Changing a GridPanel cell value with getSelected().data.field_name does not work

[paul-2011]

Hey guys, I have a grid which after updating the data on the db I need to hard-code one of the cell's value which initial value was databound, I tried the following code but it is not doing anything, could you please point me to the right direction?
Thanks

Doesn't change the cell value;

Ext.getCmp("GridPanel1").getSelectionModel().getSelected().data.stat_name = "Hello"

[paul-2011]

I wanted to mention also that I have a Template Column which displays an image and when I call the following code it doesn't update the Template column, is there a way of doing it without reloading the store?

This code updates everything except for the Template Column plus I need to update a cell manually after this line which I still don't know how to do.

Ext.getCmp("frmDetails").getForm().updateRecord(Ext.getCmp("GridPanel1").getSelectionModel().getSelected());