RadComboBox - DropDown

[Priya Iyer]

Hi,

I have 3 RadComboBox and in the code behind I'm assigning a collection to the Itemssource. When I click dropdown in the combobox it is showing the data but it seems like it's taking some time or kind of slow. Could you let me know why this is happening?

Thanks!
Priya

[Pana]

Hi Priya,

Is it virtualized? Try setting ItemsPanel on the combo like this:

<telerik:RadComboBox>
    <telerik:RadComboBox.ItemsSource>
        <local:Items />
    </telerik:RadComboBox.ItemsSource>
    <telerik:RadComboBox.ItemsPanel>
        <ItemsPanelTemplate>
            <VirtualizingStackPanel />
        </ItemsPanelTemplate>
    </telerik:RadComboBox.ItemsPanel>
</telerik:RadComboBox>

Does it work faster this way?

Greetings,
Panayot
the Telerik team

[Priya Iyer]

Hi Panayot !

Thanks for the immediate reply. I have tried setting ItemsPanel as you said. It seems better. But still it is kind of sluggish.

Here is my code

 

 

 

<StackPanel Grid.Row="0" Grid.Column="1" VerticalAlignment="Bottom" Margin="3">

 

<Border Background="#99243870" CornerRadius="3">  

 

 

<TextBlock Style="{StaticResource HeaderWhiteStyle}" Text="Market" /> 

 

</Border>  

 

 

<ti:RadComboBox x:Name="radcmbboxMarket" Style="{StaticResource OppRadComboHeaderStyle}" SelectedItem="" Margin="-2,0-2,0"> 

 

<ti:RadComboBox.ItemTemplate>  

 

 

<DataTemplate> 

 

<TextBlock Text="{Binding name}" />  

 

 

</DataTemplate> 

 

</ti:RadComboBox.ItemTemplate>  

 

 

<ti:RadComboBox.ItemsPanel> 

 

<ItemsPanelTemplate>  

 

 

<VirtualizingStackPanel/> 

 

</ItemsPanelTemplate> 

 

 

</ti:RadComboBox.ItemsPanel> 

 

</ti:RadComboBox>  

 

 

</StackPanel>

 

 

Thanks!
Priya

[Pana]

Hi Priya,

Can you define sluggish. Also how much items you generate for the items source of the combo and are you sure that the delay is in the combobox and not in somewhat other source?

Greetings,
Panayot
the Telerik team

[Priya Iyer]

Hi Panayot !

I assigned itemssource inside PageLoaded() method. I'm getting items from the database and It has around 20 items.
When I click dropdown it is moving down slowly. It is not showing the data quickly. It is kind of animated movement. But I didn't use any animation here.

Thanks!
Priya

[Pana]

Hello Priya,

The combobox animates its popup. You can try to change the animation selector set on the combo to stop the animation. You can set to null the animation:AnimationManager.AnimationSelector. I believe there are other properties that can be set on the AnimationManager.

Best wishes,
Panayot
the Telerik team