Problem with datagrid component colume resize at runtime

Hey I am using the datagrid component to edit data from external XML.

i am having a problem with fix the size of coulum at runtime.

i am using a code is
// xmlConnector is xml connector instance name[/color]


[color=Blue]// navdetails is datagrid instance name[/color]

[color=Red]navdetails.getColumnAt(0).width = 80;
navdetails.getColumnAt(1).width = 80[/color];

I am at a loss any help would be great…if code helps Ill post her up.