Binding WPF GridViewColumn to method with parameter

Question

I am trying to bind GridViewColumn to a method with parameter.

My current XAML looks like this:

<ListView Margin="10" ItemsSource="{DynamicResource RemoteAgents}" Name="lvRemoteAgents" DataContext="">
        <ListView.View>
            <GridView>
                <GridViewColumn Header="ID" DisplayMemberBinding="{Binding Value.ID}" />
                <GridViewColumn Header="Name" DisplayMemberBinding="{Binding Value.name}" />
                <GridViewColumn Header="Type" DisplayMemberBinding="{Binding Value.type}" />
            </GridView>
        </ListView.View>
    </ListView>

ID, name and types are predefined properties of the ItemSource class. These properties are actually fields of the JSON structure. So instead of binding to the properties I want to access JSON field by the field name. In pseudo-code I would look like this:

   <ListView Margin="10" ItemsSource="{DynamicResource RemoteAgents}" Name="lvRemoteAgents" DataContext="">
        <ListView.View>
            <GridView>
                <GridViewColumn Header="ID" DisplayMemberBinding="{Binding Value.GetValue('ID')}" />
                <GridViewColumn Header="Name" DisplayMemberBinding="{Binding Value.GetValue('name')}" />
                <GridViewColumn Header="Type" DisplayMemberBinding="{Binding Value.GetValue('type')}" />
            </GridView>
        </ListView.View>
    </ListView>

I defined ObjectDataProvider as

<ObjectDataProvider x:Key="GetValue"
        ObjectType="{x:Type local:RemoteAgent}"
        MethodName="GetField">
        <ObjectDataProvider.MethodParameters>
            <system:String>empty</system:String>
        </ObjectDataProvider.MethodParameters>
    </ObjectDataProvider>

And now I bind to the OjbectDataProvider as follows:

<GridViewColumn Header="ID" DisplayMemberBinding="{Binding Source={StaticResource GetValue}, BindsDirectlyToSource=True, Mode=OneWayToSource}" />

My problem is how to pass parameter to GetValue function.

I won't need to define property for each field in JSON structure. And if JSON changes all I need is to change XAML without touching the code behind. — sergman, Jan 28 '16 at 22:07
How you can achieve this without changing at least method `GetField`? — Hamlet Hakobyan, Jan 28 '16 at 22:09
To access JSON field is like dictionary return json[fieldName]; — sergman, Jan 28 '16 at 22:11
I think it is something artificial but you can make your method `GetField` return `Dictionary` and create a converter which will return `Value` of `Key` passed as `ConverterParameter`. — Hamlet Hakobyan, Jan 28 '16 at 22:34
That makes sense. On the other hand it would be convenient to access methods with parameters — sergman, Jan 28 '16 at 22:45
Have you tried deserializing the JSON into a typed or anonymous .NET object and binding to it directly? — Johannes Wanzek, Jan 29 '16 at 07:00

score 0 · Answer 1 · answered Jan 29 '16 at 08:38

I think you can achieve your goal by writing class that inherits DynamicObject.The method you should override in your implementation is TryGetMember.

Look Here for example. Generally speaking, you are "mocking up" your function calls into the dynamic objects, and XAML in your case will look like:

<GridViewColumn Header="ID" DisplayMemberBinding="{Binding Value.ID}" />

Where Value is path to the instance of your dynamic object.

Another way is using IValueConverter, passing parameter through ConverterParameter.

Asssuming you have added a ValueConverter to your resources, code will look like this:

<GridViewColumn Header="ID" DisplayMemberBinding="{Binding Value,Converter={StaticRessource myConverter,ConverterParameter=ID}}" />

Keep in mind that ConverterParameter is not DependencyProperty, so you cannot bind to it.

Binding WPF GridViewColumn to method with parameter

1 Answers1