Hi, I am experiancing an issue with the rad gridView where the binding errors are making the performance impossibe to work with,  the errors I get are

ystem.Windows.Data Information: 21 : BindingExpression cannot retrieve value from null data item. This could happen when binding is detached or when binding to a Nullable type that has no value. BindingExpression:Path=SelectedPane.IsActive; DataItem='RadPaneGroup' (Name=''); target element is 'PaneHeader' (Name='HeaderElement'); target property is 'IsHighlighted' (type 'Boolean')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=SelectedPane.IsActive; DataItem='RadPaneGroup' (Name=''); target element is 'PaneHeader' (Name='HeaderElement'); target property is 'IsHighlighted' (type 'Boolean')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=; DataItem=null; target element is 'RadMenuItem' (Name=''); target property is 'CommandParameter' (type 'Object')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=; DataItem=null; target element is 'RadMenuItem' (Name=''); target property is 'CommandTarget' (type 'UIElement')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=IsFloatingOnly; DataItem=null; target element is 'RadMenuItem' (Name=''); target property is 'IsChecked' (type 'Boolean')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=; DataItem=null; target element is 'RadMenuItem' (Name=''); target property is 'CommandParameter' (type 'Object')
System.Windows.Data Information: 10 : Cannot retrieve value using the binding and no valid fallback value exists; using default instead. BindingExpression:Path=; DataItem=null; target element is 'RadMenuItem' (Name=''); target property is 'CommandTarget' (type 'UIElement')

I have checked that the DataContext is not null, and when using the WPF built in Listbox in place of the RadGridView, I do not get any issues. I have seen the same question asked on StackOverflow with no response

https://stackoverflow.com/questions/17842712/wpf-cannot-retrieve-value-using-the-binding-and-no-valid-fallback-value-exists

Part of my code looks like this :

<telerik:RadGridView x:Name="SummaryGrid" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"
                             CanUserDeleteRows="False"
                             CanUserFreezeColumns="False"
                             RowIndicatorVisibility="Collapsed"
                             CanUserResizeColumns="False"
                             AutoGenerateColumns="False"
                             CanUserSortGroups="False"
                             GroupRenderMode="Flat"
                             ShowGroupPanel="False"
                             EnableRowVirtualization="False"
                             ItemsSource="{Binding VerifiedItems, FallbackValue={x:Static constant:FallBackConstants.FallBackBaseConversionsList}}">
            <telerik:RadGridView.Columns>
                -->
        <!--column shown the path -->
        <!--
                <telerik:GridViewDataColumn Width="*"
           Header="Type"
           IsGroupable="False"
                                            DataMemberBinding="{Binding Type}"
           IsFilterable="True"
                                            IsReadOnly="True">
                    <telerik:GridViewDataColumn.CellTemplate>
                        <DataTemplate>
                            <StackPanel HorizontalAlignment="Stretch" ScrollViewer.HorizontalScrollBarVisibility="Auto" ScrollViewer.VerticalScrollBarVisibility="Hidden">
                                <TextBlock Text="{Binding Type, FallbackValue={x:Static constant:FallBackConstants.FallBackString}}" />
                            </StackPanel>
                        </DataTemplate>
                    </telerik:GridViewDataColumn.CellTemplate>
                </telerik:GridViewDataColumn>

Is there anything that I might be missing in terms of binding on the RadgridView?

Hello Telerik

In my applycation, I choose a pdf file, create preview image by using ThumbnailFactory, and show file in PdfViewer. But I receive exception as title because Telerik's framework cannot read pdf file with encryption algorithm 4. And PdfViewer  I google this bug and find nothing. So can you provide me some tip, trick to get over this bug. Thank you so much.

Hey community,
the row redorder sample doesn't work within a RadLayoutControl. It looks like as if the RadLayoutControl would intercept the DragEvent, so the  GiveFeedbackEventArgs is not called within the RowReorderBehavior.
Can you provide me asample or give me a hint please.

I've tried it with this sample:

http://docs.telerik.com/devtools/wpf/controls/dragdropmanager/how-to/howto-draganddrop-within-radgridview

Kind regards,
Lars

Hi,

I would trace in a RadTreeView the structure Groups/Items, wher Groups is first level and Items second one.

I thought that I could intercept "Item Added To Group event", can I do this in somehow?

Two cases I shuold keep:

• I drag and drop 2 or more objects into RadDiagram, add theme both and create a group for theme.
• I have already 2 or more objects into RadDiagram, user selects theme and clicks "Group Items" command.
  
  
  
  

Hi,

firstly thanks so much for the work you've done in providing the Pivotgrid. It has great functionality straight out of the box and our clients will love it!  

My query is about row and column averages. I basically want to be able to highlight specific cells that fall below a row or column average. I know how to use the CellTemplateSelector to change the colour but don't know how to actually find the row, column or overall average so that I have an average threshold to compare the cell value against. For example, take the following grid...

           Q1    Q2    Q3    Q4

Fred     2       6       7      9

Wilma  10     10      3     9

How would I work out that Fred's average is 6 (2+6+7+9 / 4) or that the overall average is 7 (2+6+7+9+10+10+3+9 / 8) so that I can highlight the cells falling below the average?

Thanks for any help here : )

Iain.

RadAutoCompleteBox -  If the user select the invalid record (means other than the item in the list), we need notify the user and reset to the empty value.

could you please help me to resolve the issue.

Hi,

Following the steps of the documentation I installed the theme of visual studio 2013:

http://docs.telerik.com/devtools/wpf/styling-and-appearance/styling-apperance-setting-a-theme-overview

The problem I have is that it works for me in all grids except one that I have filters (I do not know if it has anything to do with). 

As you can see in the picture 1.png works fine.

Do you think it may be happening? Thank you.

Regards,

Gerard.

I was planning to use Winform-Gantt View. but I heard that recurring task is not supported in Winform Gantt-View.
(http://www.telerik.com/forums/show-multiple-tasks-on-one-line-in-gantt-view)

Thus, I change my plan to apply WPF GanttView for my project.
I tried many things using Telerik WPF demo for applying our project.
but I have some problems to do it.  

1. Is it possible to show miliseconds timeline in a Gantt View?

 I can only show in the minimum timeline as a minute (day:hour:01) 
Is it possible  to show miliseconds? or in a second?

2.  In the recurrent task, is it possible to custom move? (not all just one task)

Thanks , Hyeon