How to build style for GroupHeaderRow when using GroupRenderMode="Flat"?

[Rob]

Hello,

I've recently discovered the GroupRenderMode property in the RadGridView ad would like to try it out to see if it improves any performance issues we have.  I was the original poster who logged this post but unfortunately by switching to "Flat" my styles have dissappeared.

What property do I use to apply a GroupHeaderRow style to a RadGridView?  Until now, I was setting the GroupRowStyle property but as you can see from my attached picture, the styles are not applied to the new GroupRenderMode.  I see the documentation mentions that I should be working with a  "GroupHeaderRow" but I can't seem to find the property (and I'm not able to create an object of that type in Blend)

[Dimitrina]

Hello,

I am not sure how have you defined the "GridViewGroupStyle1", but I guess that the element you have targeted is not the right one. Please note that when you use the Flat Mode, you should work with GroupHeaderRow, not GridViewGroupRow.

I hope this helps.

Kind regards,
Didie
the Telerik team

[Rob]

Hi again,

Here is the code I am attempting to use to try and create the default GroupHeaderRow style:

<UserControl
   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"
   x:Class="SilverlightApplication41.MainPage"
   Width="640" Height="480"
>
   <Grid x:Name="LayoutRoot" Background="White">
      <telerik:GroupHeaderRow />
   </Grid>
</UserControl>

If I run this project, I get the following error:

No matching constructor found on type 'Telerik.Windows.Controls.GridView.GroupHeaderRow'.
No parameterless constructor defined for this object.
   at System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck)
   at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache)
   at System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache)
   at System.Activator.CreateInstance(Type type, Boolean nonPublic)
   at MS.Internal.XamlManagedRuntimeRPInvokes.CreateInstance(XamlTypeToken inXamlType, XamlQualifiedObject& newObject)

[Yoan]

Hi Rob,

 Actually, you can set a style for the GroupHeaderRow only implicity. Note that if you want to style a particular GridView, you can define the style in the GridView's resources. Please check the following code snippet for a reference:

<telerik:RadGridView.Resources>
 <Style  TargetType="telerik:GroupHeaderRow">
  <Setter Property="Background" Value="Red"/>
 </Style>
</telerik:RadGridView.Resources>

I hope this helps.
  Regards,
Yoan
the Telerik team

[Rodney]

Hi,,

I tried using this:

<telerik:RadGridView.Resources>
  <Style  TargetType="telerik:GroupHeaderRow">
     <Setter Property="Background" Value="Red"/>
  </Style>
</telerik:RadGridView.Resources>

But nothing happens ?! It's still the way it was before ?! 

Why?

[Vlad]

Hi,

 Do you have GroupRenderMode="Flat" for your grid? 

Kind regards,
Vlad
the Telerik team

[Rodney]

Hi,

Thanks for the reply, but  yes I do !

Thanks

[Vlad]

Hello,

 You can check the attached example application for reference. 

Kind regards,
Vlad
the Telerik team

[Rodney]

Hi,

Thanks for you reply.

I was able to find the answer, in my grid I use: telerik:StyleManager.Theme="Windows7", and when I put this theme, the background or any other property I put to telerik:GroupHeaderRow doesn't work! IS there a reason for that ?!

Thanks

[Vlad]

Hello,

 By setting theme with the StyleManager you are actually using explicit styles and no implicit style will be applied. To achieve your goal you can use implicit styles.  

All the best,
Vlad
the Telerik team