Update itemssource in PersistChanges when working with a primitive collection editor

[ykarpeev]

If I have a viewmodel that I bind to the propertygrid that has a property such as:

   public List<string> ListOfStrings
   {
       get => this.AppSettings.Strings;

       set => this.AppSettings.Strings = value;
   }

When editing the collection I do not see the "set" called when the changes are made. This change allows for it to happen.

[XceedBoucherS]

Hello,

I wrote a sample to test your situation. Please correct it if not accurate.

<StackPanel> <xctk:PropertyGrid SelectedObject="{Binding}" /> <Button Content="TEST" Click="Button_Click" /> </StackPanel>

`public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();

this.DataContext = new MyObject();
var testObjectCount = (this.DataContext as MyObject).ListOfStrings.Count;  // returns 0 item.

}

private void Button_Click( object sender, RoutedEventArgs e )
{
var testObject = this.DataContext as MyObject;
var testObjectCount = testObject.ListOfStrings.Count; // returns the X items added.
}
}

public class MyObject
{
List m_list = new List();

public string Name { get; set; }

public List ListOfStrings
{
get => m_list;

set => m_list = value;

}
}`

Steps:
-Run the app
-A breakpoint on line
var testObjectCount = (this.DataContext as MyObject).ListOfStrings.Count; // returns 0 item.
will return no items in the list.
-Use the PropertyGrid to add 3 items in the list.
-Click the Button
-A breakpoint on line:
var testObjectCount = testObject.ListOfStrings.Count; // returns the X items added.
will return a list with 3 items.

so the MyObjects is correctly updated.
Am I missing something ?
Thanks

[ykarpeev]

For me I was using MVVM and here is what I have:

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1" xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>

        <xctk:PropertyGrid SelectedObject="{Binding}"></xctk:PropertyGrid>
    </Grid>
</Window>

 public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            this.DataContext = new MainViewModel();
        }
    }

    public class MainViewModel
    {
        public List<string> test = new List<string>();

        public List<string> Test
        {
            get
            {
                return test;
            }

            set
            {
                test = value;
            }
        }
    }

When changing the collection in the propertygrid the Set method on Test is never called - but it does work with these changes.

[XceedBoucherS]

The setter of MainViewModel.Test won't be called because this collection is always the same. Only its content is modified through the PropertyGrid Collection Editor.

[ykarpeev]

Thanks. In this case for me the propertygrid is bound to a configuration class & when the Set is called on a property I save the settings to a file & so having an indification that the collection changed works really well. That's why I made this change - I couldn't find a way to get that notification any other way.