Dropdown has long delay

[William]

If I click on the dropdown arrow the box has a long delay before it opens (1 to 2 seconds).  Before it opens the following runs in the Output Window.  It does not matter if it is on my main form or a child form or with one item or 100.  Once it runs ALL dropdowns work fine after that.

Thanks


'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\System.Workflow.ComponentModel\3.0.0.0__31bf3856ad364e35\System.Workflow.ComponentModel.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\System.Workflow.Activities\3.0.0.0__31bf3856ad364e35\System.Workflow.Activities.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\System.Workflow.Runtime\3.0.0.0__31bf3856ad364e35\System.Workflow.Runtime.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\Microsoft.Build.Utilities\2.0.0.0__b03f5f7f11d50a3a\Microsoft.Build.Utilities.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\Microsoft.Build.Framework\2.0.0.0__b03f5f7f11d50a3a\Microsoft.Build.Framework.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
'Biosketch_2.vshost.exe' (Managed): Loaded 'C:\WINDOWS\assembly\GAC_MSIL\System.Web.Services\2.0.0.0__b03f5f7f11d50a3a\System.Web.Services.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.

[Nikolay]

Hello William,

Thank you for contacting us.

I tested several scenarios, but I was not able to reproduce any performance issues regarding RadComboBox. Please make sure that you have followed the optimization suggestions mentioned in these Knowledge Base articles: Optimizing RadComboBox and RadListBox performance, Using UI Virtualization in RadComboBox and RadListBox.

As to the Output, the messages are normal since you run your project in Debug mode, but the assemblies referenced are in Release mode.

If you continue experiencing the issue, please open a new support ticket and send me a sample project which reproduces it. This will allow me to assist you further.

Regards,
Nikolay
the Telerik team

Check out Telerik Trainer, the state of the art learning tool for Telerik products.

[Marc]

I too was experiencing this same characteristic on my development laptop, running an external monitor.  Not only did the combo box experience an annoying delay in opening on the first time, but it also caused flicker in other controls on the same form.  I found DoubleBuffer code on the net and made sure each control on the form was double buffered.  This helped, but didn't solve the issue to satisfaction.

After testing our software on other machines I noticed the delay and flicker were not occurring on the other systems.  I then rechecked my laptop video card settings and monitor driver.  it turned out I never installed the proper monitor drivers for the external monitor, and after doing this the delay and flicker were gone entirely.

I hope this helps, and really love your controls.

[Nikolay]

Hello Marc,

Thank you for the feedback. I hope that it will help others who may have similar issues.

I am updating your Telerik points for bringing your resolution to our attention.

Regards,
Nikolay
the Telerik team

Check out Telerik Trainer , the state of the art learning tool for Telerik products.