Control is slow to respond.

[Brian@WTG]

Hello,

I have a form with 3 "drop down" selectors that are used to filter a data grid. They have quite a few records in them. The first one has 1800, second has 4100 and the third has 12800.

I have tried quite a few drop down objects. The default .net combobox control, then the raddropdownlist. The data returned from the query is fast but the binding to the control is slow for the .net object. The raddropdownlist is extremely fast and I was going to use that except for two things. First, I can't seem to get the control to "text align=left" so when a value that's wider then the control is chosen your cursor goes off the object. Second it doesn't have multiple columns. After I read the "Auto Complete" doesn't work for the multicolumncombobox, I wasn't going to use it.

But then I went through the demo and the filtering functionality is good enough to simulate auto complete even if the user still has to choose a selection, they sacrifice the auto population for the multiple column view.

I've tried to use the multicolumncombobox for the 1800 record control and it is slow to respond. Even after it binds the data, changing selections or filters has some hiccups. The box is bound to an .xsd with three columns in it and only refreshes when the form loads. Is there something I can toggle to improve performance of the suggestion popup box?

Alternately, if there is a way to set the "text align=left" on the raddropdownlist control, the speed of that object is unmatched and I would rather use that.

Thank you

[Emanuel Varga]

Hello Brian,

With the RadDropDownList you can format the visual items displayed in the dropdown, please take a look in the Demos application, more precisely in the DropDown & List -> Item Formatting.

Please let me know if this is enough in this case.

Hope this helps, if you have any other questions or comments, please let me know,

Best Regards,
Emanuel Varga
Telerik WinForms MVP

[Emanuel Varga]

Hello again,

Or you could always create your own VisualListItem, i have a code library project on how to do this here.

Although I have illustrated this for the list control, you can just change the type of the control from the RadListControl to RadDropDownList and everything will work just fine.

Hope this helps, if you have any other questions or comments, please let me know,

Best Regards,
Emanuel Varga
Telerik WinForms MVP

[Brian@WTG]

Thank you for the quick response. I will start a new thread in the dropdownlist forum for that control.

So the speed of the multicolumncombobox cannot be adjusted? I thought about trying to limit the list of items returned from the .xsd (like top 100) but without re filling and then re binding the control each time the value of the current filterdescriptor changes, I can't think of how to provide access to the entire data set.

[Richard Slade]

Hello Brian,

Are you sure you are posting in the correct technology area? from the sounds of it, you are not using Winforms controls... if that's correct, please could you post in the correct forum which will ensure a response that is appropriate for your needs. My apologies if you did intend to publish in the Winforms forums

Regards
Richard

[Brian@WTG]

I was trying to use the "RadMultiColumnComboBox" in my vb.net application. Filter changes are extremely slow to respond. Instead of that control I am now using the "RadDropDownList" because it's faster, though the example provided here does have a custom item list (he combined text with an image and a calendar object, basically another image), I'm just going to use the .xsd to combine some fields for a display member as a second column and have the value member be the necessary column.

When the form loads with the MultiColumn ComboBox, if you hit the down arrow, or start to type, there is at least a 10 second hang of the application. As I said in the first post, my test control had an 1800 record, 3 column data set. The bind to the control to load the form was reasonably quick, but as soon as you started to type in the text box, the refresh for the "filtered" results in the drop down was painfully slow. Then, if you backspaced and changed your query, it would hang again to reset sometimes worse than the first time.

I've already removed it from the form I was working on, but I will try to use it again when less records are involved, as it looks really nice. I would use it on the current form if it's performance was better - which is my original question. Is there something I can do to speed up the refresh of filtered results from the combo box? I thought about trying to limit the returned number of rows, but that will unfortunately block out data unless you re fill and re bind the data set to include the filter..

Thank you

[Svett]

Hello Brian,

Presently, there is no way to improve the performance of RadMultiColumnComboBox when filtering is applied. There are some planned tweaks regarding this feature that we will make in one of the next major releases.

