OnClientDropDownOpened

The OnClientDropDownOpened client-side event occurs immediately after the drop-down expands to show its child buttons.

The event handler receives two parameters:

1. The instance of the toolbar firing the event.

2. An eventArgs parameter containing the following methods:

• get_item returns a reference to the RadToolBarItem that was opened. In this case it is a drop-down.

• get_domEvent returns the browser's event object

You can use this event to respond to an action right after the drop-down has been expanded:

ASPNET

<script>
    function OnClientDropDownOpened(sender, args) {
        alert(args.get_item().get_buttons().get_count());
    }       
</script>

<telerik:RadToolBar RenderMode="Lightweight" ID="RadToolBar1" runat="server" Orientation="Horizontal" 
	OnClientDropDownOpened="OnClientDropDownOpened">
    <CollapseAnimation Duration="200" Type="OutQuint" />
    <Items>
        <telerik:RadToolBarButton Text="button1" runat="server">
        </telerik:RadToolBarButton>
        <telerik:RadToolBarDropDown Text="dropdown" runat="server">
            <Buttons>
                <telerik:RadToolBarButton Text="Button2" runat="server">
                </telerik:RadToolBarButton>
            </Buttons>
        </telerik:RadToolBarDropDown>
    </Items>
</telerik:RadToolBar>