How to define a dependency property on a custom column and use the row item as datacontext

[Licenses]

Hello,

I have a grid bound to a collection of items.

An item has several properties and one property is a combination of 4 properties (omitted INotifyPropertyChanged etc):

public class MyItemViewModel
{
    public int Number { get; set; }
    public string NumberSeperator { get; set; }
    public int SubNumber { get; set; }
    public string SubSubNumber { get; set; }

    public string FullNumber {
        get
        {
            return string.Format("{0}{1}{2}{3}", Number, NumberSeperator, SubNumber, SubSubNumber);
        }
    }
}

There are of course more properties available but the focus is on these properties mentioned.
Now, I tried creating a custom column which will, in view mode, display the FullNumber property and in edit mode create 4 masked text boxes to edit those 4 properties seperatly (Number, NumberSeperator, SubNumber and SubSubNumber)

So I figured the cleanest & easiest way to do this was to define 5 dependency properties on the custom column, 1 for each property, so that I could bind to them in my xaml code:

<MyCustomColumn NumberBinding="{Binding Number}" NumberSeperatorBinding="{Binding NumberSeperator}" SubNumberBinding="{Binding SubNumber}" SubSubNumberBinding="{Binding SubSubNumber}" />

So my column looked a bit like this:

public class MyCustomColumn : GridViewBoundColumnBase
{
    public Binding NumberBinding
    {
        get { return (Binding)GetValue(NumberBindingProperty); }
        set { SetValue(NumberBindingProperty, value); }
    }
    public static readonly DependencyProperty NumberBindingProperty =
        DependencyProperty.Register("NumberBinding", typeof(Binding), typeof(MyCustomColumn), new PropertyMetadata(null));

    public Binding NumberSeperatorBinding
    {
        get { return (Binding)GetValue(NumberSeperatorBindingProperty); }
        set { SetValue(NumberSeperatorBindingProperty, value); }
    }
    public static readonly DependencyProperty NumberSeperatorBindingProperty =
        DependencyProperty.Register("NumberSeperatorBinding", typeof(Binding), typeof(MyCustomColumn), new PropertyMetadata(null));

    public Binding SubNumberBinding
    {
        get { return (Binding)GetValue(SubNumberBindingProperty); }
        set { SetValue(SubNumberBindingProperty, value); }
    }
    public static readonly DependencyProperty SubNumberBindingProperty =
        DependencyProperty.Register("SubNumberBinding", typeof(Binding), typeof(MyCustomColumn), new PropertyMetadata(null));

    public Binding SubSubNumberBinding
    {
        get { return (Binding)GetValue(SubSubNumberBindingProperty); }
        set { SetValue(SubSubNumberBindingProperty, value); }
    }
    public static readonly DependencyProperty SubSubNumberBindingProperty =
        DependencyProperty.Register("SubSubNumberBinding", typeof(Binding), typeof(MyCustomColumn), new PropertyMetadata(null));
}

So when overriding the CreateCellEditElement function, I implemented is as such:

public override FrameworkElement CreateCellEditElement(GridViewCell cell, object dataItem)
 {
    var e1 = new RadMaskedNumericInput();
    e1.SetBinding(RadMaskedNumericInput.ValueProperty, NumberBinding);

    var e2 = new RadMaskedTextInput();
    e2.SetBinding(RadMaskedTextInput.ValueProperty, NumberSeperatorBinding);

    var e3 = new RadMaskedNumericInput();
    e3.SetBinding(RadMaskedNumericInput.ValueProperty, SubNumberBinding);

    var e4 = new RadMaskedTextInput();
    e4.SetBinding(RadMaskedTextInput.ValueProperty, SubSubNumberBinding);

    var wp = new WrapPanel();

    wp.Children.Add(e1);
    wp.Children.Add(e2);
    wp.Children.Add(e3);
    wp.Children.Add(e4);

    return wp;
 }

However, when using this column it will complain that it can't find the Number, NumberSeperator, SubNumber and SubSubNumber properties on the viewmodel, which is the datacontext of the grid.

I thought it would work the same as the DataMemberBinding and automatically use as datacontext, the row item.

Any help would be appreciated :)

[Licenses]

Any ideas?

[Dimitrina]

Hello,

You just set the DataContext for RadGridView. 

In order to have the DataContext of each GridViewRow to be an object from the bound collection, you need to have set an ItemsSource collection for RadGridView.

To get the Binding still be resolved in your case, you could specify a valid Source for it. You can define the MyItemViewModel as a StaticResource and then set it as a Source.

Regards,
Didie
Telerik

[Pablo]

Sorry,

I have the same problem. Did you find a solution?

[Stefan]

Hi Pablo,

Can you please check out the Create Custom Column Editor and Create Custom Editor topics, as I believe you will find them helpful on this matter?

Hope this helps.

Best Regards,
Stefan X1
Telerik

[Sdfg]

Did anyone solve this? I have the same problem.

Regarding suggested solutions;

Dimitrina: The question about datacontext is for the context of the binding in the custom column, not for the gridview.

Stefan X1: Those topics doesn't cover this scenario creating a new bindable property for the column that should bind on the child elements like the datamemberbinding does.