Greetings,
Svett
the Telerik team

[Brian@WTG]

I was back on this particular form again and took the time to rebuild a multicolumncombo box with the new release of controls, unfortunately it still has long binding delays when the filter descriptor changes.

[Svett]

Hello Brian,

We did not have time to do a performance optimization in RadMultiColumnComboBox due to some critical issues that we had to addressed in the latest releases. Nevertheless, the performance is always important for us and we will do our best to prioritize the task in our to do list. 

Greetings,
Svett
the Telerik team

[Martin]

I also use the multicolumn combo as a kind of selection list. The combo gets filled with all product item numbers (about 1,500) and their descriptions.

I do this by setting the data source:

    inpArtikelnummer.DataSource = Artikel.SelectAll()

This goes pretty fast. However the first open takes more than a minute!
I know there's a "Populate On Demand" function for the WebControls, and I'm wondering... Isn't there something similar for WinForms?

 

[Svett]

Hello Martin,

This issue could be observed when using a lot of rows and the AutoSizeDropDownToBestFit option is set to true. You have to set this property to false to work around the issue. Presently, RadMultiColumnComboBox does not support load on demand functionality. We will consider your suggestion as feature request. If many customers require it, we will increase its priority in our TO DO list. 

Should you have any other questions, do not hesitate to ask.

Best wishes,
Svett
the Telerik team

[Arun]

Dear Support,

Can you please let us know weather the above issue is been resolved on current version ?.

We are using multicombo in our all major screen, after the full data is loaded these multicolumn combos starts hanging. 

is there any solution to optimize it or can you please share you suggestion on this.

Thanks,
Arun

[Svett]

Hi Arun,

The issue is not addressed yet. You can check its status and vote for it in our public issue tracking system. If the published work around do not resolve the issue on your side, I would kindly ask you to provide me with a sample project which demonstrates your scenario?

Regards,
Svett
the Telerik team

[Pete]

Hi,

I am new to Telerik but I had this problem and resolved it by adding:-

RadMultiColumnComboBox1.MultiColumnComboBoxElement.DropDownAnimationEnabled = False

This has made my drop down of 50,000+ items very quick, I also manually created the columns as shown in

http://www.telerik.com/help/winforms/multicolumncombobox-databinding.html 

Not sure if this will work for anyone else but worth a try.

[Chris Wruck]

This worked for me also:-

RadMultiColumnComboBox1.MultiColumnComboBoxElement.DropDownAnimationEnabled = False

Developers at Telerik, since this is now a confirmed fix for large table binding, there is clearly a problem with the constructor for the RadMultiColumnComboBox where it literally hangs for serveral minutes when binding on large tables. Please investigate the cause of this problem, and examine why setting the DropDownAnimationEnabled property = False solves the problem.

[George]

Hello Chris,

Thank you for writing.

We prioritize issues according to user demand, hence if more users vote for the issue, higher its priority in our To-Do list will be.

If you want to use RadMultiColumnComboBox to display a lot of data, I can recommend to you to use the implementation from our KB article Performance Boots with Virtual RadMultiColumnComboBox - Quick Loading and Fast Filtering using Trie. This RadMultiColumnComboBox is optimized for cases which require the loading and filtering a lot of data.

I hope you will find this information helpful.

Regards,
George
Telerik

[Brad]

After upgrading a projects Telerik WinForms version from 2011 Q3 to 2013 Q3, I encountered this problem, where MultiColumn ComboBox Gridview Columns began pausing for seconds before displaying the list.

Setting DropDownAnimationEnabled = False returned the new version to the opening speed of the older version.

[George]

Hello Brad,

Thank you for replying.

You see performance impact since simply in the 2011 version of our controls the DropDownAnimationEnabled property has no effect, as per this bug report - http://feedback.telerik.com/Project/154/Feedback/Details/111155-fix-animationenabled-and-dropdownanimationenabled-properties-have-no-effect. We always suggest to stop the drop down animations when dealing with large amounts of data.

Let us know if you have further questions.

Regards,
George
Telerik