[Solved] Selected Item not displayed

[Chris]

When displaying "Name" from button collection, selected item is not displayed.
It looks pretty straight forward but I can't think of why it won't work.. hmm..
Is this a telerik bug?
The following code shows two different methods, "DataTemplate" and "DisplayMemberPath"
I appreciate for your help.
-chris

<Window x:Class="RadComboBoxExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        Title="MainWindow" Height="350" Width="525">
    <Grid x:Name="grid">
        <Grid.Resources>
            <DataTemplate x:Key="comboTemplate">
                <TextBlock Text="{Binding Name}" />
            </DataTemplate>
        </Grid.Resources>
        <Grid.ColumnDefinitions>
            <ColumnDefinition />
            <ColumnDefinition />
        </Grid.ColumnDefinitions>

        <StackPanel Grid.Column="0" Orientation="Vertical">
            <TextBlock Text="Use ItemTemplate" Margin="10" FontSize="15" HorizontalAlignment="Center" />
            <telerik:RadComboBox x:Name="comboBox1" Width="100" Height="30"
                                 ItemsSource="{Binding ButtonCollection1}"
                                 SelectedItem="{Binding SelectedButton1}"
                                 ItemTemplate="{StaticResource comboTemplate}"/>
        </StackPanel>

        <StackPanel Grid.Column="1" Orientation="Vertical">
            <TextBlock Text="Use DisplayMemberPath" Margin="10" FontSize="15" HorizontalAlignment="Center" />
            <telerik:RadComboBox x:Name="comboBox2" Width="100" Height="30"
                                 Grid.Column="1"
                                 ItemsSource="{Binding ButtonCollection2}"
                                 SelectedItem="{Binding SelectedButton2}"
                                 DisplayMemberPath="Name"/>
        </StackPanel>
    </Grid>
</Window>

using System.Collections.ObjectModel;
using System.Windows;
using Telerik.Windows.Controls;

namespace RadComboBoxExample
{
    public partial class MainWindow : Window
    {
        public ObservableCollection<RadButton> ButtonCollection1 { get; set; }
        public ObservableCollection<RadButton> ButtonCollection2 { get; set; }
        public RadButton SelectedButton1 { get; set; }
        public RadButton SelectedButton2 { get; set; }

        public MainWindow()
        {
            InitializeComponent();

            ButtonCollection1 = new ObservableCollection<RadButton>();
            ButtonCollection2 = new ObservableCollection<RadButton>();

            for (int i = 0; i < 10; i++)
            {
                RadButton button1 = new RadButton();
                button1.Name = "Button1_Item" + i;
                ButtonCollection1.Add(button1);

                RadButton button2 = new RadButton();
                button2.Name = "Button2_Item" + i;
                ButtonCollection2.Add(button2);
            }

            grid.DataContext = this;
        }
    }
}

[Yana]

Hello Chris,

It's not recommended to load UI elements in the view model. Please replace RadButton with a custom object in order to fix this issue. I've attached a simple example to demonstrate the approach.

Kind regards,
Yana
the Telerik team

[Chris]

Thanks Yana,
I was aware of non-ui-element works as in your sample.
But I wasn't quite sure why it doesn't work for ui-element types, such as Button?
There is a reason why I'm using a button.
I would like to know at least why it doens't support. It doesn't seem logical to me.  hmm..

Thanks.

-chris

[Yana]

Hello Chris,

I'm sorry for not explaining.

We follow the behavior of standard ComboBox.  If you replace RadComboBox with ComboBox in your example, you'll observe the same result.  I suggest to place the button in the ItemTemplate of the combobox. You can also set SelectionBoxTemplate as explained here.

Greetings,
Yana
the Telerik team

[Chris]

Thanks for trying to help
You are right, normal wpf behavior is the same but that still doesn't explain why it shouldn't work.
It looks more like a bug than a feature. ^^

Regards,

-chris