDictionary.m_isBeingChanged = false;
}
}
#endregion Static Event Handlers
}