WPF Datagrid展平集合对象的集合

Question

I need your help. I have a collection of objects which has collections inside and I need to display the values inside of them.

This is my collection Element. A List of them will later be bound to the Datagrid (ObjectBase is only an implementation of INotifyPropertyChanged)

public class ElementContainer : ObjectBase
{
    public Element ContainerElement { get; set; }

    private ObservableCollection<State> _elementStates;

    public ObservableCollection<State> ElementStates
    {
        get { return _elementStates; }
        set { _elementStates = value; OnPropertyChanged(); }
    }
}

My elements:

public class Element
{
    public int Nbr { get; set; }
    public string Name { get; set; }
}

public class State: ObjectBase
{
    public string Name { get; set; }

    private bool _value;

    public bool Value
    {
        get { return _value; }
        set { _value = value; OnPropertyChanged(); }
    }

    public string StateType { get; set; }
}

The "Value" property of the State object is what I need get updated if it changed.

My ViewModel:

public class MainViewModel : ObjectBase
{

    private IList<ElementContainer> _enitites;

    public IList<ElementContainer> Enitites
    {
        get { return _enitites; }
        set { _enitites = value; OnPropertyChanged(); }
    }

    public MainViewModel()
    {
        Enitites = new ObservableCollection<ElementContainer>()
        {
            new ElementContainer() {
                                       ContainerElement =  new Element() {Nbr= 1, Name= "Test 1" },
                                       ElementStates = new ObservableCollection<State>()
                                       {
                                            new State() { Name = "On", Value = true,  StateType= "On" },
                                            new State() { Name = "Open", Value = false,  StateType= "Open" }
                                       }
                                    },

             new ElementContainer() {
                                       ContainerElement =  new Element() {Nbr= 2, Name= "Test 2" },
                                       ElementStates = new ObservableCollection<State>()
                                       {
                                            new State() { Name = "On", Value = false, StateType= "On" },
                                            new State() { Name = "Open", Value = true, StateType= "Open" }
                                       }
                                    }

         };
    }
}

Now the Datagrid should have following columns:

Nbr, Name, On, Open

The CellValue of the "On" and "Open" columns should be the value property of the State.

Any ideas?

Edit:

What I also tried is to create an AttachedProperty for creating the columns:

public class ElementStatesGridExtensions
{
    public static ObservableCollection<ColumnConfig> GetColumnConfigs(DependencyObject obj)
    {
        return (ObservableCollection<ColumnConfig>)obj.GetValue(ColumnConfigsProperty);
    }

    public static void SetColumnConfigs(DependencyObject obj, ObservableCollection<ColumnConfig> value)
    {
        obj.SetValue(ColumnConfigsProperty, value);
    }


    public static readonly DependencyProperty ColumnConfigsProperty =
        DependencyProperty.RegisterAttached("ColumnConfigs", typeof(ObservableCollection<ColumnConfig>), typeof(ElementStatesGridExtensions), new PropertyMetadata(new PropertyChangedCallback(OnColumnsChanged)));

    static DeviceStateConverter converter = new DeviceStateConverter();

    static FrameworkElementFactory CreateFrameWorkFactoryWithBinding(ColumnConfig config)
    {
        var fwf = new FrameworkElementFactory(typeof(TextBlock));

        if (config != null && config.ColumnType != null)
        {

            if (config.ColumnType.Equals("State"))
            {
                fwf.SetBinding(TextBlock.TextProperty, new Binding("ElementStates")
                {
                    ConverterParameter = config.ColumnName,
                    Converter = converter,

                    UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged,
                    Mode = BindingMode.OneWay
                });
            }
        }
        return fwf;
    }


    static void OnColumnsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var dataGrid = d as DataGrid;
        dataGrid.Columns.Clear();


        dataGrid.Columns.Add(new DataGridTextColumn() { Header = "Nbr", Binding = new Binding("ContainerElement.Nbr") });
        dataGrid.Columns.Add(new DataGridTextColumn() { Header = "Name", Binding = new Binding("ContainerElement.Name") });


        foreach (var columnConfig in GetColumnConfigs(d))
        {
            dataGrid.Columns.Add(new DataGridTemplateColumn()
            {
                Header = columnConfig.ColumnHeader,
                CellTemplate = new DataTemplate()
                {
                    VisualTree = CreateFrameWorkFactoryWithBinding(columnConfig)
                }
            });
        }
    }
}

public class DeviceStateConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is ObservableCollection<stof.State> deviceStates && parameter != null)
        {
            var deviceState = deviceStates.FirstOrDefault(s => s.StateType?.ToUpper() == parameter.ToString().ToUpper());

            if (deviceState != null)
                return deviceState.Value;

        }

        return false;
    }
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

Then I attached this property to the datagrid. And added this ...

public void RefeshStates(object sender, EventArgs e)
    {
        OnPropertyChanged("ElementStates");
    }

to the ElementContainer class.

Then in the ViewModel I iterate through all entities and register the PropertyChanged event of every state to the ElementContainer. So now if the state value changes, the Container gets notified and the Collection will refresh. That's not a good solution. Also the states of all other elements will be updated.

 foreach (ElementContainer container in Enitites)
        {

            foreach (State s in container.ElementStates)
            {
                s.PropertyChanged += container.RefeshStates;
            }
        }

Answer 1

Is ElementStates length always 2? if yes than tere are two options:

1. Option 1: You can include both State values into your ElementContainer class as Properties.
2. Option 2: You can call something like this var q = Enitites.Select(e=>e.Nbr, e.Name, e.ElementStates.Where(es=>es.Name="On").First().Value, e.ElementStates.Where(es=>es.Name="Open").First().Value);