I doubt that this is an issue with the WinForms controls but I'll ask anyway in case anyone has experienced this problem (and I haven't found any solution searching the web).  My project is MDI with seven child forms so far.  After a few months of development I finally experienced a problem when I select several of my menu options (launch several child forms).  It doesn't matter what the order I select the menu options; the third menu option, whichever option that happens to be, gets a System.NullReferenceException.

The code for each menu option is this pattern:

The error happens at objDULAudit.Show(); (in this code example).  

System.NullReferenceException was unhandled
  HResult=-2147467261
  Message=Object reference not set to an instance of an object.
  Source=System.Windows.Forms
  StackTrace:
       at System.Windows.Forms.NativeWindow.WindowClass.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
  InnerException: 

I stepped through every line of code (as the child form instantiates) trying to run into the problem but I have not been successful.

Any ideas?

Thank you,

Gary

the data has been bind to radgirdview ,how to set the rowspan at runtime ? because must use set DataSource method to render data ,so cann't render the gridview cell by cell.

In the screen capture below I have a RadGridView in a RadCollapsiblePanel. I need to hide the border for both the CollapsiblePanel and the PanelContainer. 

I tried the code below - which I found on another form post = but to no avail:

radCollapsiblePanel1.ControlsContainer.PanelContainer.BorderStyle = System.Windows.Forms.BorderStyle.None;                   radCollapsiblePanel1.ControlsContainer.PanelElement.Border.Visibility = ElementVisibility.Collapsed;

What am I doing wrong?

Thanks

Carl

Hello,

I am looking for a freelance GUI Designer familiar with Telerik UI for Winforms for an internal Project

best regards

Stefan

I have a completely new winforms project. The only thing I adjusted was to change the target framework from .NET6 to .NET7 in the projects properties.

Now, each time I minimize (or maximize) a RadForm and then "normalize" it again, it is getting larger (some pixels to the right and to the bottom). This does not happen on .NET6 but on .NET7 and .NET8.

There is also an issue within the VS designer: When I open the form again its size is also slightly different (e.g. set to "300; 300" changed to "318; 243"). It also does not matter if I change the forms AutoScale value to "None", "Font", "DPI" or "Inherit".  Furthermore, I have no strange scaling in MS Windows, it is set to 100 %.

What is the reason for this behaviour and what do I need to do to prevent it?

I would also like you to check if this occurs to other controls, as well.

Hi,

Is it possible to modify mp4 output settings to increase video quality?

Currently it seems to be fixed at around 4 mbps which results in poor quality for full hd.

Thanks

Arturo

Is there a way to detect when the user clicks on the column header to sort.

An event like SortStarted and SortFinished?

I'd like to capture that event to perform some special processing.

I have a list of people in a datatable that I bind to a RadCheckedDropDown list via a bindingsource. This control is sited on the first page of a tab control. It's a list that provides the app user with a definable selection of staff members for a report.
On initialization of the form, only one item is selected, but as a test I check all items in the dropdown then move to the 2nd page of the tab control. If I then return to the first tab, the checkeddropdown list has returned to displaying only the initial single checked item .

I placed a breakpoint in my code and the dataset hasn't changed, ie the "Include" field still remains set to false for all rows except that initial row. ie checking items in the list aren't being reflected in the dataset. See untitled2.png

Have I failed to do something ?

      // 
      // CmbStaffFilter
      // 
      this.CmbStaffFilter.CheckedMember = "Include";
      this.CmbStaffFilter.DataSource = this.bsStaffFilter;
      this.CmbStaffFilter.DisplayMember = "Fullname";
      this.CmbStaffFilter.ItemHeight = 32;
      this.CmbStaffFilter.Location = new System.Drawing.Point(29, 35);
      this.CmbStaffFilter.Name = "CmbStaffFilter";
      this.CmbStaffFilter.ShowCheckAllItems = true;
      this.CmbStaffFilter.Size = new System.Drawing.Size(444, 20);
      this.CmbStaffFilter.TabIndex = 121;
      this.CmbStaffFilter.ValueMember = "RecId";

      // 
      // bsStaffFilter
      // 
      this.bsStaffFilter.DataSource = typeof(pulse.move.datasources.dsFilterStaff.dtFilterStaffDataTable);

Hi,

I used to do custom cells by adding controls through "createChildElements" methods, but it was really slow when having multiple columns and row displayed.

So I tried to use graphics only and I did everything in "PaintContent" methods. This is way faster, very smooth, but I sometimes have an error (very randomly) on bounds object (of radshaped form) being lock by another thread.

I wanted to know if this workaround for painting cells approved or not?

If not what/where would you recommand to do this?

Thanks in advance!

Simon