Aspxgridview edit form Cascading DropDown

Question

In ASPxGridView I have GridViewDataComboBoxColumn where in EditForm is there. Both the text and value fields are string only. If i select the value from 1st drop down means it not gettting value in second dropdrop down it return null value where i dont know where should i changee the code.

I am not get any value from 1st combo box . I am not getting any error.

Kind Check my Code.

[C#]
 protected void grdMaterialsFlow_CellEditorInitialize(object sender, ASPxGridViewEditorEventArgs e)
        {
 if (e.Column.FieldName == "SKU")
                {
                    DataSet ds = new DataSet();
                    FacilityId = ((DevExpress.Web.ASPxCallbackPanel)this.Page.Master.FindControl("cmpMastePageCallBackPanel")).FindControl("TitleContent").FindControl("cmbFacility") as DevExpress.Web.ASPxComboBox;
                    string val = FacilityId == null ? String.Empty : FacilityId.SelectedItem == null ? String.Empty : Convert.ToString(FacilityId.SelectedItem.Value);
                    ds = DBMethod.SelectSKUname(FacilityId.SelectedItem.Value.ToString());
                     ASPxComboBox cmb = e.Editor as ASPxComboBox;
                    SMgmt.PropddsUserRole = ds;
                    cmb.DataSource = ds;
                    cmb.ValueField = "SKU";
                    //cmb.ValueType = typeof(int);
                    cmb.TextField = "SKU";
                    cmb.DataBindItems();
                }
 if (e.Column.FieldName == "UOM")
                {
                    var combo = (ASPxComboBox)e.Editor;
                    combo.Callback += new CallbackEventHandlerBase(cmbUOM_OnCallback);
                    var grid = e.Column.Grid;
                    if (!combo.IsCallback)
                    {
                        string SKU = "";
                        if (!grid.IsNewRowEditing)
                            SKU = (String)grid.GetRowValues(e.VisibleIndex, "SKU");
                        FillUOMCombo(combo, SKU);
                    }
                }
}
 protected void FillUOMCombo(ASPxComboBox cmb, String SKU)
        {
            FacilityId = ((DevExpress.Web.ASPxCallbackPanel)this.Page.Master.FindControl("cmpMastePageCallBackPanel")).FindControl("TitleContent").FindControl("cmbFacility") as DevExpress.Web.ASPxComboBox;
            string val = FacilityId == null ? String.Empty : FacilityId.SelectedItem == null ? String.Empty : Convert.ToString(FacilityId.SelectedItem.Value);
            DataSet ds = DBMethod.SelectUOMname((SKU), val);
            cmb.DataSource = ds;
            cmb.ValueField = "UOM";
            cmb.ValueType = typeof(string);
            cmb.TextField = "UOM";
            cmb.DataBindItems();
        }
        void cmbUOM_OnCallback(object source, CallbackEventArgsBase e)
        {     

            var UOM = -1;
            Int32.TryParse(e.Parameter, out UOM);
            FillUOMCombo(source as ASPxComboBox, UOM.ToString());

        }

Answer 1

void cmbUOM_OnCallback(object source, CallbackEventArgsBase e)
        {
            ASPxComboBox combo = (ASPxComboBox)source;
            FillUOMCombo(combo, e.Parameter);
        }

This method is used to get the Text in the Combo Box