When GridView has a GridViewComboBoxColumn that is bound to a list of objects and that list changes a null reference error is thrown.  This error did not get throw in the previous release (2013 Q1), it just started happening in (2013 Q2, specifically 2013.2.612.40).

Here is a code example using a list of Authors and a list of books.  Basically the book object has a reference to the Author object.  When the author list changes the book grid will throw a null reference error.

Here is the stack trace of the error:

   at Telerik.WinControls.UI.GridViewComboBoxColumn.AddItem(Int32 i)
   at Telerik.WinControls.UI.GridViewComboBoxColumn.currencyManager_ListChanged(Object sender, ListChangedEventArgs e)
   at System.ComponentModel.ListChangedEventHandler.Invoke(Object sender, ListChangedEventArgs e)
   at System.Windows.Forms.CurrencyManager.OnListChanged(ListChangedEventArgs e)
   at System.Windows.Forms.CurrencyManager.List_ListChanged(Object sender, ListChangedEventArgs e)
   at System.ComponentModel.BindingList`1.OnListChanged(ListChangedEventArgs e)
   at System.ComponentModel.BindingList`1.Child_PropertyChanged(Object sender, PropertyChangedEventArgs e)
   at GridTest.Author.NotifyPropertyChanged(String info) in c:\Users\SESA124669\Documents\Visual Studio 2012\Projects\GridTest\GridTest\Form1.cs:line 69
   at GridTest.Author.set_Name(String value) in c:\Users\SESA124669\Documents\Visual Studio 2012\Projects\GridTest\GridTest\Form1.cs:line 97
   at GridTest.Form1.button1_Click(Object sender, EventArgs e) in c:\Users\SESA124669\Documents\Visual Studio 2012\Projects\GridTest\GridTest\Form1.cs:line 52
   at System.Windows.Forms.Control.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnClick(EventArgs e)
   at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ButtonBase.WndProc(Message& m)
   at System.Windows.Forms.Button.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
   at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
   at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.Run(Form mainForm)
   at GridTest.Program.Main() in c:\Users\SESA124669\Documents\Visual Studio 2012\Projects\GridTest\GridTest\Program.cs:line 19
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

Here is the code:

Hello Telerik support,

I am using Office2010 themes (black, blue and silver) wth RadDock. There seems to be a problem when one want to dock a window under another with these themes: instead of docking under, it docks overs as if over the tab icon instead of the down arrow. There seems to have no problem on Right, top and left arrows. With other themes, I did not see such issue.

Tell me if this is not clear (it is not easy to explain).

Regards.

Hi,
in my scenario I need to know target TileGroupElement of drag and drop operation.
I try to use PreviewDragOver event:
and

When I do "Drag Over" RadTileElement I get RadTileElement,  but when I do "Drag Over" TileGroupElement I get RadPanoramaElement.

How I can get TileGroupElement in both cases?

Thanks,
Marek

Hi
I would need to do something like that:
http://www.radgametools.com/images/telethreads_big.png
Is it possible with your C# controls?
I didn't find how I would do it looking at the demos.
It needs to support thousands of "box"

Thanks

Nicolas Babin

private void SizeModeClick(object sender, EventArgs e)

        {

            RadMenuButtonItem item = sender as RadMenuButtonItem;

            pictureBox1.SizeMode = (PictureBoxSizeMode)Convert.ToInt32(item.Tag);

            sbSizeMode.Text = item.Text;

        }

 

 

 

The above code from the step by step tutorial is throwing a NullReference Exception.  I bolded the line that has the error, VS2012 says it should have a "new", but when i do that it will not compile.


System.NullReferenceException was unhandled
  HResult=-2147467261
  Message=Object reference not set to an instance of an object.
  Source=Winformtutorial
  StackTrace:
       at Winformtutorial.RadForm1.SizeModeClick(Object sender, EventArgs e) in d:\visual studio 12\Projects\Winformtutorial\Winformtutorial\RadForm1.cs:line 43
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at Telerik.WinControls.RadControl.OnClick(EventArgs e)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
       at Telerik.WinControls.RadControl.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at Winformtutorial.Program.Main() in d:\visual studio 12\Projects\Winformtutorial\Winformtutorial\Program.cs:line 18
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException:

Hi,
I need to make a copy when you drag an item instead of moving.
How to do it in the easiest way?

Thanks,
Marek

I have a VS.net (VB.net) 2010 project that I built last year and haven't opened since.  I'm sure the version of the controls I had installed at that time was older than what I have now.  Now, when I try to open that project I get a VS error that forces close, which is preventing me from being able to work with my project.  The VS error references Telerik.WinControls.GridView and says essentially "File Not Found".  How can I update this project so that it will now just use the current version of the controls that I have installed?

Hey there,

I've been looking around for ages and just can't seem to find anything that resembles the problem I have (Or I'm not looking for the right things). This is also why the title is so vague. I just don't know what's going wrong exactly

I'm trying to build hierarchy in a grid. At first I tried to create one programmatically. That one ended up looking like the image attached. So, I thought, perhaps I ended up making an error, thus I tried creating the intended grid through the property builder. But that one too ended up looking like attached image.

The designer code is as followed:

Any ideas as to why this is happening? I use version 2013.1.321.40 of the telerik components

Thanks in advance,

Jasper

EDIT: Of course, I should state as to what's wrong of course...
I expected the columns of the second level to be
- ID
- Product-Reference
- Product-Naam

And the last column just 'not be there'

Hi,
I have a data source which is a BindingList<Project> where Project is a class containing a Parent and a Children properties (as well as other properties like Id, Name, Description etc). The Parent property is of type Project and the Children property is of type BindingList<Project>. Suppose i don't know in advance the depth of this hierarchy, how can i configure the GridView to display it right? I couldn't find any useful demo, are there any that concern my issue?

Thanks ahead,
Uri

---------------------------------------------------
I figured it out!
I've added a ParentId property to the Project class and added a self reference to the gridview's relations collection:
this.radGridView1.Relations.AddSelfReference(this.radGridView1.MasterTemplate, "Id", "ParentId");

Hello,

I can't seem to figure this error out.  When I add the code below to the code for my main form it will throw the exception "An error occurred creating the form. See Exception.InnerException for details.  The error is: Object reference not set to an instance of an object."

The form is to manage a series of applications I have been creating.  The grid view shows a list of banned users and allows for Editing of the records as well as showing them.  I have a few text boxes that act as a form so when a row is selected, data is shown there.

I know its this line because if I comment it out the form loads perfectly fine.