Hi,
Well, basing on your description we can provide you with the following example.
Generally, the idea is: you should be able to populate the second DropDownField as you need within the GridPanel's Command listener.
Example
<%@ Page Language="C#" %>
<%@ Register Assembly="Ext.Net" Namespace="Ext.Net" TagPrefix="ext" %>
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
if (!X.IsAjaxRequest)
{
Store store = this.GridPanel1.GetStore();
store.DataSource = new object[]
{
new object[] { "test1", "test2", "test3" },
new object[] { "test4", "test5", "test6" },
new object[] { "test7", "test8", "test9" },
};
store.DataBind();
}
}
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Ext.NET Example</title>
</head>
<body>
<form runat="server">
<ext:ResourceManager runat="server" />
<ext:DropDownField ID="DropDownField1" runat="server" Width="350">
<Component>
<ext:GridPanel ID="GridPanel1" runat="server" AutoHeight="true">
<Store>
<ext:Store runat="server">
<Reader>
<ext:ArrayReader>
<Fields>
<ext:RecordField Name="test1" />
<ext:RecordField Name="test2" />
<ext:RecordField Name="test3" />
</Fields>
</ext:ArrayReader>
</Reader>
</ext:Store>
</Store>
<ColumnModel runat="server">
<Columns>
<ext:Column Header="Test1" DataIndex="test1" />
<ext:Column Header="Test2" DataIndex="test2" />
<ext:Column Header="Test3" DataIndex="test3" />
<ext:ImageCommandColumn Width="25">
<Commands>
<ext:ImageCommand CommandName="accept" Icon="Accept" />
</Commands>
</ext:ImageCommandColumn>
</Columns>
</ColumnModel>
<Listeners>
<Command Handler="if (command === 'accept') {
var data = Ext.encode(record.data);
this.dropDownField.setValue(data);
DropDownField2.setValue(data);
}" />
</Listeners>
</ext:GridPanel>
</Component>
</ext:DropDownField>
<ext:DropDownField ID="DropDownField2" runat="server" Width="350" />
</form>
</body>
</html>