Ajax tab control's TabContainer_ActiveTabChanged event is fired on each postback

Question

I am using Ajax tab control, which includes grids in each tab. The grid have drop down list and button and I want to fire gridview's RowCommand event on button click of gridview Row. But the problem is whenever I click on the button, Tabcontainet_ActiveTabChanged event is fired and grid view is bind again before it fire the RowCommand event.

I can not understand why this event is fired automatically even though I am not firing it intentionally. How can I fire RowCommand event in such cases?? I tried both with update panel and without update panel.

Answer 1

That's very strange but TabContainer fires ActiveTabChanged event on each postback if active tab changed or if actual ActiveTabIndex property value equals to 0. I can't find out any reason for such behavior so use solution below on on your own risk. Actually there are two solutions available: the first one is to download AjaxControlToolkit sources, change TabContainer control LoadPostData method and use custom dll :

Actual method:

protected override bool LoadPostData(string postDataKey, NameValueCollection postCollection)
{
    int tabIndex = ActiveTabIndex;
    bool result = base.LoadPostData(postDataKey, postCollection);
    if (ActiveTabIndex == 0 || tabIndex != ActiveTabIndex)
    {
        return true;
    }
    return result;
}

Just remove ActiveTabIndex == 0 condition from the code above.

Or you can create your own class inherited from the TabContainer, override that method and use this class instead of the default:

namespace AjaxControlToolkit
{
    /// <summary>
    /// Summary description for MyTabContainer
    /// </summary>
    public class MyTabContainer : TabContainer
    {
        protected override bool LoadPostData(string postDataKey, System.Collections.Specialized.NameValueCollection postCollection)
        {
            int tabIndex = ActiveTabIndex;

            if (SupportsClientState)
            {
                string clientState = postCollection[ClientStateFieldID];
                if (!string.IsNullOrEmpty(clientState))
                {
                    LoadClientState(clientState);
                }
            }

            if (tabIndex != ActiveTabIndex)
            {
                return true;
            }
            return false;
        }
    }
}