Telerik RadComboBox ItemTemplate and MultipleSelectionBoxTemplate-CodePudding

how can i specify MultipleSelectionBoxTemplate which i can access properties of selected items

i have an employee class

public class Employee {
public string Firstname {get;set;}
public string Lastname {get;set;}
}

I am using Telerik radCombobox in my wpf application to display list of employee

            <telerik:RadComboBox x:Name="radComboBox"
                                 Width="200" 
                                 AllowMultipleSelection="True" 
                                 ItemsSource="{Binding Path=EmployeeList}"  
                                 >

                <telerik:RadComboBox.ItemTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Path=Lastname}" />
                    </DataTemplate>
                </telerik:RadComboBox.ItemTemplate>

this works fine for itemtemplate but when i select an item the display text in combobox show name of Employee class not the Lastname i tried

                <telerik:RadComboBox.MultipleSelectionBoxTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Path=Lastname}" />
                    </DataTemplate>
                </telerik:RadComboBox.MultipleSelectionBoxTemplate>

i get no result , the combobox displayvalue of selected item is always empty.

i tried another solution

                <telerik:RadComboBox.MultipleSelectionBoxTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Path=SelectedItems,Converter={StaticResource SelectionToCustomStringCoverter}}" />
                    </DataTemplate>
                </telerik:RadComboBox.MultipleSelectionBoxTemplate>

this neither work , the converter always execute at first selection

this is really crazy spending 4 hours to figure out a simple thing , so my question is how can i specify MultipleSelectionBoxTemplate which i can access properties of selected items .

CodePudding user response：

this neither work , the converter always execute at first selection

You need to bind to a property that is actually set when the selection changes, such as the Count property of the SelectedItems collection.

Try using a multi value converter and a MultiBinding:

<TextBlock>
    <TextBlock.Text>
        <MultiBinding Converter="{StaticResource SelectionToCustomStringCoverter}">
            <Binding Path="SelectedItems" RelativeSource="{RelativeSource AncestorType=telerik:RadComboBox}"/>
            <Binding Path="SelectedItems.Count" RelativeSource="{RelativeSource AncestorType=telerik:RadComboBox}"/>
        </MultiBinding>
    </TextBlock.Text>
</TextBlock>

You will then get the currently selected items from values[0] in the converter.