ASPxGridView无法使用ReadOnly False编辑行

i'm currently working on an aspx website wherein I am using an ASPxGridView control. I am able to show up data on my GridView the way I want it to appear. However, my problem occurs when I click on the Edit button (provided by the control itself under a Command Column). After clicking the said button, the GridView would change the row to an editable one. However, I can't change the values inside the textboxes. Please note that I have already set the ReadOnly Property to false both on the GridView's smart tag and on the xml source itself.i'm currently working on an aspx website wherei