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Answered Control is slow to respond.

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  • Brian@WTG avatar

    Posted on Mar 7, 2011 (permalink)

    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

    Reply

  • Posted on Mar 8, 2011 (permalink)

    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

    Reply

  • Posted on Mar 8, 2011 (permalink)

    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

    Reply

  • Brian@WTG avatar

    Posted on Mar 8, 2011 (permalink)

    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.

    Reply

  • Posted on Mar 8, 2011 (permalink)

    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

    Reply

  • Brian@WTG avatar

    Posted on Mar 8, 2011 (permalink)

    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

    Reply

  • Answer Svett Svett admin's avatar

    Posted on Mar 10, 2011 (permalink)

    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

    Registration for Q1 2011 What’s New Webinar Week is now open. Mark your calendar for the week starting March 21st and book your seat for a walk through all the exciting stuff we ship with the new release!

    Reply

  • Brian@WTG avatar

    Posted on Jun 15, 2011 (permalink)

    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.

    Reply

  • Svett Svett admin's avatar

    Posted on Jun 20, 2011 (permalink)

    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
    Q1’11 SP1 of RadControls for WinForms is available for download; also available is the Q2'11 Roadmap for Telerik Windows Forms controls.

    Reply

  • Martin avatar

    Posted on Sep 5, 2011 (permalink)

    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?

     

    Reply

  • Svett Svett admin's avatar

    Posted on Sep 8, 2011 (permalink)

    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

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